IVF Due Date Calculator
Calculate your due date after IVF from the embryo-transfer or egg-retrieval date — for day-3 and day-5 (blastocyst) transfers.
How it works
Day-5 transfer: due = transfer + 261 days · day-3 transfer: due = transfer + 263 days · egg retrieval: due = retrieval + 266 days.
IVF removes the guesswork of ovulation timing, so due dates are more precise than with a natural cycle. The fertilization date is known, and the embryo’s age at transfer is fixed, so counting forward gives the due date directly: a day-5 blastocyst is already five days past fertilization, so 261 days remain to 40 weeks; a day-3 embryo has 263; and from egg retrieval (fertilization day) the full 266 days apply. The result equals a 280-day, 40-week pregnancy measured from the equivalent last-period date.
Worked example
A day-5 embryo transfer on June 15, 2026 plus 261 days gives an estimated due date of March 3, 2027 — equivalent to a last period around May 27, 2026.
Frequently asked questions
Why does the number of days differ by transfer day?
The count reflects how old the embryo already is. A day-5 blastocyst has used up five of the days between fertilization and birth, a day-3 embryo three, so fewer remain to reach 40 weeks.
Is an IVF due date more accurate than a natural one?
Usually yes, because the exact fertilization and transfer dates are known rather than estimated from a cycle. An early ultrasound is still used to confirm dating.
Does a frozen (FET) transfer change the calculation?
No — what matters is the embryo’s age on the day it is transferred, so a frozen day-5 blastocyst uses the same 261-day count as a fresh one. Use the transfer date, not the original retrieval date.
Related calculators
Educational estimates from standard formulas and population averages — every pregnancy and baby is different. This is not medical advice; your doctor, midwife or pediatrician, with an examination or ultrasound, gives the accurate guidance.