IVF Due Date Calculator: Based on Your Embryo Transfer

Why IVF dating is different

In a natural pregnancy, the due date is estimated from your last period and an average ovulation day. With IVF there’s no need to estimate: the day your eggs were retrieved and fertilized, and the embryo’s age at transfer, are known. The American College of Obstetricians and Gynecologists (ACOG) recommends dating IVF pregnancies from this information.

Day 3 vs day 5 transfers

The calculator adds these intervals to your transfer date, depending on the embryo’s age:

The difference comes from the embryo’s age: on transfer day a day 5 embryo is two days further along than a day 3 embryo, so the due date is two days earlier.

Frozen embryo transfers work the same way: what matters is the embryo’s age when it was frozen and the date it was transferred.

Using your egg retrieval date

If you don’t have your transfer date to hand but know your egg retrieval date, choose “Egg retrieval date.” Eggs are fertilized on the day they’re collected, so that date is treated as the date of conception, the same logic as our conception date calculator.

The “last period” question on forms

An IVF pregnancy may not have a natural last period, but hospital forms and pregnancy apps will still ask for one. Because pregnancy weeks are always counted from a period date, IVF pregnancies use an equivalent last period date worked back from the transfer. The calculator shows it, so your weeks line up across your clinic, your OB-GYN and any apps you use.

Twins

Twins are more common after IVF. The estimated due date is calculated the same way, but twins usually arrive before it. Your provider will plan monitoring and delivery with you.