IVF due date calculator for 3-day, 5-day and frozen transfers.

How the IVF due date is calculated

The standard due date counts 280 days from the first day of the last menstrual period. ACOG notes this is by convention and assumes ovulation on day 14. With IVF the fertilization date is known, so ACOG says the due date should be assigned using the age of the embryo and the date of transfer. This tool does that arithmetic.

Fertilization sits 14 days into the 280, so a due date is fertilization + 266 days. An embryo that is N days old on transfer day was fertilized N days earlier, so due date = transfer date + 266 − N. The 266 and the three offsets below are this tool's own derivation from ACOG's 280-day convention.

• Current week: gestational age is counted as if the pregnancy began 14 days before fertilization, the same way as a last-period count, so the week shown matches how clinics count.
• Trimesters: first trimester to 13 weeks 6 days, second from 14 weeks 0 days, third from 28 weeks 0 days (common convention).
• hCG test window: transfer + 9 to 14 days, shown as typical timing only. It is not from ACOG, and your clinic sets the actual date.
• The tool runs in your browser. Nothing you enter is sent anywhere or stored.

Sources (opened 2026-10-02): ACOG Committee Opinion No. 700, Methods for Estimating the Due Date (280-day convention; IVF due date from embryo age and transfer date). Background: CDC, Assisted Reproductive Technology; ASRM patient resources.

FAQ

How do you calculate a due date after IVF?

Take the transfer date, add 266 days, then subtract the age of the embryo in days. A day 5 embryo gives transfer + 261 days, a day 3 embryo gives transfer + 263 days, and a day 6 embryo gives transfer + 260 days. ACOG says an IVF due date should be assigned using the age of the embryo and the date of transfer. Your clinic's date is the one to use.

Is the due date the same for a frozen embryo transfer?

The arithmetic is the same: what counts is the age of the embryo when it was frozen and transferred, not the date the cycle started. A day 5 blastocyst transferred in a frozen cycle still gives transfer + 261 days. Check with your clinic which embryo age they record.

What if I only know my egg retrieval date?

This tool treats the retrieval date as day 0 of the embryo and adds 266 days. That is an approximation, because fertilization usually happens within a day of retrieval, so it can be off by a day.

When is the beta hCG blood test after a transfer?

Many people are told to test roughly 9 to 14 days after transfer. That range is shown here as typical timing only, and it is not from ACOG. Your clinic sets the actual date, so follow their instructions.

Why is the IVF due date different from a due date based on my last period?

The usual due date counts 280 days from the first day of the last period (ACOG, by convention), assuming ovulation on day 14. With IVF the fertilization date is known, so the calculation starts there: 266 days from fertilization, which is the same 280 days minus those 14 days.

Will my baby arrive on the due date?

Probably not exactly. A due date is an estimate, and your care team may adjust it, for example after an early ultrasound. This tool is arithmetic only and gives no medical advice.