First mean solar day of final period

Most pregnancies last around 40 weeks (or 38 weeks from conception), so typically the all-time way to gauge your due engagement is to count 40 weeks, or 280 days, from the first day of your last menstrual period (LMP). You could also decrease iii months from the first 24-hour interval of your concluding period and add seven days.

The first day of your LMP is how almost health intendance providers gauge a baby's due date. Just remember, information technology's only an estimated due engagement, not a deadline for your baby to arrive. But 4 percentage of babies are built-in on their estimated due date.

Formulation engagement

If you lot've been tracking ovulation symptoms or have been using ovulation test strips, and then you may be able to use your conception date to calculate your pregnancy due date. Just add 266 days to go your estimated due date (or select "Formulation Appointment" from the menu above, and let our Due Date Calculator exercise the math for y'all).

IVF transfer date

If you conceived through in vitro fertilization (IVF), you lot can calculate your due appointment using your IVF transfer date. Most embryo transfers occur either three days or five days after egg retrieval and fertilization. If you had a twenty-four hour period-three transfer, count 263 days from the transfer date to calculate your due appointment, and if you had a day-5 transfer, count 261 days. (Or select "IVF" from the menu above.)

Ultrasound scan

Even if y'all can't pinpoint when yous conceived, forget the day of your last menstrual period or aren't sure when ovulation occurred, other clues tin can assist yous and your practitioner determine your due date at your commencement prenatal appointment, including:

  • An early ultrasound, which can more accurately date the pregnancy. Just be aware, however, that non all women get an early ultrasound. Some practitioners perform them routinely, but others merely recommend one if your periods are irregular, you're 35 or older, you have a history of miscarriages or pregnancy complications, or the due date can't be determined based on your physical exam and LMP.

  • Pregnancy milestones such equally the kickoff fourth dimension the babe's heartbeat is heard (around calendar week 9 or 10, though it can vary) and when you lot showtime feel fetal motility (on average between eighteen and 22 weeks, but it can be earlier or later), tin requite clues as to whether your due engagement is accurate.

  • Your fundal height, 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 examination is performed, tin can too be a factor in pinpointing the EDD.

Can I plan my due engagement?

Whether you lot're trying to avert existence very pregnant in the middle of summer or are a teacher who wants to maximize time off with your little one, yous can effort to time when you lot conceive in order to "programme" your due appointment. But even if y'all're one of the lucky ones who's able to get meaning when she really wants to, only recall that yous probably won't be able to map out exactly when you'll give birth to the day (or even the week or month!).

Nevertheless, you can attempt our Ovulation Calculator, which uses the engagement of your last menstrual menstruation and your typical cycle length to observe the days you're well-nigh likely to be fertile and increase your chances of conceiving.

Can my due date alter?

Yep, your due date can change. While it's definitely not a reason to worry, your doc may change your due date for a number of reasons as your pregnancy progresses.

Information technology may exist that yous have irregular periods and your early ultrasound dating was off, or that your outset ultrasound was in the 2nd trimester.

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