Calculate your IVF pregnancy due date from your embryo transfer date. Supports fresh transfers, frozen embryo transfers (FET), Day 3, Day 5, Day 6 blastocysts, and egg donation cycles.
| Transfer Type | Days Added to Transfer Date | LMP Equivalent | Due Date Formula |
|---|---|---|---|
| Day 3 Fresh/Frozen | +269 days | Transfer − 17 days | Transfer + 263 days |
| Day 5 Fresh/Frozen ⭐ | +263 days | Transfer − 19 days | Transfer + 261 days |
| Day 6 Blastocyst | +262 days | Transfer − 20 days | Transfer + 260 days |
| Egg Donation D5 | +263 days | Based on recipient LMP | Transfer + 261 days |
⭐ Day 5 blastocyst transfer is the most common IVF transfer type with the highest success rate. These formulas are based on the standard IVF gestational dating protocol.
Unlike natural pregnancy where due date is calculated from your last menstrual period, IVF due dates are calculated from the embryo transfer date. The formula adjusts based on the age of the embryo at transfer. For a Day 5 blastocyst, you subtract 19 days from the transfer date to get the LMP equivalent, then add 280 days to that — which equals transfer date + 261 days.
For a frozen embryo transfer (FET), the calculation is the same as a fresh transfer of the same embryo age. The freezing process does not change the embryo's developmental age.
For Pakistani IVF patients: Major IVF clinics in Lahore, Karachi, and Islamabad typically confirm your due date via ultrasound at the 6–7 week scan (about 2–3 weeks after transfer). If your ultrasound date differs from this calculator by more than 5–7 days, your doctor will adjust your due date based on the scan measurement.