IVF Due Date Calculator
Use your embryo transfer date or egg retrieval date to estimate your due date and pregnancy milestones.
What this IVF due date calculator does
This IVF pregnancy calculator estimates your expected due date using dates specific to assisted reproduction. Unlike a standard pregnancy calculator that starts from the first day of your last menstrual period, IVF dating is usually more precise because the key treatment dates are known.
Whether you are using fresh transfer, frozen embryo transfer (FET), or calculating from egg retrieval, this tool gives a practical estimate for:
- Estimated due date (EDD)
- Estimated conception date
- Current gestational age in weeks and days
- Important trimester milestones
How to use the calculator
Option 1: Embryo transfer date (most common)
Enter the date your embryo was transferred and select the embryo age (for example day 5 blastocyst). The calculator applies the IVF due date formula and returns your estimated delivery date.
Option 2: Egg retrieval date
If you want a quick estimate from your retrieval cycle, enter your egg retrieval date. The calculator treats retrieval as the conception reference date and estimates due date accordingly.
IVF due date formula explained
From embryo transfer date
Due Date = Transfer Date + (266 - Embryo Age in days)
Example for a day 5 transfer: add 261 days to the transfer date.
From egg retrieval date
Due Date = Retrieval Date + 266 days
This follows the standard obstetric convention of about 38 weeks from conception to due date.
Day 3 vs day 5 embryo transfer and due date
The embryo age matters because implantation timing differs by transfer stage:
- Day 3 transfer: due date is typically 263 days after transfer.
- Day 5 transfer: due date is typically 261 days after transfer.
- Day 6 transfer: due date is typically 260 days after transfer.
These differences are small but clinically important for accurate week-by-week pregnancy tracking.
Why IVF dating is often more accurate
In spontaneous conception, ovulation and fertilization are estimated. In IVF, transfer and retrieval dates are known, which improves date precision early in pregnancy. Even so, ultrasound measurements can occasionally adjust estimated due date if fetal growth patterns suggest a better clinical timeline.
Frequently asked questions
Does frozen embryo transfer change due date calculation?
No. A frozen embryo transfer due date is calculated the same way as a fresh transfer. What matters is transfer date and embryo age.
Can this calculator predict the exact day of birth?
No calculator can predict exact delivery day. Most births occur within a window around the due date. Your clinician will interpret progress with your full medical context.
What if my ultrasound date is different?
Small differences can happen. Your fertility or obstetric team may keep IVF dating or adjust based on early ultrasound findings and practice guidelines.
Important note
This IVF due date calculator is for education and planning only. It is not medical advice and does not replace your reproductive endocrinologist or OB provider. Always follow your clinic's official dating, test schedule, and prenatal recommendations.