👶 IVF Due Date Calculator
Calculate your IVF due date from your embryo transfer date or egg retrieval date. Supports Day 3 and Day 5 transfers (fresh and frozen). Includes milestone timeline, trimester progress, and gestational age.
What Is an IVF Due Date Calculator?
An IVF due date calculator estimates your baby's expected delivery date after conceiving through In Vitro Fertilization (IVF). Unlike natural pregnancies — where the due date is calculated from the last menstrual period (LMP) — IVF due dates are calculated from the embryo transfer date or egg retrieval date.
Because the exact timing of fertilisation and embryo development is known in IVF, IVF due dates are generally more accurate than LMP-based estimates.
How Is the IVF Due Date Calculated?
The standard IVF due date formula is:
EDD = Transfer Date + (266 − Embryo Age)
where 266 days is the standard gestation period from conception, and Embryo Age is the number of days the embryo developed before transfer (3, 5, or 6 days).
This translates to simple formulas based on embryo stage:
- Day 3 Transfer: Transfer Date + 263 days (266 − 3)
- Day 5 Transfer: Transfer Date + 261 days (266 − 5)
- Day 6 Transfer: Transfer Date + 260 days (266 − 6)
- Egg Retrieval Date: Retrieval Date + 266 days
These formulas apply equally to fresh and frozen embryo transfers (FET), because the embryo's developmental age is what matters for dating.
Why Are IVF Due Dates More Accurate?
In natural pregnancies, the due date is estimated from the LMP, which assumes ovulation occurs on day 14 of a 28-day cycle. However, cycle lengths vary, and ovulation timing can be unpredictable.
In IVF, the exact date of fertilisation and the precise age of the embryo at transfer are known. This eliminates the uncertainty associated with ovulation timing, making the IVF due date more precise than LMP-based estimates.
Trimester Timeline
- First Trimester (Weeks 1–13): Embryonic development, major organ formation, highest risk of miscarriage.
- Second Trimester (Weeks 14–27): Fetal growth, movement felt (quickening), anatomy scan, viability threshold at 24 weeks.
- Third Trimester (Weeks 28–40+): Rapid weight gain, lung maturation, preparation for delivery.
Key IVF Milestones
- Beta hCG Test (9–14 days post-transfer): Blood test to confirm pregnancy.
- First Ultrasound (~6–7 weeks): Confirms intrauterine pregnancy and heartbeat.
- Graduation to OB (8–10 weeks): Transition from fertility clinic to regular prenatal care.
- NT Scan (11–14 weeks): First-trimester screening for chromosomal abnormalities.
- Anatomy Scan (18–22 weeks): Detailed ultrasound of fetal anatomy.
- Viability (24 weeks): Point at which the fetus may survive outside the womb with intensive care.
Why Use This Calculator?
- IVF-specific: Uses the correct formulas for Day 3, Day 5, and Day 6 transfers, plus egg retrieval dating.
- Instant results: Get your due date, gestational age, and trimester in seconds.
- Milestone timeline: Track key IVF pregnancy milestones and upcoming tests.
- Visual progress bar: See how far along you are at a glance.
- Free & private: No registration, no data storage — all calculations are done in your browser.
❓ IVF Due Date Calculator FAQ
How is the IVF due date calculated?
The IVF due date is calculated from the embryo transfer date using the formula: EDD = Transfer Date + (266 − Embryo Age). For a Day 5 transfer, this is Transfer + 261 days. For a Day 3 transfer, it is Transfer + 263 days.
What if I only know my egg retrieval date?
If you only know your egg retrieval date, add 266 days (38 weeks) to that date. This is because fertilisation typically occurs on the day of retrieval.
Does the embryo stage (Day 3 vs Day 5) affect the due date?
Yes. A Day 5 blastocyst transfer results in a due date that is 2 days later than a Day 3 transfer on the same date, because the embryo is 2 days older at transfer.
Is the due date for frozen embryo transfer (FET) different?
No. The due date calculation is the same for fresh and frozen transfers — it depends on the embryo's developmental age at transfer, not on whether it was frozen.
Why is the IVF due date more accurate?
IVF due dates are more accurate because the exact date of fertilisation and embryo development is known. In natural pregnancies, the due date relies on estimating ovulation from the LMP, which can be less precise.
What is the viability threshold?
Viability is generally considered to be around 24 weeks of gestation, though this can vary by hospital and country. Survival rates improve significantly after 28 weeks.
When is the first ultrasound after IVF?
The first ultrasound is typically scheduled 6–7 weeks after your last menstrual period (or about 4–5 weeks after transfer). This scan confirms the pregnancy is intrauterine and checks for a heartbeat.
How accurate is this calculator?
This calculator uses the standard IVF dating formulas accepted by fertility clinics worldwide. However, your doctor may adjust the due date after an ultrasound. Always consult your healthcare provider for medical advice.
What does "gestational age" mean in IVF?
Gestational age is measured from the first day of your last menstrual period (which is typically 2 weeks before conception). In IVF, gestational age is calculated by adding 14 days to the embryo age at transfer, then counting from the transfer date.
Is this calculator free?
Yes, this calculator is completely free to use. No registration or personal data storage is required.