IVF due date calculator
Choose the embryo's age at transfer (day 3, 5 or 6) or use the egg retrieval date. Works the same for fresh and frozen transfers.
Pick a date to see your due date.
IVF due date formulas
| Starting point | Due date | Equivalent "LMP" |
|---|---|---|
| Egg retrieval / fertilisation | + 266 days | 14 days earlier |
| Day 3 embryo transfer | + 263 days | 17 days earlier |
| Day 5 blastocyst transfer | + 261 days | 19 days earlier |
| Day 6 blastocyst transfer | + 260 days | 20 days earlier |
Clinics convert the transfer into an equivalent last-period date so that IVF pregnancies can be tracked on the same week-by-week charts as any other. ACOG's Committee Opinion 700 recommends dating assisted-reproduction pregnancies from embryo age and transfer date. Once you know the date, follow along with pregnancy week by week, and use the hCG doubling calculator to compare your beta results.
Frequently asked questions
How do you calculate a due date after a day 5 transfer?
Add 261 days to the transfer date. A day 5 blastocyst is already 5 days past fertilisation, and pregnancy lasts about 266 days from fertilisation, so 266 − 5 = 261. Equivalently, your "LMP date" is 19 days before the transfer.
What about a frozen embryo transfer (FET)?
The calculation is the same as a fresh transfer. What matters is the embryo's developmental age at transfer (day 3, 5 or 6), not when it was frozen.
Is an IVF due date more accurate?
The date of conception is known exactly, so the dating itself is as precise as it gets. That doesn't make birth more predictable: IVF babies, like all babies, arrive across a range of a few weeks around the due date.
How many weeks pregnant am I at transfer?
At a day 5 transfer you are considered 2 weeks and 5 days pregnant; at a day 3 transfer, 2 weeks 3 days. Your beta hCG test around 9–11 days after a day 5 transfer happens at roughly 4 weeks.