IVF Due Date Calculator
IVF due date calculator for fresh or frozen transfers of a day 3, 5 or 6 embryo, or from egg retrieval or IUI, plus how many weeks pregnant you are today.
Written by HealthSensibly Editorial TeamReviewed by the HealthSensibly editorial teamUpdated
Working out a due date after IVF
In IVF the fertilisation date is known for certain, which makes the due date more precise than in a natural conception. The calculator adds back the embryo’s age at transfer so the result matches the standard 40-week (280-day) count used for pregnancies dated from a “last period”. The sum is identical for fresh and frozen (FET) transfers.
| Date you have | Due date = |
|---|---|
| Day-3 embryo transfer | Transfer date + 263 days |
| Day-5 blastocyst transfer | Transfer date + 261 days |
| Day-6 blastocyst transfer | Transfer date + 260 days |
| Egg collection (fertilisation) date | Retrieval date + 266 days |
| IUI date | IUI date + 266 days |
Depending on how they count, your clinic’s date might be a day or two different, and your obstetrician may fine-tune it after the first-trimester scan.
Keep track week by week with the pregnancy week calculator, and plan meals with our diet plan for each trimester.
Common questions
Does a frozen transfer change the calculation?
No. With a frozen embryo transfer (FET) you enter the day of transfer plus how old the embryo was (day 3, 5 or 6), exactly as you would for a fresh one.
On transfer day for a day-5 embryo, how pregnant am I?
Roughly 2 weeks and 5 days, since dating assumes a period started about 2 weeks before fertilisation.
Do IVF pregnancies tend to deliver early?
The chance of preterm birth is a little higher with IVF, particularly with twins. Most single IVF babies are born near their due date.
Which date should I enter after IUI?
Use the IUI date; the calculator adds 266 days, the same as for a known fertilisation date.
References: ACOG: Methods for estimating the due date · NHS: IVF
Checked against the sources listed above. This is general health information and not medical advice — please ask your doctor or a registered dietitian what suits you.
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