Fertility Blog by Illume Fertility

How to Calculate Your Due Date After IVF Embryo Transfer

Written by Monica Moore, MSN, APRN | July 19, 2024

Ask Monica is a Q&A video series hosted by Nurse Practitioner Monica Moore.

In this article:

Feeling confused about what your due date would be after you conceive through IVF? Let's break down some easy ways to calculate this exciting date.

What's my due date after an embryo transfer?

Monica Moore:
- Hi, everyone. Monica Moore here, nurse practitioner at the Illume Fertility. And today on this session of "Ask Monica", we're gonna talk about how to figure out your due date, should you become pregnant after an IVF cycle. So the due date really is the transfer date, plus 266, minus the age of the embryo, which for most people is gonna be five. So it's a transfer date, plus 266, minus five. We don't figure, if you get a pregnancy, if you achieve a pregnancy and you're not doing IVF, then what your doctor would ask you is when was the first day of your last period? Well, whenever you do a fertility cycle, we sort of manipulate your days. We might put you on birth control pills or other medications. So we cannot rely on the last menstrual cycle. So what we do know is the day that you got your trigger shot, the day that you had a retrieval. So if you're doing a fresh transfer, the date you had a transfer. If you're doing a frozen embryo transfer, or you're doing a pregnancy using donor eggs, you just have the transfer, you don't have the retrieval or the HCG injection. So we try to figure it out these days by transfer date. So if you had, let's say, a day-five transfer, then which most people have, if you had PGTA, which is the genetic testing of the embryos, you had a day-five transfer, then you count 261 days after your transfer date. This date might be, even though we know the date for sure, then once you have an ultrasound pregnancy, early ultrasound is very good and helpful for calculating the due date and the embryo age, even though we know what it is from having IVF, we would be measuring what's called the crown run length or the head to butt sort of the embryo or early fetus to then compare to your due date to make sure that everything is sized appropriately. What you might see is us something with these handy dandy pregnancy wheels, which we get. And when we're talking to you, we would then calculate your due date based on your transfer date, which obviously we would know. And like I said, it would be transfer date plus 261 days if you have a day-five embryo. If you have a day-three embryo, obviously, it would be your transfer date plus 263 days. So if you're ever not sure, I know online, you can do a calculator for this. You would Google calculate your due date after IVF. But we help you obviously figure it out. You can ask us as early on, and then during your pregnancy, ultrasounds or scans. We correlate the health of the pregnancy with the size of the embryo growing appropriately, according to when we know your due date is, and what we should be seeing on that early ultrasound. So I hope this is helpful. Thanks so much. See you on the next episode.

Hi, everyone. Monica Moore here, nurse practitioner at Illume Fertility. On this episode of Ask Monica, we're going to talk about how to figure out your due date, should you become pregnant, after transferring an embryo in an IVF cycle.

If you became pregnant on your own (without the help of IVF), your doctor would ask you, "When was the first day of your last period?" in order to calculate your due date.

The Difference Between Spontaneous Pregnancy & IVF Pregnancy

As you may have guessed, calculating your due date requires a slightly different approach when you've conceived via in vitro fertilization (IVF). With IVF, the estimated date of your baby's arrival will be based on your embryo transfer date.

Most embryo transfers happen either three days or five days after egg retrieval and fertilization, if using your own fresh or frozen embryos. Day 5 embryo transfers are the most common, as this phase of development is ideal for implantation.

How to Calculate Your Due Date After IVF

  • For a Day 3 embryo transfer, count 263 days from your transfer date or add 266 days to your transfer date, then subtract three days (the age of the embryo).
  • For a Day 5 embryo transfer, count 261 days from your transfer date or add 266 days to your transfer date, then subtract five days (the age of the embryo).

Why are IVF pregnancies different?

Whenever you go through fertility treatment, we have to manipulate your menstrual cycle.

We might put you on birth control pills or other medications in order to time each step of the treatment process properly. So we cannot rely on the date of your last menstrual cycle when calculating your baby's due date. What we do know is the day that you got your trigger shot and the day that you had your egg retrieval.

Note: If you're doing a frozen embryo transfer (FET) or using donor eggs, you'll just have the transfer, you won't have an egg retrieval or take an hCG injection (trigger shot). 

[cta1]


Will my due date change after ultrasound?

Early pregnancy ultrasounds are very helpful for calculating both your due date and the age of your embryo - even when we already know what it is!

Your ultrasound technician or doctor will begin measuring what's called the "crown to rump" length (from the head to the butt of the fetus). They will then compare that information to your estimated due date and make sure that everything is developing as expected.

You might see us use something like one of these handy-dandy pregnancy wheels when we're talking to you to help calculate your due date based on your transfer date. 

We're Here to Help

If you're still feeling confused, there are various IVF due date calculators online that will do the math for you! Your doctor or nurse will also be happy to help you figure it out and confirm the correct estimated due date (EDD).

You can ask your team for clarification early on in your pregnancy. We correlate the health of the pregnancy with the size of the embryo (according to when we know your due date is) and what we expect to see on those early ultrasounds.

So, I hope this is helpful. Thanks so much.

Have a question about fertility?

Submit it here and we'll answer it in a future episode of Ask Monica!