First 24-hour interval of concluding menstruum

Most pregnancies last effectually forty weeks (or 38 weeks from conception), so typically the all-time way to judge your due date is to count 40 weeks, or 280 days, from the commencement day of your terminal menstrual menstruation (LMP). You could also decrease three months from the first day of your last period and add vii days.

The first twenty-four hour period of your LMP is how most health care providers estimate a infant'south due date. Only call back, it'south only an estimated due engagement, not a deadline for your baby to go far. Only 4 percent of babies are born on their estimated due date.

Conception date

If you lot've been tracking ovulation symptoms or have been using ovulation exam strips, then you may be able to use your conception appointment to summate your pregnancy due date. Just add together 266 days to get your estimated due date (or select "Formulation Date" from the menu above, and let our Due Date Calculator do the math for you).

IVF transfer date

If y'all conceived through in vitro fertilization (IVF), you can calculate your due engagement using your IVF transfer date. Near embryo transfers occur either three days or v days after egg retrieval and fertilization. If you had a day-three transfer, count 263 days from the transfer appointment to summate your due appointment, and if you had a day-5 transfer, count 261 days. (Or select "IVF" from the menu higher up.)

Ultrasound browse

Even if you can't pinpoint when you conceived, forget the day of your last menstrual period or aren't sure when ovulation occurred, other clues can help you and your practitioner determine your due engagement at your outset prenatal appointment, including:

  • An early ultrasound, which can more than accurately engagement the pregnancy. Just be aware, all the same, that not all women go an early ultrasound. Some practitioners perform them routinely, but others just recommend one if your periods are irregular, you're 35 or older, you have a history of miscarriages or pregnancy complications, or the due engagement tin can't be determined based on your concrete exam and LMP.

  • Pregnancy milestones such as the first time the infant'southward heartbeat is heard (around week nine or ten, though it can vary) and when you beginning experience fetal move (on average between 18 and 22 weeks, just it can be earlier or later), tin requite clues every bit to whether your due date is authentic.

  • Your fundal tiptop, which is the measurement from your pubic bone to the top of your uterus, is checked by your practitioner at each prenatal visit and helps confirm your due date.

  • The size of your uterus, which will be noted when your initial internal pregnancy exam is performed, tin can as well be a cistron in pinpointing the EDD.

Can I plan my due date?

Whether you're trying to avoid being very pregnant in the middle of summer or are a instructor who wants to maximize time off with your petty one, yous can try to time when you conceive in order to "plan" your due appointment. Merely even if you're one of the lucky ones who's able to get pregnant when she really wants to, just call up that you lot probably won't be able to map out exactly when you'll requite birth to the twenty-four hours (or even the week or month!).

Still, you can attempt our Ovulation Estimator, which uses the engagement of your concluding menstrual period and your typical wheel length to discover the days yous're most likely to be fertile and increase your chances of conceiving.

Can my due date alter?

Yep, your due engagement tin can modify. While it's definitely not a reason to worry, your doctor may change your due appointment for a number of reasons every bit your pregnancy progresses.

It may be that yous take irregular periods and your early ultrasound dating was off, or that your first ultrasound was in the second trimester.

Information technology could also be because your fundal peak is abnormal, or your levels of alpha-fetoprotein (AFP), a protein made by the baby, are outside the usual range. Talk to your practitioner if you have whatsoever questions or concerns.