Calculate baby delivery date

Pregnancy Due Date Calculator | BabyCenter

Calculation method

When did your last period start?

mm-dd-yyyy

Cycle length

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 her 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

BabyCenter Staff

Content that appears under this byline was created by members of the BabyCenter Editorial team.

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When does a baby have a heartbeat? When you can hear or see the heartbeat.

Photo credit: iStock / someone25

You may be able to see the beating of cells in the heart tube for the first time when you're about 6 weeks pregnant if you have an early ultrasound exam.

If you don't have a first-trimester ultrasound, you'll probably first hear your baby's heart with a handheld Doppler at a regular prenatal visit.

Your caregiver may be able to find cardiac activity with a handheld Doppler as early as 10 weeks, but the timing depends on a number of factors, including the position of your uterus, your belly shape, and how full (or empty) your bladder is.

When does a baby have a heartbeat?

At 5 to 6 weeks of pregnancy, there's a flickering of cells within the embryo's torso. This flickering is the developing heart tube.

At this point, the heart isn't the four-chambered organ we're familiar with. It's a tube-shaped structure that has a lot of developing to do. The heart tube bends and twists to eventually form the heart, including its chambers.

Because the heart isn't yet developed, the American College of Obstetrics and Gynecologists (ACOG) defines this movement as "cardiac activity" rather than a heartbeat.

"What pregnant people may hear or see is the ultrasound machine translating electronic impulses that signify fetal cardiac activity into the sound that we recognize as a heartbeat," ACOG states. The group recommends waiting until the heart is fully formed before using the term "heartbeat."

A baby's heart is one of the first structures to form, because it's needed to deliver oxygenated blood and nutrients to other developing organs.

Some of the important steps in heart development are:

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• The heart tube twists and bends into an S shape, and the bottom of the tube moves up to form the two upper heart chambers (atria).
• The middle of the tube forms the two lower chambers (ventricles).
• Walls form to divide the chambers, each with an entrance and exit for blood flow.
• Valves form between the ventricles and the aorta (large blood vessel) and pulmonary artery.
• At about 10 weeks to 12 weeks, the heart is formed.
• Small blood vessels form and fill with blood.
• At birth, the opening between the two atria closes. Your baby is now getting oxygen from their lungs and not from the placenta.

What does a fetal heartbeat sound like?

Many women say that the beating of their baby's tiny heart sounds like galloping horses. The embryonic and fetal heartbeat is fast, about 110 to 160 beats per minutes.

If you hear a whooshing noise, that's not the heartbeat – it's probably because of movement or the monitor traveling past your placenta. Also, if you hear two heartbeats, don't assume you're having twins. You're likely hearing your own heartbeat in the background.

If the heart rate of the embryo or fetus is healthy, it's a sign that development is progressing normally. The chances of a miscarriage once you see or hear a heartbeat are less than 10 percent (at 6 weeks) and less than 1 percent at 9 weeks.

What if my provider can't detect a heartbeat?

If your doctor or midwife doesn't find your baby's heartbeat on your first-trimester ultrasound right away, it could be because:

• It's too early in your pregnancy. Your due date may be off. (This can happen, especially if your menstrual cycle was irregular.) Your provider will schedule another visit in a week or two.
• You have a retroverted uterus. Because of the position of your uterus, the baby can be just a little further away and harder to detect.
• You're overweight. Extra padding between the ultrasound wand and the baby may make it harder to detect the heartbeat.
• Miscarriage. If there's no heartbeat when expected (and ultrasound measurements confirm the age) or if cardiac activity was detected and now isn't, this may be a sign of miscarriage.
• Ectopic pregnancy. In this case, an ultrasound wouldn't pick up heart motion in the uterus because there's no embryo there. Although ectopic pregnancies are never viable, they can sometimes develop enough to have heart motion. An ectopic pregnancy is a surgical emergency that can be fatal if not treated quickly.

How will I usually hear my baby's heartbeat?

Your provider will check your baby's heart rate with a fetal Doppler (a handheld ultrasound monitor) at each prenatal visit after about 10 weeks.

The procedure is completely painless. Your doctor or midwife will cover the device with ultrasound gel and move it around on your belly until they find a spot where the heartbeat can be detected. The Doppler sends and receives sound waves that safely bounce off your insides, including your baby's heart. The returning sound waves are processed and amplified by the device so you and your provider can hear the heartbeat.

You can rent or buy a Doppler for home use. However, some experts think a home Doppler isn't a good idea.

That's because it can take considerable training and practice to find and correctly identify a baby's heartbeat. You may not be able to hear the heartbeat – not because of an issue with your baby, but due to user error. It's also possible to hear the sound of blood flowing through the placenta or your own blood vessels and mistake it for a heartbeat.

There are better ways to monitor your baby, such as paying attention to your baby's movements and attending all of your prenatal appointments.

Learn more:

• When will my pregnancy start to show?
• Pregnancy in weeks, months, and trimesters

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Karen Miles

Karen Miles is a writer and an expert on pregnancy and parenting who has contributed to BabyCenter for more than 20 years. She's passionate about bringing up-to-date, useful information to parents so they can make good decisions for their families. Her favorite gig of all is being "Mama Karen" to four grown children and "Nana" to nine grandkids.

How to calculate the due date. Calculate gestational age by week

Our online pregnancy calculator will help you calculate gestational age by week and find out when your baby will be born

Last period start date

dd.mm.yyyy

Determine the date of birth

It is impossible to calculate the date of birth with absolute accuracy. The estimated day of delivery is calculated as follows: the first day of the last menstrual period + 280 days . This is an average date, usually delivery occurs in the next plus or minus 10 days . Learn more about the calculation of the PDR.

I am pregnant

How to calculate due date

What is PDD?

EDD is an abbreviation commonly used by physicians for the phrase "estimated due date".

How is the estimated due date (ED)

How to correctly calculate the due date? Pregnancy from conception to the birth of a child lasts about 266 days, or 38 weeks. Since the date of conception, as a rule, is not exactly known, in modern obstetrics it is customary to calculate the gestational age from the first day of the last menstruation, i.e. you need to calculate the date of birth by menstruation. With this calculation, it is approximately 280 days, or 40 weeks, since ovulation and, accordingly, fertilization usually occur two weeks after the start of the cycle. Ultrasound equipment is also set up for the same calculation of the gestational age, therefore, if menstruation is delayed by 4 weeks, the doctor will most likely report 8 weeks of pregnancy (whereas only about 6 weeks have passed from the moment of conception).

Accuracy of due date calculation

How to calculate exact gestational age? You can calculate the approximate date of birth of a child if you know the date of the last menstrual period. The estimated due date (EDD) will be 280 days (40 weeks) after the first day of your last period. However, only 5% of children with normal pregnancies are born on the “calculated” day, another 85% are born within a period of plus or minus a week from this date, and another 10% are “late” or “hurry” for another week. It is believed that a healthy pregnancy can last from 38 to 42 weeks.

Duration of pregnancy

How to correctly calculate the duration of pregnancy? The duration of pregnancy depends on many factors, including the individual pace of development of the child, as well as the duration of the woman's menstrual cycle. So, for example, if the cycle duration is less than 24 days, then childbirth can occur 10-15 days earlier than when calculated according to the formula "1st day of the last menstruation + 280 days", while the child will be fully mature and healthy. And if the menstrual cycle lasts more than 32 days, then the pregnancy can drag on for 10-15 days, and this will not be considered overdose.

The calculator was developed in accordance with the recommendations of Ph.D. obstetrician-gynecologist Tatyana Solomatina, author of the book "Advice to those who have flown."

Gestational age. Date of birth. Calculate gestational age and due date

CONTENTS

1. What is a calculator?
2. How does the calculator work?
3. Other ways to determine and confirm the due date.
4. How accurate is the calculator?

What is a calculator?

In most cases, women do not know the exact date of conception, but they can with great certainty to say when the last menstrual cycle began. First the day of the last menstruation is the starting point. Well, then pregnancy calculator comes into play - a program that makes a lot of calculations for you and answering almost all questions of interest to the expectant mother :

• when was the conception approximately;
• what is the estimated date of delivery;
• what is the exact week now and how much time is left until delivery;
• how a child develops, what size it is, what it already does in the womb and what skills it has.

Calculator free, always available online, easy to use, has concise and understandable interface, will not let you make arithmetic errors and displays results in a visual and interesting way. In addition, you can always check the accuracy calculator, independently making calculations according to well-known obstetric techniques, which we present below.

To calculate the gestational age and the expected date of delivery, a woman needs to enter in the calculator, only the date of the first day of the last menstruation (LPM) in the format "day month Year". If you enter the last day of your period or a known date conception, the calculator will show completely different results, you need to enter exactly the start date last menses.

The calculator calculates the obstetric period - this is when the first day of menstruation is considered like the first day of pregnancy. It is by obstetric term that gynecologists track the development fetus, prescribe tests and examinations.

The gestational age in the calculation results of the calculator is shown in weeks, this is the most simple and convenient interval. There are other generally accepted intervals for dividing such a large period - months (10 lunar months of 28 days) and trimesters. The trimesters divide the process intrauterine gestation into three phases of 13 weeks each.

The results display the exact period in weeks and days, a brief description of the development of the fetus, the height and weight for the calculated week are indicated, which organs are being formed, what can already be felt and do baby. A link is provided to the full article with colorful illustrations, telling about the condition of the fetus and mother, tests and examinations, recommended diet, possible problems and ways to overcome them. You will always know what to prepare for.

This calculation displays both fetal ages: the so-called "gestational" fetal age (menstrual), which is different from the so-called "ovulation" age (fertilization), it is two weeks less and is counted from the estimated date of conception. Therefore, all the details fetal development and well-being of women are considered from week to week, starting precisely from the third week.

In addition, you will know how many days are left before childbirth, under what sign of the zodiac and in what year of the Chinese calendar your baby will be born, by clicking on additional links you can determine the color of the eyes, the blood type of the child.

Depending on the week, additional links are displayed to calculators for checking ultrasound results, hCG hormone levels, blood test results, weight gain rates. If you wish, you can calculate an individual calendar of analyzes and examinations, both for mother and child.

Starting in the second or third trimester, you can find out about your benefits and calculate your benefits. amounts. For working mothers, it is possible to determine the date of maternity leave and find out if you are entitled to annual leave leave before the decree.

Whatever week you are, the calculator will offer you to test your knowledge using interactive tests "Care of a newborn", "Feeding of newborns", "Tests and examinations of pregnant women", "Rights of pregnant women". You will just have time to fill in the gaps and improve your knowledge on these important topics.

The calculator will also calculate the estimated date of conception of the child, according to which, using Chinese gender calendar, you can find out who you will be - a girl or a boy. According to the results of the ultrasound, it will be interesting to know whether the prediction came true.

How does a calculator work?

All calculations of our calculator are based on the obstetric calculation method, as the most accurate, scientifically based and universally accepted method for calculating gestational age. other methods, for example, a report from the day of intercourse or from ovulation cannot be considered reliably accurate due to the characteristics of the reproductive system.

The length of the cycle may differ for different women, one has 21 days, the other has 34, moreover, in the same woman, the cycle may be irregular and fluctuate in duration during years for various reasons. On average, most women have a menstrual cycle is 28 days.

But one thing is common to all: conception of a child is possible only during ovulation - if there is no mature egg, then conception will not occur.

At the beginning of the cycle, a follicle forms on the surface of the ovary, inside which the female matures. sex cell. In the middle of the cycle, the follicle sac ruptures under the influence of strictly defined hormones. and allows spermatozoa access to the oocyte.

After ovulation, the female gamete lives from 24 to 36 hours, at which time conception must occur, otherwise the cell dies. This process is repeated every cycle.

It turns out, regardless of the length of the cycle, nature allocates only one or two days for the process of conception. However, this does not mean that sexual intercourse can lead to pregnancy only during the hours when the oocyte lives. No, due to the ability of spermatozoa to survive for a long time in the female body, sex even 3-4 days before release the egg can lead to fertilization immediately after its release from the follicle. With active sexual life in general it is impossible to determine whether sexual intercourse before, during or after ovulation led to conception.

Therefore, in obstetric practice, it is generally accepted that conception occurs during the period of ovulation - 14 days before before the end of the menstrual cycle. And again, we are faced with a harsh reality here - a woman ovulates can happen both earlier and later than the above day. Based on all this, it is customary to count from the date of the last menstruation, this is both easier, and the woman usually remembers this date.

Thus, according to the obstetric standard, the first day of the last menstruation is the first day pregnancy, and the day of conception falls approximately at the end of the second week. If a woman finds out about the delay, then this is already the 4th week and the gynecologist, regarding a week-long delay, is already setting a deadline of 5 weeks.

Our online calculator is based on this obstetric method. Weeks are normal calendar months, and obstetric months, each of them has exactly 4 calendar weeks.

Pregnancy lasts an average of 40 weeks or 10 obstetric months well-known 9 months . 1 2 3 4 5 6 0128 8 9 10 11 12 13 14 15 16 17 18 19 20 II 21 22 23 24 25 26 27 28 29 30 III 31 32 33 34 35 36

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