Projected due date calculator

Calculate your due date: How to find your baby's due date

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First day of my last period

BabyCenter's Due Date Calculator

Use our pregnancy due date calculator by plugging in either the date of your last menstrual cycle or the date you know you conceived. The calculator will do the rest.

How is my due date calculated?

There are several ways your due date is determined. If you happen to know the day you conceived, you can count 38 weeks from that day to find your due date. (Human gestation takes about 38 weeks.)

But very few expectant moms know exactly when they conceived. Even if you only had sex once during your fertile period, you wouldn't conceive on that day unless you happen to be ovulating. Sperm can live for up to five days inside your fallopian tubes. So, it could be up to five days after you have sex that you release an egg (ovulate) and it gets fertilized by a waiting sperm. That's the day you conceive.

So, without knowing the day of conception, how does anyone determine a due date?

First day of your last period

The most common way to calculate your pregnancy due date is by counting 40 weeks from the first day of your last menstrual period (LMP). And that's how most healthcare providers do it.

If your menstrual cycle length is the average length (28-day cycle), your menstrual cycle probably started about two weeks before you conceived. This explains why pregnancies are said to last 40 weeks instead of 38 weeks.

This method doesn't take into account how long your menstrual cycle actually is or when you think you might have conceived. But generally speaking, women typically ovulate about two weeks after their menstrual cycle starts. And women are more likely to know when their last period started than the day they ovulated.

Conception date

If you do happen to know precisely when you conceived – say, if you were using an ovulation predictor kit or tracking your ovulation symptoms – you can calculate your pregnancy due date based on your conception date. Just choose that calculation method from the pulldown above and put in your date.

Note: Again, you don't necessarily conceive on the day you have sex.

IVF transfer date

If you conceived through IVF, you can calculate your due date using your IVF transfer date. If you had a Day 5 embryo transfer, count 261 days from your transfer date. If you had a Day 3 embryo transfer, count 263 days.

Can my due date change?

Your healthcare provider might revise your due date if your baby is measured during a first trimester ultrasound scan and found to be much bigger or smaller than expected for gestational age. This is more likely to happen if you have an irregular menstrual cycle length that makes it hard to pinpoint the date of conception.

Your healthcare provider will measure your baby during that ultrasound exam to figure out how far along your baby is and then provide you with a new due date.

What if I already know my due date?

If you already know your due date, you can use this calculator to see your pregnancy timeline. It will tell you when you'll hit various milestones, and when you may be due for prenatal tests and prenatal visits. You'll also find what your baby's sign and birthstone will probably be and which famous people were born on your due date.

How likely am I to give birth on my due date?

Of course, a due date calculation is always approximate, whether it's from our tool or from your doctor or midwife. Only 1 in 20 women delivers on their due date. You're just as likely to go into labor any day during the two weeks before or after.

Want more information about how the weeks, months, and trimesters of pregnancy are counted? See our pregnancy timing chart.

How soon can I take a pregnancy test?

With all this talk about pregnancy due dates, you may be wondering when you can take a pregnancy test. To ensure you get the most accurate reading, it's best to wait a few days after your missed period to take a pregnancy test.

At-home urine tests measure the amount of hCG (human Chorionic Gonadotropin) present in your body. If you take a pregnancy test before you miss your period, you may not get an accurate result, despite what some tests advertise.

If you're getting a blood test in your provider's office, you may get results sooner. These tests also measure the amount of hCG in your bloodstream, but they're more sensitive than at-home urine tests. Blood tests may be able to detect pregnancy six to eight days after ovulation.

Read more

• Your pregnancy, week by week
• Your first trimester pregnancy checklist
• Pregnancy Weight Gain Calculator
• Ovulation Calculator
• See all tools

Pregnancy due date calculator - Flo

The first day of your last period The day you conceived

Average cycle length

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• Please note that Flo Health does not collect, process, or store any of the data that you enter while using these Tools. All calculations are done exclusively in your browser. Flo Health does not have access to the results. All data will be permanently erased after leaving or closing the page.
   
• Our Due Date Calculator is based on a 28-day cycle (cycles can vary from 20 to 45 days), and your period and ovulation are considered to be the first 2 weeks of pregnancy. As this method is affected by the regularity of your menstrual cycle, the due date predictor is not 100% accurate.
   
• Remember that pregnancy due date calculators, birth date calculators, and pregnancy calculators can help you learn more about your estimated due date and pregnancy timeline, but they are not a replacement for medical advice. You should always notify your health care provider that you are pregnant. Sometimes an ultrasound will be needed to date your pregnancy.

You will meet your baby on

date

day

Gestational age is

weeks and day

Gestational age is the age of pregnancy and is counted from the first day of your LMP. So technically it includes two weeks during which you weren't pregnant yet.

Week 1

At 1 week pregnant, you’re actually not pregnant yet. As your pregnancy is calculated from the first day of your last menstruation, your baby does not yet exist, and your body is preparing for the ovulation during which you’ll get pregnant.

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Week 2

At 2 weeks pregnant, you’re technically not pregnant yet. Right now there is a lone egg and a whole bunch of anxious sperm eager to fertilize the egg. Your uterus and the entire body are preparing for a big day of ovulation - the stage when you'll get pregnant.

Read more

Week 3

Week 3 of pregnancy is the week when the implantation happens. Your body releases chorionic gonadotropin (hCG), which causes an increased production of estrogen and progesterone, and prevents new eggs in the ovaries from ripening. Very soon you'll start experiencing the first symptoms of pregnancy: missed period, nausea, breast changes.

Read more

Week 4

At 4 weeks pregnant, your baby is the size of a poppy seed.

At 4 weeks pregnant, your future baby has finally found his home for the next eight months. The blastocyst has arrived from a fallopian tube to your uterus. You can get a positive pregnancy test result at this stage.

Read more

Week 5

At 5 weeks pregnant, your baby is the size of a sesame seed.

By week 5, you should have missed your period, which is one of the most obvious sign you're expecting. Under the influence of hormonal changes, you can feel the first signs of pregnancy: breast swelling, fatigue, headache, and back pain.

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Week 6

At 6 weeks pregnant, your baby is the size of a lentil.

Starting from pregnancy week 6, you may experience morning sickness. This is the result of hormonal changes occurring in your body. Malaise, breast swelling, darkening of the nipple areola, and frequent urination can bother you, too. In case of bleeding, you should consult your doctor.

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Week 7

At 7 weeks pregnant, your baby is the size of a blueberry.

At 7 weeks pregnant, symptoms start kicking in and your uterus almost doubles in size. Be prepared for a possible increase in nausea, fatigue, heartburn, and other pregnancy symptoms. Morning sickness may give a lot of trouble. Try to find some ways to cope with it.

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Week 8

At 8 weeks pregnant, your baby is the size of a bean.

At 8 weeks pregnant, you need to plan your first visit to the gynecologist. The doctor will prescribe the necessary tests and examinations for the first trimester of pregnancy. You may feel the growing discomfort of morning sickness. Try to be patient; it usually lasts until the 14th week only.

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Week 9

At 9 weeks pregnant, your baby is the size of a cherry.

At 9 weeks pregnant, your baby is already about 0.6–0.7 in (16–18 mm) and weighs about 0.11 oz (3 g). The tail has disappeared; human features are becoming more distinct. The joints of his/her hands and legs can flex; the nipples and hair follicles are developing. Taste buds are beginning to form on the tongue, as well as primary tooth buds in the gums.

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Week 10

At 10 weeks pregnant, your baby is the size of a kumquat.

Week 10 of pregnancy is the time when almost all vital organs and tissues of your baby have formed. Now, they are beginning to function and grow rapidly. He or she can swallow amniotic fluid and move their arms and legs. The skin is getting covered with small hair and the fingers have tiny nails. Testes in boys already start to produce testosterone.

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Week 11

At 11 weeks pregnant, your baby is the size of a fig.

At 11 weeks pregnant, your baby has already reached 2 in (5 cm) in size. Now, his/her head is half the length of the body, but in the coming weeks, the body will grow enough to make up for it. The fetus skin is so thin and translucent that through it you can see an extensive network of vessels. Placental vessels are expanding to provide the fetus with necessary nutrients and oxygen.

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Week 12

At 12 weeks pregnant, your baby is the size of a plum.

At 12 weeks pregnant, your baby weighs about 0.49 oz (14 g). His/her vocal cords are forming, and kidneys are starting to produce urine, filling the bladder. Although you cannot feel it yet, you can see the baby during a sonogram screening (ultrasound).

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Week 13

At 13 weeks pregnant, your baby is the size of a pea pod.

Welcome to the last week of the first trimester! Most early pregnancy symptoms will soon be left behind. At 13 weeks pregnant, your baby is constantly growing. Now, he/she is more than 2. 8 in (7 cm) from the top of his/her head to the coccyx.

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Week 14

At 14 weeks pregnant, your baby is the size of a peach.

At 14 weeks pregnant, your baby is developing rapidly. In a while, you will be able to feel them moving and kicking. Your body starts actively gaining weight. This occurs due to an increase in blood and lymph volume.

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Week 15

At 15 weeks pregnant, your baby is the size of an apple.

At 15 weeks pregnant, your baby your baby is actively drawing in amniotic fluid through his/her nose. Very soon you'll start looking pregnant indeed as your uterus has risen from your pelvic region to your lower abdomen. Time to plan pregnancy shopping!

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Week 16

At 16 weeks pregnant, your baby is the size of an avocado.

You’re on week 16 of your pregnancy, and things are really starting to gear up! Your tiny baby is not so tiny anymore, and it most definitely looks like a human baby now. By week 16 of your pregnancy, you’re 4 months in. That means you’re nearly halfway there and only have 5 more months to go!

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Week 17

At 17 weeks pregnant, your baby is the size of a potato.

If you’ve been enjoying a relatively subtle pregnancy with very little belly to show for it, that’s probably over now! Your waist will gradually disappear as your uterus moves upwards and out of your pelvis.

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Week 18

At 18 weeks pregnant, your baby is the size of a bell pepper.

If you’ve been astonished by your baby’s rapid growth and weight gain over the last few weeks, by week 18 this will start to level off a little — but there’s still lots of big news in your little one’s early life! At this stage, he or she can yawn, stretch, and even make facial expressions like frowning. The baby’s sense of taste is developing, and taste buds can now distinguish between sweet and bitter.

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Week 19

At 19 weeks pregnant, your baby is the size of a mango.

At 19 weeks pregnant, your rounded belly is very noticeable. The first hair appears on the baby's head, and the brain areas responsible for the senses — tactile, gustatory, olfactory, visual and auditory — are developing rapidly.

Read more

Week 20

At 20 weeks pregnant, your baby is the size of a grapefruit.

Congratulations! You are halfway to meeting your baby. The baby's legs have almost straightened, so from now on, he/she will be measured from head to toe.

Read more

Week 21

At 21 weeks pregnant, your baby is the size of a banana.

As a 21 week pregnant woman, you have crossed the halfway line on your journey to becoming a mother. Your baby is getting bigger. You can now definitely feel her presence as she explores the real estate that you’ve prepared for her.

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Week 22

At 22 weeks pregnant, your baby is the size of a carrot.

If you are entering the 22nd week of your pregnancy, without doubts it is getting crowded in there! Your baby is growing and invading your space. And your uterus stretches to about 2 cm (0.8 in) above your belly button to fit your growing baby.

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Week 23

At 23 weeks pregnant, your baby is the size of a squash.

For many women, being 23 weeks pregnant is an exciting time because you may finally be showing your baby bump! Among other things, your baby’s eyes and lips are taking shape. They will begin to gain weight more weight which will eventually fill out their wrinkly skin.

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Week 24

At 24 weeks pregnant, your baby is the size of an eggplant.

At 24 weeks pregnant, your baby is almost a foot long. You could be experiencing a tingling sensation in your joints, which is known as carpal tunnel syndrome. It is a common condition during pregnancy which occurs due to fluid build-up in your joints which results in compression of the median nerve.

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Week 25

At 25 weeks pregnant, your baby is the size of a full ear of corn.

Once you reach week 25 of your pregnancy, you’ll be nearing the end of your second trimester. It can feel like times flies! At 25 weeks pregnant, you’re approximately 5 months and 2 weeks along. Your baby has been growing steadily and even though it’s still not ready, it won’t be long before it comes into the world.

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Week 26

At 26 weeks pregnant, your baby is the size of a beetroot.

You’re likely to put on between 16 and 22 pounds by now. At one point during this week, your baby will open his or her eyes for the first time. He or she is not yet able to see anything inside of the uterus but will blink closing and opening his or her eyes when falling asleep and waking up.

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Week 27

At 27 weeks pregnant, your baby is the size of a cauliflower.

The 27th week of the pregnancy marks the final two weeks of the second trimester. If your baby is more active at night you might suffer from insomnia and have trouble sleeping. Compensate for the lack of sleep time during the night by napping during the day more when the baby is sleeping.

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Week 28

At 28 weeks pregnant, your baby is the size of a coconut.

At 28 weeks you are now entering the third trimester of your pregnancy. At this stage, your baby is pretty well-developed. Her organs, tissues, and nerves continue to grow, but she already has all of the systems necessary for survival outside the uterus. Towards the end of the pregnancy, babies start to recognize familiar sounds and voices.

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Week 29

At 29 weeks pregnant, your baby is the size of a pomelo.

At 29 weeks pregnant, you're likely to develop varicose veins like 40 percent of expectant moms. It's also a good time to start doing a kick count. Let your doctor or midwife know if you notice that your baby is becoming less active.

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Week 30

At 30 weeks pregnant, your baby is the size of a head of cabbage.

At 30 weeks pregnant, you are likely to experience shortness of breath. Your baby is still up high near your rib and is waiting a bit – it is soon expected to drop down into your pelvis.

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Week 31

At 31 weeks pregnant, your baby is the size of a head of a zucchini.

At 31 weeks pregnant, your breasts can get leaky producing the first baby’s food – colostrum. This is one of the symptoms that your body is getting ready for the big day. You are likely to experience shortness of breath. This week your baby is going through major nerve and brain development.

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Week 32

At 32 weeks pregnant, your baby is the size of a head of lettuce.

At 32 weeks pregnant, your body may start flexing its muscles preparing for the big day. Your baby is also preparing for her debut mastering the skills she’ll need to thrive outside your womb: swallowing, breathing, sucking.

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Week 33

At 33 weeks pregnant, your baby is the size of a pineapple.

At 33 weeks pregnant, you may notice that your baby’s movements are affected by your daily routine. Your belly continues to grow and it’s getting even more troublesome to find a comfortable sitting or sleeping position.

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Week 34

At 34 weeks pregnant, your baby is the size of a butternut squash.

At 34 weeks pregnant, your breasts could start leaking small amounts of yellowish colostrum. Your baby is already the size of a school bag and weighs as a melon. If you’re worried about your safety at work, time to talk to your employer about maternity benefits.

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Week 35

At 35 weeks pregnant, your baby is the size of a honeydew melon.

At 35 weeks pregnant, you may know how your baby’s moving in your womb just by looking at your bump. It can you give you some discomfort and make you a bit breathless. At this point, many moms can’t wait for the baby to get here, while others are feeling a bit anxious about giving birth. Both feelings are completely normal!

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Week 36

At 36 weeks pregnant, your baby is the size of a papaya.

At 36 weeks pregnant, your baby is sleeping between 60 and 80% of the time. It has finally moved into your pelvic cavity, the pressure on your diaphragm is released, and lightening happens. Your baby can now open its eyes, suck its thumb, breathe, and recognize voices!

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Week 37

At 37 weeks pregnant, your baby is the size of a head of romaine lettuce.

Welcome to your 37th week of pregnancy, and congratulations! The baby moves further into the pelvis. It is considered to be ‘at-term’ and can actually arrive any day now. Make sure you are ready for the arrival of a new family member.

Read more

Week 38

At 38 weeks pregnant, your baby is the size of Swiss chard.

At 38 weeks pregnant, you can find yourself spending the whole life peeing. The pressure on your bladder is tremendous. Your baby is a fully functioning little human and your placenta is fully grown.

Read more

Week 39

At 39 weeks pregnant, your baby is the size of a small watermelon.

Welcome to the week 39 of pregnancy! Your baby is full term, meaning that it is fully developed and is only waiting for the right time to make an entrance into the world. Have you prepared everything that is needed to welcome your baby?

Read more

Week 40

At 40 weeks pregnant, your baby is the size of a mini watermelon.

At 40 weeks pregnant, you may feel disappointed that your due date has come and gone. Don’t panic and make the last preparations for a new human who’ll soon join the world.

Read more

Week 41

At 41 weeks pregnant, your baby is the size of a pumpkin.

At week 41 of pregnancy, you might be dying out of the desire to give birth and see your baby. But rest assured that plenty of moms-to-be go past their due date and everything turns out just fine.

Read more

Week 42

At 42 weeks pregnant, your baby is the size of a watermelon.

When a pregnancy lasts for 42 weeks or more it is referred to as a post-term pregnancy. While not many studies exist that prove why some women’s pregnancy lasts for 42 weeks, medical experts believe that factors such as hormones, genetics, and even obesity can be the cause.

Read more

Barbara Levy, MD

Former Vice President in Health Policy of the American College of Obstetricians and Gynecologists National Leadership Institute, CA, USA

If you’ve taken a pregnancy test and it appears to be positive, you might be wondering what happens next. That’s where our due date calculator or due date predictor comes in. 

By using some basic information about your last period and cycle length, our pregnancy calculator can help you work out your estimated due date (EDD — aka when you might meet your baby). This information is also useful if you’re thinking about the baby’s due date timings before you start trying to conceive.

Try using our EDD calculator now and then scroll down for more on how due dates (and pregnancy) are calculated, plus information on when you could have conceived and how far along you might be.

Note:

• If you’ve already had your first ultrasound scan, you can use our Due Date by Ultrasound Calculator instead.
• Or, if you have conceived through in vitro fertilization (IVF), you can use our IVF and FET Due Date Calculator.

One of the first questions you’ll probably have after discovering that you’re pregnant is “How pregnant am I?” Interestingly, there are two ways to measure the age of a baby during pregnancy — gestational age vs fetal age — but health care providers generally use gestational age only because it’s deemed more accurate.

More on those below, but when you know how far into your pregnancy you are, you can get a clearer idea of your expected date of delivery. This is another name for a due date, meaning your EDD is the approximate date when labor is expected to begin. As we’ll explain if you scroll down, this date is really just an estimate, so you can expect to go into labor anytime in the two weeks before and after your due date.

• How far along am I? Gestational age

To track pregnancy and calculate a due date, doctors use gestational age. Gestation is how long a person is pregnant in weeks, and gestational age is measured from the last menstrual period (LMP) — the first day of your last period — to the current date in weeks. 

In general, pregnancies last anywhere from 38 to 42 weeks (or around 280 days). If a baby is born before 37 weeks, they are considered premature.

• How far along am I? Fetal age

The other method of measurement is fetal age. While gestational age measures how far along a pregnancy is in weeks, fetal age is the actual age of the growing baby. To calculate this, you work out the amount of time from the date of conception (which is around two weeks later than your LMP in a 28-day cycle but varies depending on cycle length) to the current date in weeks. However, this is a far less common measurement for pregnancy because it’s often hard to pinpoint exactly when you ovulated (and therefore the moment of conception).

Lots of us assume that a pregnancy is exactly nine months long, but that’s not the case. To work out how to calculate pregnancy weeks, there’s a little more to it.

“The nine months of a pregnancy are actually 40 weeks,” Dr. Charlsie Celestine, Flo board member, obstetrician, and gynecologist (OB-GYN), explains. “The due date is 40 weeks from the first day of your last menstrual period. But some women can go beyond that to 41 weeks. ”

In fact, the first thing you’ll likely notice when you let your health care provider know you are pregnant is that pregnancy is calculated in weeks rather than months. And your baby’s estimated due date falls on the 40th week, when you’ll actually be around 10 months pregnant. 

That’s to account for the fact that pregnancy is measured according to gestational age, not fetal age. So that means you count pregnancy from your LMP, not the date you conceived, adding an extra two weeks even though you weren’t technically pregnant then. Also, this method recognizes that not all months have the same number of days, so you’ll likely still be pregnant at nine months. 

You might also see figures like 13/5 or 13+5 in your doctor notes. Pregnancy is counted in complete weeks, so 13/5, 13+5, or a variation of this would mean you’re 13 weeks and 5 days pregnant. Learn more about how you count pregnancy weeks here.

Your health care provider will usually calculate your due date based on one or a combination of the following methods, so let’s find out more about how they work.

As we now know, the most commonly used method to calculate due date is to count “40 weeks from the first day of your LMP,” Dr. Celestine says, adding that this is usually done at your first appointment. 

This method is also known as Naegele’s rule. “You calculate [EDD] using the first day of the last menstrual period [adding exactly one year to it], add seven days to that, and then subtract three months,” she explains.

It’s worth noting that this rule considers a regular menstrual cycle to be 28 days long, but it’s totally normal for a person’s cycle to vary from anywhere between 21 and 45 days. If your cycle lasts longer, the estimated due date will likely be later. If you have a shorter cycle, your due date may be earlier.

“More commonly, I use a pregnancy wheel using the first day of the menses [period],” says Dr. Celestine, explaining how she tends to work out the due date in her patients. 

A pregnancy wheel or gestation calculator is a simple calendar that works out your EDD or baby’s birth date based on different inputs, such as your LMP. OB-GYNs can also use a pregnancy wheel as a pregnancy timeline calculator to work out when you’ll have certain scans and screenings, along with your trimester dates.

As you’ve seen above, there are numerous ways to calculate an estimated due date — most involving the date your last period started. But an ultrasound scan in the first trimester is used to check that the dating based on the last menstrual period is correct. This is especially important if your period doesn’t always arrive at the same time each month. 

“The LMP is compared to an ultrasound because some women have irregular cycles [and some can’t remember when their last period happened], so their LMP is not the most accurate,” Dr. Celestine explains.

“On ultrasound, I would measure the length of the fetus, called the ‘crown–rump length,’ in the first trimester to get the gestational age or due date. I then compare that date to the result I would get from just using the LMP.

“If the two dates are within five days of each other, and the pregnancy is less than nine weeks along, then we use the due date calculated by the period, not the ultrasound. But for a greater-than-five-day difference, we use the ultrasound.”

Already had your first ultrasound scan? Then you can use our Due Date by Ultrasound Calculator.

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While most OB-GYNs use a combination of Naegele’s rule and the pregnancy wheel to determine EDD — and then use an ultrasound to confirm it — there are some other theories and methods about how to calculate due date. However, it’s worth noting that none of the following are currently used by health care providers to work out the due date, as there’s a lack of scientific evidence behind them. The theories are as follows:

One theory on how to calculate due date, also using LMP, is the Mittendorf-Williams rule. This is based on an old study from 1990, and there haven’t been any more recent studies to suggest it’s accurate, which is why health care professionals don’t commonly use it to predict EDD.

This rule is based on a decades-old study that showed that first pregnancies tend to be slightly longer (an average of 288 days from LMP), and for subsequent pregnancies, the delivery date is an average of 283 days from LMP. So …

• First, determine the first day of your last menstrual period.
• Next, count back three calendar months from that date. 
• Lastly, add 15 days to that date if it’s your first pregnancy or 10 days if it’s not your first pregnancy.

Parikh’s rule is another theory that lacks scientific evidence to back it up, so medical practitioners don’t commonly use it to calculate due date either. The idea goes, however, that it can help predict due date in those who have irregular cycles. So, how does it work? 

Loosely designed around Naegele’s rule, the expected date of delivery in Parikh’s rule is calculated by adding nine months to the date of your last menstrual period, subtracting 21 days, and then adding the duration of previous cycles. In short, use this formula: 

• LMP + 280 days – 21 days + the average length of previous cycles

Wood’s method considers the individual length of the menstrual cycle, as well as the number of pregnancies a person has experienced. However, there is also minimal research on this and its effectiveness. To work it out …

• First, you calculate your expected due date. Do this using the following formulas.
  - For first pregnancies: LMP + 12 months – (2 months and 14 days) = EDD
  - For subsequent pregnancies: LMP + 12 months – (2 months and 18 days) = EDD
   
• Then, you use the expected due date in the equations below.
  - For cycles longer than 28 days: EDD + (actual length of cycle – 28 days) = EDD
  - For cycles shorter than 28 days: EDD – (28 days – actual length of cycle) = EDD

If your cycle runs like clockwork, and you were having sex to get pregnant at a specific time, then you might have an inkling that conception happened on a certain date. But Dr. Celestine says that the conception date “isn’t used medically to calculate due date” because it’s often not accurate. 

That makes sense because we know sperm can live in the female body for up to five days, an egg can still be fertilized for up to 24 hours after its release from the ovary, and ovulation doesn’t always happen on the same day each month (you can find out when you’re likely to be ovulating each month using our online ovulation calculator). That means you can still get pregnant several days after you’ve had unprotected sex.

If you’ve had IVF, then your baby’s due date is calculated slightly differently, depending on:

• Whether you had a fresh or frozen embryo transfer
• If you had a frozen transfer, the age of the embryo when it was frozen. For example, if it was frozen on day three, then you will be two weeks and three days pregnant on the date of transfer. For embryos frozen on day five, it’s two weeks and five days pregnant on the date of transfer. Your clinic will be able to explain more.

The good news is that IVF due dates are generally more accurate because you’ll know exactly when you had your embryo transfer or medically conceived, although no due date is 100% accurate. Use our IVF Due Date Calculator to work out when you could be due.

There’s a lot that centers around it, so you’re probably wondering how likely it is that you’ll give birth on your due date. “The accuracy of the due date depends on how early in the pregnancy it was calculated and how predictable your menstrual cycle is,” Dr. Celestine explains.

“The earlier you see an OB-GYN to establish care for the pregnancy, the better, because the due date [from an ultrasound scan] is more accurate early in pregnancy compared to later. It’s rare for a baby to be born exactly on their due date [only around 4% of babies are]. Usually, delivery happens within a week before or after. But there are many babies also born prematurely, [along with] medical reasons why you might need to be induced for labor early, so it really depends on the individual.”

As Dr. Celestine explains, it’s hard to predict the exact day you got pregnant (unless you’ve successfully conceived after fertility treatment).

“It’s all an estimate because it depends on the day you ovulated,” she says. “If you know your cycle length and it’s always the same, then usually midway through your cycle prior to pregnancy is when conception occurred. ”

Lots of people will calculate their due date as one of the first things they do after finding out they’re pregnant. And that’s useful for having a rough idea of when your baby will arrive, but it’s worth noting that this should be confirmed by your health care provider. They will use information about your last menstrual period, plus your first ultrasound, to work out your EDD, and once this has been calculated, it’s rare for your due date to change.

It’s so unusual for the due date to change after your first ultrasound scan because knowing the gestational age holds a lot of importance in monitoring the health of a pregnancy. “There are certain tests that need to be performed at certain gestational ages during a pregnancy,” Dr. Celestine explains. “Knowing how far along you are is also important for following the growth of the baby, when we can expect to deliver, and much, much more.”

Some people like to be organized, and there’s nothing wrong with that. But it can be quite tricky to plan a due date because there are so many factors at play with conception that you (and your partner) don’t have control over.

Nobody ever knows for certain when they will conceive. Even if you pinpoint your fertile window and have plenty of unprotected sex during that time, you still won’t know for certain whether or not that will be the month you get pregnant. That’s because so much of it is up to chance. For context, 45% of young couples (under 35) will conceive after three cycles, and 65% will get pregnant after six cycles. So while you might want to plan to have a baby in a certain month, all you can really do is try.

And even if you do manage to conceive at a time that gives you your ideal due date, remember that your EDD is just an estimate. Babies come on their own schedule. While the “average” pregnancy lasts 40 weeks from the day of the last menstrual period, it is normal for babies to come anywhere from 37 to 42 weeks, so it’s best not to focus too much on a specific due date.  

Whether you’re currently pregnant or trying to work out when you’d be due if you got pregnant today, Flo can help. Use our Trying to Conceive mode to optimize your chances of getting pregnant by tracking your periods, which can help to identify your most fertile days. Alternatively, switch to Pregnancy Mode to get week-by-week updates for both your body and your baby.

Try some of Flo's other online tools, including our hCG calculator, our pregnancy test calculator, and our period calculator.

References

“Extremely Preterm Birth.” The American College of Obstetricians and Gynecologists, www.acog.org/womens-health/faqs/extremely-preterm-birth. Accessed 30 Aug. 2022.

“Heavy and Abnormal Periods.” The American College of Obstetricians and Gynecologists, www.acog.org/womens-health/faqs/heavy-and-abnormal-periods. Accessed 30 Aug. 2022.

“How Long Does Pregnancy Last?” The American College of Obstetricians and Gynecologists, www.acog.org/womens-health/experts-and-stories/ask-acog/how-long-does-pregnancy-last. Accessed 13 July 2022. 

Jukic, A. M., et al. “Length of Human Pregnancy and Contributors to Its Natural Variation.” Human Reproduction, vol. 28, no. 10, Oct. 2013, pp. 2848–55.

Khedri, Parichehr, et al. “Comparison of the First Trimester Ultrasound and Parikh’s Formula in Determining the Expected Date of Delivery: A Prospective Study.” BMC Pregnancy and Childbirth, vol. 21, 30. Apr. 2021, jbrms.medilam.ac.ir/article-1-152-en.pdf. 

Mittendorf, R., et al. “Predictors of Human Gestational Length.” American Journal of Obstetrics and Gynecology, vol. 168, no. 2, Feb. 1993, pp. 480–84.

Morgan, John A., and Danielle B. Cooper. “Pregnancy Dating.” StatPearls, StatPearls Publishing, 2021.

“Screening Tests in Pregnancy.” NHS, www.nhs.uk/pregnancy/your-pregnancy-care/screening-tests/. Accessed 13 July 2022. 

How to calculate the date of birth, determining the date of birth by the date of conception.

Immediately after a woman learns about her situation, it becomes necessary to find out the time when the child will be born. The date of birth can be calculated in various ways, both with the use of special equipment and through mathematical operations. Let's consider each of the methods in detail, pay attention to the more relevant ones.

How can I find out the due date?

To begin with, make sure that the delay that has arisen is a consequence of gestation. To this end, the test is repeated. 2 or more positive results 100% indicate an imminent addition to the family. An exception is violations when the fetal egg does not reach the uterine cavity. In this case, the death of the embryo is observed at the beginning. This requires cleaning the uterine cavity in a medical facility.

An expectant mother can calculate the gestational age and date of birth in several ways. To use them, it is necessary to know at least 1 of the following parameters:

• day of cyclic discharges;
• the number when the germ cells merged;
• time of ovulation;
• stir time.

Before calculating the birth number of a child, remember that the duration of the gestational period is normally taken as 38 weeks. In days, this is 266. In view of the fact that in most cases it is problematic to name the exact day of the “meeting” of germ cells, the date of birth is counted from menstrual flow. In such a situation, the duration of the entire period is 280 calendar days.

Determination of gestational age and due date

The choice of methods depends entirely on the details available. Each is extremely simple, so in practice every pregnant woman will apply them on her own. You can determine the date of birth by:

• the day of fertilization;
• menses;
• using ultrasound;
• to the number of observed movement.

Estimated date of delivery

Due to the lack of detailed knowledge, obstetricians often rely on the day of menstruation. So it turns out the preliminary date of birth. The term means that the day set as a result does not always coincide with reality. There are many reasons for this. The most common is the unequal length of a woman's menstrual cycle.

How to correctly calculate the due date?

First, the expectant mother should try to remember at least 1 of the required parameters mentioned above. The most accurate of the existing methods used to calculate the date of birth is ultrasound. It takes into account the rate of development of the embryo, allowing you to know with an accuracy of 1-3 days the current time of gestation. The date of the upcoming birth is so predicted only in the conditions of a medical institution. The procedure is carried out at 12-14 weeks.

Date of birth according to the date of conception

Thanks to observations, it turned out that the time during which the fetus is fully formed is 266 days. The starting point is set from how the formation of the zygote occurred. Given this rule, in order to calculate the term of childbirth by the date of conception, the duration of gestation is added to the known day. For simplicity, they often count by weeks, adding 38.

It is worth noting that it is problematic to calculate the date of birth in this way. Not all girls take daily measurements of basal temperature, keep a schedule. Immediately at this time, there is a capture by the spermatozoon of a mature egg that has left the follicle. In addition, the process itself is strongly influenced by external factors (stress, overstrain, physical activity), which causes its displacement. As a result, cell fusion occurs earlier or later than the predicted day.

Date of delivery by the date of the last menstruation

A common algorithm applicable not only to ladies in position, but also to gynecologists. To understand how to calculate the day of birth according to the last menstruation, you need to accurately recall the former menstruation. The fair sex, who monitor their health, does not have problems with this, so the date of birth is considered quickly. Difficulties can only be in a situation where the girl had an irregular menstrual cycle.

In order to calculate the date of birth from the last menstruation, use the Naegele formula. According to her, 3 months are subtracted from the first day of the observed menstruation, after which 7 days are added. The same result if you add 40 weeks. Due to the simplicity, ease of action, the method is most widely used, even considering the inaccuracy and low objectivity.

Date of birth by first movement

An additional option used to specify the due date. Allows you to confirm or refute the received data. Speaking about how to calculate childbirth by the first movement, obstetricians point to the dependence of the parameter on the number of previous gestations. For mothers expecting their first child, "tickling" occurs at 20 weeks. Those carrying a second baby notice this at 18.

Date of birth by ovulation

Calculate the time of birth of a child in this way can be calculated by those pregnant women who have kept a chart of basal temperature for a long time. Normally, the release of the germ cell is observed directly in the middle of the cycle. So, if its length is 26-28 days, then it is fixed at 13-14. To calculate childbirth by ovulation, 280 days are added to the existing day. The result is the approximate time of birth of the crumbs.

The method is not widely used for several reasons. Among them:

• not all girls know the days when an egg is released in the body;
• the procedure for their identification requires long-term observations, the acquisition of special tests.

In addition, the fusion of the spermatozoon and the egg occurs later than the release of the female sex gamete. It is due to the fact that for 48 hours, it retains its viability and can be fertilized. As a result, the birth of a new life cannot be known with high accuracy in this way. Obstetricians and gynecologists do not use it, even when the approximate time of origin in the body of such a complex process is known.

Online pension calculator calculates retirement age seniority for a pension. The final result will depend on the input you enter.

How to use the calculator

Instructions for using the new retirement calculator

1. Select gender and date of birth.
2. If you have a length of service that gives you the right to early retirement, then indicate it.
3. Click "CALCULATE". From the result you will find out: the date of retirement, how old you will be at this moment and how many years you still need to work before retirement.

About the retirement calculator

The purpose of the pension calculator is to help in calculating the formation of the pension period and the timing of retirement.

IMPORTANT! Our pension calculator has already been created taking into account the amendments made to the legislation of the Russian Federation, known as the Pension Reform, adopted by the State Duma of the Russian Federation and signed by the President on 10/03/2018.

Scope

Using the calculator, you can easily calculate the retirement date of any citizen. The calculator is especially important for people of pre-retirement age, since it is their retirement that will be regulated according to a special grid, based on the phased implementation of the provisions of the pension reform.

Various types of pension calculators are very common on the Internet, which is explained by the increased interest of citizens in the issues of calculating pensions. However, it should be remembered that there is no calculator , which could at least approximately reliably calculate the amount of your future pension payments. This is due to many reasons, the main of which is the extreme opacity of the pension savings calculation system practiced by the PFR.

Legislatively, the factors that directly affect the amount of insurance pension accrual include:

1. Salary of a future pensioner or declared self-employment income.
2. Length of service.
3. Socially significant periods of life, which include military service, maternity leave, parental leave.
4. The method of pension provision chosen by the future pensioner in the system of compulsory pension insurance.
5. Continuing employment after retirement age.

All these factors are constantly changing, and a radical break in the pension system of the Russian Federation brings changes almost daily.

Therefore, the only reliable calculations of the calculator can be provided only in part:

1. forecast year for retirement;
2. retirement age;
3. minimum length of service required for retirement.

Retirement age

The pension reform, along with raising the age limit, also provided for the phased retirement of those who, at the time of the introduction of the reform, had either already reached the required age or approached it. In accordance with the stages of the reform, the age increase provided for by the reform will take place according to the formula 1/1, that is, once a year for a year. The total period of introduction of reform conditions will take 9years.

Men from 1959 and women from 1963 are subject to pension innovations. Those born earlier than these years are not threatened by the reform, even if they continue to work. This is due to the fact that the reform does not provide for retrospectiveness, that is, retrospective effect.

Extremely simplified, the stages are reflected in the following schemes for men and women.

Men:

Women:

That is, starting in 2028 (of course, if everything goes as the Government and the State Duma suggest), the introductory period will end and Russians will begin to go on a well-deserved rest immediately after they reach the appropriate age.

Seniority for pension

The pension legislation provides for the inclusion in the pension experience not only of the time directly employed by labor activity, but also of the periods attributable to the so-called "socially significant". The latter include the years of a citizen's life, busy with affairs that are important for society and the state as a whole - service in the Armed Forces, the birth and upbringing of children, caring for a sick or elderly relative, etc.

The pension reform provides for an increase in the required minimum service as the stages of raising the retirement age are introduced. In accordance with the stages given in the tables above, the stages of increasing the minimum length of service required for retirement are also distributed. The decision of Russian legislators to establish equal requirements for women's and men's seniority seems somewhat wrong, and perhaps some modifications will be introduced in this part over time, however, at the moment, the stages of increasing the size of the experience are as follows:

Point system

The calculation of pension points is a very time-consuming process, the algorithms of which, although given in pension legislation, are actually known only to employees of pension funds.

It is also difficult to calculate the number of points because the required minimum points increase by 2.4 points every year. If in 2015 about 7 points were enough for retirement, then by 2025 potential pensioners will have to have at least 30 points.

Moreover, different types of work and significant periods in life give a different number of points, regulated by various legislative acts. Whether this was done intentionally or by accident, the fact remains that an accurate independent calculation is impossible.

Currently, at the level of the State Duma and the Government of the Russian Federation, there is an intense discussion of abandoning the points system, and it should be thought that after raising the retirement age, the procedure for accumulating points will be abandoned. Therefore, no matter how many forecasts calculators give, no matter how many calculation tables are given, most likely they will turn out to be unnecessary.

Exceptions

As with any rule, there are exceptions to pension changes, that is, those cases in which innovations will not be applied, although some look completely illogical. Exceptions include:

1. Funded pensions. Pre-pensioners will have the right to use the accumulated funds from the moment they reach retirement age under the old legislation, that is, from 55 and 60 years old, depending on gender. In this case, there is a slight limitation. The right to use savings can only arise if there is a minimum experience of 15 years and a score of at least 30.
2. Insurance pensions for beneficiaries who retained the right to early retirement . In addition to those employed in hazardous industries (lists 1, 2), they will also include drivers of heavy trucks in mines and mines, field geologists, lumberjacks, women asphalt pavers and crane operators, railway machinists (including the metro) who directly transported passengers , port dockers, public transport drivers, fishermen, miners, civil aviation workers directly involved in providing flights, operational employees of the Ministry of Emergency Situations, employees of corrective labor colonies.
3. State pensions . The changes will not affect the persons who liquidated the Chernobyl accident, the persons affected as a result of the Chernobyl accident, as well as their close relatives - family members.
4. Civil servants' pensions. This category of future retirees will have its own phased schedule from 2018, which will increase the retirement age by six months each year until the thresholds are reached.

Medical and teaching staff

Significant changes await workers in the medical and teaching sectors. If before the amendments to the legislation these categories of workers could retire upon reaching a special teaching or medical experience, then, starting from 2019, they will be able to use their right to early retirement only 5 years after they accumulate all the same 25-30 years of professional experience.

A phased regime for raising the retirement age has also been introduced for physicians and teachers in accordance with the table below:

Thus, starting from 2023, all doctors and teachers will be able to declare their desire to go on vacation only 5 years after working for this experience.

Northerners

Citizens who worked in the conditions of the Far North or equivalent to them also received their "five-year plan". Now their retirement age will increase by this figure and will be 55 and 60 years (depending on gender).

"Estaging" of the retirement age, in order to avoid shock, is also provided for northerners. In general terms, it corresponds to the stages for all other citizens, with the exception that northerners will still be retiring on preferential terms.

Northern men:

Northern women:

Mothers of many children

Pension benefits under the new legislation will be provided to women belonging to the category of large families, regardless of the status of children - relatives or adopted. Each child, starting from the third, will give his mother 1 year of grace.

Three children will give the mother 3 grace years, that is, the opportunity to retire at 57 if there are no other benefits.

Four children will give the mother 4 grace years, which will allow her to retire four years earlier than citizens who do not have benefits.

Retirement for women who have given birth or adopted five or more children will not undergo any changes and will take place at the age of 50 years.

Schedule 1 experience for men and women

If you have such length of service, you can retire early, according to the table below.

List 2 experience for men and women

If you have such length of service, you can also retire early, according to the table below.

Experience in the Far North for men and women

If you have a "northern" seniority, you can retire early, according to the table below.

For teachers, doctors, artists and residents of the Far North

A gradual increase in the retirement age is made according to the table below.

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