HEALTH · IVF DUE DATE
IVF Due Date Calculator
Calculate your estimated due date from your IVF embryo transfer date. Supports day-5 blastocyst, day-3 cleavage, and day-0 fresh transfers with ACOG / ASRM formula.
Based on ACOG / ASRM guidance: EDD = transfer date + 261 days (conception + 266 days − 5 days embryo age).
About This Calculator
IVF due dates are calculated differently than natural-conception due dates because the embryo's exact age is known from the retrieval or thaw date. This calculator uses the ACOG / ASRM method: EDD = transfer date + (266 − embryo age in days), since human gestation is 266 days from fertilization and the embryo was already living for 3 or 5 days before transfer.
How It Works
Enter your embryo transfer date and select the embryo age at transfer: day 5 (blastocyst — the most common in modern IVF), day 3 (cleavage stage), or day 0 (fresh same-day transfer). The calculator adds the remaining days to a full-term 266-day gestation and shows your estimated due date and current gestational age.
The Formula
EDD = transfer_date + (266 − embryo_day)
- transfer_date
- date of embryo transfer to the uterus
- embryo_day
- age of embryo at transfer in days (0, 3, or 5)
Frequently Asked Questions
- Why is the IVF due date different from a natural-conception due date?
- In natural conception, the fertilization date is estimated (ovulation + ~12 hours). In IVF, the retrieval date is day 0 of the embryo's life, so the gestational age at transfer is exact. The formula subtracts the embryo's age from the standard 266-day gestation window, giving a more precise estimate than the LMP-based Naegele's Rule used for natural conceptions.
- What if I had a frozen embryo transfer (FET)?
- Use the same transfer date — the date the embryo was placed in the uterus, not the original retrieval or freeze date. Day 5 blastocyst is the most common FET; select day 3 if your clinic transferred a cleavage-stage embryo. The calculator works identically for fresh and frozen transfers.
- How accurate is an IVF due date?
- IVF due dates are typically more accurate than LMP-based estimates because fertilization date is known precisely. However, all due dates are estimates — only about 5% of babies are born on their calculated due date. Your reproductive endocrinologist or OB will confirm or adjust dating with ultrasound at 8–14 weeks.