Question 1

Why is IVF due date calculation different?

Accepted Answer

With IVF, we know the exact date of fertilization (egg retrieval) and embryo transfer, making the calculation more precise than natural conception where ovulation date is estimated. IVF due dates use the retrieval or transfer date rather than last menstrual period.

Question 2

Should I use retrieval date or transfer date?

Accepted Answer

Either works if calculated correctly. Retrieval date = add 266 days (38 weeks). For transfer date: Day 3 embryo = add 263 days, Day 5 blastocyst = add 261 days. Both methods should give you the same due date.

Question 3

What is the adjusted LMP for IVF?

Accepted Answer

Your adjusted LMP is a calculated date used for pregnancy dating. For a Day 5 transfer, subtract 19 days from your transfer date. For Day 3 transfer, subtract 17 days. For retrieval date, subtract 14 days. This adjusted LMP is what doctors use to track gestational age.

Question 4

Will my due date change at ultrasound?

Accepted Answer

Due dates from IVF calculations are very accurate since timing is known precisely. However, if early ultrasound measurements differ significantly (more than 5-7 days), your doctor may adjust the due date. Small differences are normal and usually don't change the due date.

Question 5

How accurate is an IVF due date?

Accepted Answer

IVF due dates are more accurate than natural conception dates because we know exactly when fertilization occurred. However, only about 5% of babies arrive on their due date. Most arrive within 2 weeks before or after.

Question 6

Does frozen embryo transfer affect due date calculation?

Accepted Answer

No, the calculation is the same whether using fresh or frozen embryos. What matters is the embryo age at transfer (Day 3 or Day 5) and the transfer date itself. The freezing process doesn't change gestational age calculations.

How do I calculate my due date after IVF?

IVF Due Date Calculator

Calculate Your Due Date

How IVF Due Dates Are Calculated

Using Transfer Date

Using Retrieval Date

Track Your Pregnancy Journey

Frequently Asked Questions