Pregnancy date of birth 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

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

Pregnancy tests: How soon can you get a positive pregnancy test?

Pregnancy tests work by detecting the presence of a hormone called human chorionic gonadotropin (hCG) in your urine. Some home pregnancy tests claim they're sensitive enough to give a positive result as early as five days before you would expect your next period. But you're more likely to get an accurate result (and avoid a false negative pregnancy test) if you wait to test until after the first day of your missed period.

How soon can you take a pregnancy test?

You're more likely to get an accurate result if you wait a few days to a week after you expect your period before taking a pregnancy test.

Some home pregnancy tests claim they're sensitive enough to give you a positive result as early as five days before you would expect your next period. And some women will have produced enough hCG to get a positive result at that point. So if you're anxious to know, go ahead and try it. If you get a negative result, you can just wait and test again later if you still haven't gotten your period.

Most home pregnancy tests claim to be accurate on the day you miss your period, but even then, the amount of hCG in the urine at this time can vary a great deal from one woman to another.

If you test too soon, you may get a false negative pregnancy test (a negative result even if you are pregnant) or an unclear result like a faint line on a pregnancy test.

How do pregnancy tests work?

Home pregnancy tests tell if you're pregnant or not by detecting the presence of hCG in your urine.

This hormone is produced by cells that will develop into the placenta. It first enters your bloodstream when the fertilized egg starts to implant in the lining of your uterus, as early as six days after fertilization.

The amount of hCG in your body then increases rapidly over the next few weeks, often doubling every two days or so. When a pregnancy test detects the hormone in your urine, it shows a positive result.

Home pregnancy tests are now about 99 percent accurate, when done correctly. And there's no reason to pay more for one test over another. As long as a test isn't expired, it should be equally as accurate as another test.

What will differ between tests is their sensitivity. Detecting hCG in the urine of someone 6 months pregnant (when there's plenty of hCG) versus 6 days past ovulation (when there's a very small amount of hCG) are two very different tasks. The ability of a test to pick up small amounts of hCG in your urine depends on the sensitivity of the test.

It's not always easy to tell which tests are the most sensitive. New products come out frequently, and manufacturers can make improvements at any time.

But some package inserts provide information about a test's sensitivity – that is, they report the lowest concentration of hCG in milli-International Units per milliliter (mIU/ml) of urine that the test can detect. For example, a pregnancy test that claims to be able to detect hCG at 20 mIU/ml should be more sensitive than one that claims to detect it at 50 mIU/ml.

How do I use a home pregnancy test?

For best results when using a home pregnancy test:

• Make sure the test is current. Check the expiration date on the package, especially if you've had it for a while. If you've been storing the test anywhere that gets moist or warm, like the bathroom, it may have deteriorated. If that's the case, it's better to throw it away and get a new one.
• Test first thing in the morning. Your urine is most concentrated when you first get up, so hCG levels (if present) will be easier to detect at that time.
• Read the directions carefully. Directions vary with different brands. Some require you to urinate in a cup and then use the dropper provided to place a small sample in the testing well. With others, you can pee directly onto the testing device. And some let you do either.

The tests also vary in how they display the results. For example, some show pink or blue lines on the test strip, while others reveal a red plus or minus sign in a window. "Digital" tests tell you in words whether you're pregnant. Most have a control indicator (often a second line or symbol) to indicate whether the test is valid.

It may take up to 10 minutes to see results. If the control indicator doesn't show up properly, the test may be faulty. If this happens, you can usually call the manufacturer and have them send you a new one (though it probably won't arrive soon enough to use that same month).

If you have questions about how to use a test, call the manufacturer's toll-free number on the package instructions.

If the test shows a negative or a faintly positive result, wait another few days or a week and try again if you still haven't gotten your period. One possibility is that you ovulated later in your cycle than you thought and took the test too early to get a positive result.

Don't assume that one negative result means you're not pregnant. The amount of hCG produced is different for every woman and varies with each pregnancy. If you suspect that you're pregnant (for instance, if you're having early pregnancy symptoms) and still have a negative test, repeat a urine pregnancy test in a week if you still haven't gotten your period.

If you still haven't gotten either your period or a positive result two weeks or so after you would expect it, contact your healthcare provider.

False positive pregnancy tests

A false positive pregnancy test means that you get a positive result, but aren't pregnant. These are uncommon, but they can happen under certain circumstances:

• You had a miscarriage or a pregnancy termination in the previous eight weeks or have a molar pregnancy.
• You've taken a fertility drug containing hCG (used to induce ovulation in fertility treatments).
• You have a rare medical condition, such as an hCG-secreting tumor.
• You're using an expired or faulty test.
• You're experiencing menopause or perimenopause.

If you have an early positive result and then get your period soon after, you may have had what's sometimes called a chemical pregnancy. This means a fertilized egg implanted in your uterus and developed just enough to start producing hCG, but then stopped developing for some reason. This form of early pregnancy loss usually happens when the fertilized egg has defects that prevent it from growing normally.

After a chemical pregnancy, your period may be a little heavier and a few days later than usual.

Note: An ectopic pregnancy usually results in a positive pregnancy test, even though these pregnancies show slower hCG rises. No matter what result you get from a pregnancy test, call your healthcare provider right away if you:

• Feel dizzy or faint.
• Have abdominal pain (especially a sharp or stabbing pain in your abdomen or on one side of your pelvis).
• Have abnormal bleeding.

Pregnancy blood tests

Most healthcare providers use a urine pregnancy test, just as you would at home – but your provider may use a blood test instead. It takes anywhere from an hour to a day or more to get the results.

There are two types of pregnancy blood tests:

• A qualitative hCG blood test simply detects whether there is hCG in your blood. It will give pregnancy results at about the same time as a urine test. The results return as "positive" or "negative."
• A quantitative blood test (beta hCG test or serum test) measures the exact amount of hCG in your blood. The results return as a number. This test is very accurate. It can detect hCG as early as six to eight days after ovulation, about a week before your period is due. It takes longer to get results from a quantitative blood test, though.

Some testing companies will let you pay online and then go to a lab and have a blood sample taken. The testing company will provide you with your result the next day by phone or online. These tests start at about $40. If you decide to use one of these companies rather than going through your healthcare provider, be sure to find out which type of blood test they're using.

What to do after a positive pregnancy test

Some women take more than one pregnancy test (or several) just to be sure – but that's not necessary. Once you've gotten a positive pregnancy test, call your healthcare provider to set up a prenatal visit or to discuss your options if you're uncertain about continuing the pregnancy.

For prenatal care, providers typically schedule the visit for when you're at least 8 weeks pregnant, but it varies. Some will see you sooner, particularly if you have a medical condition or have had problems with a pregnancy in the past. It's especially important to see a provider soon if you're having nausea and vomiting, vaginal bleeding, or abdominal pain.

If you don't already have a family doctor, ob-gyn, or midwife, do some research and ask for recommendations. But don't delay your care while searching for a good fit, because you can always switch providers later. At your first prenatal visit, your provider will take your health history, explain your options, and more.

Learn more:

• I'm pregnant – now what?
• Implantation bleeding
• Pregnancy symptoms

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. The 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. Not, 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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