IVF Due Date Calculator

Calculate your due date from embryo transfer date. Compare transfer types, view milestone timeline, and track gestational age with precision IVF dating.

Transfer Details
TRIMESTER PROGRESS
Results
Estimated Due Date
Gestational Age
Trimester
Days to Due
Days Pregnant
Weeks Remaining
Full Term (39w)
T1 (wks 1–13)T2 (14–27)T3 (28–40)
5-day: Due = Transfer + 261 d
3-day: Due = Transfer + 263 d
6-day FET: Due = Transfer + 260 d
vs. Natural Conception (LMP Method)

Transfer Type Comparison

Side-by-side comparison of due dates for all transfer types from the same date. Adjust the date in Tab 1 to update.

Gestational Age at Current Date by Transfer Type

IVF Success Rates by Age

AgeFresh embryo (own eggs)Donor eggs
<3545–50%55–65%
35–3732–38%55–65%
38–4020–25%55–65%
41–4210–15%55–65%
43–445–8%55–65%
45+<3–5%55–65%

IVF Pregnancy Milestone Timeline

Key milestones from transfer to delivery, with estimated dates based on your inputs.

Milestone Timeline (weeks from transfer)

How to Use This Calculator

1
Select transfer type — Choose fresh 3-day, fresh 5-day (blastocyst), frozen 5-day, or frozen 6-day. Each type uses a different formula based on embryo age at transfer.
2
Enter your transfer date — Use the exact date from your clinic. The calculator instantly computes your due date, gestational age, and trimester progress.
3
Compare & explore — Use the Transfer Comparison tab to see how different transfer types affect your due date. The Milestone Timeline tab shows key IVF pregnancy events with estimated dates.

IVF Dating Formulas

5-day blastocyst: Due = Transfer + 261 days
3-day embryo: Due = Transfer + 263 days
6-day FET: Due = Transfer + 260 days
GA (weeks) = (Today - Transfer + embryo age + 14) / 7

Key Terms

Blastocyst — A 5–6 day old embryo that has developed to the blastocyst stage before transfer — higher implantation rate than 3-day embryos.
Gestational Age (GA) — Age of pregnancy in weeks/days; in IVF this is calculated from egg retrieval or transfer date, not LMP.
FET — Frozen Embryo Transfer; embryos frozen after a retrieval cycle and transferred in a subsequent cycle.
Beta hCG — Pregnancy hormone measured 9–14 days after transfer; first confirmation of implantation.
LMP Method — Natural conception dating from last menstrual period; IVF bypasses this with precise embryo dating.
NT Scan — Nuchal Translucency scan at 11–14 weeks; first trimester screening for chromosomal anomalies.
dp5dt / dp3dt — Days post 5-day transfer / 3-day transfer. Common shorthand for tracking early IVF milestones.
Viability Threshold — Around 24 weeks GA, when a fetus has a chance of survival with NICU support if delivered prematurely.

IVF Due Date vs Natural Conception Dating

IVF due dates differ from natural conception due dates because the embryo's exact age is known precisely. In natural conception, due dates are calculated by adding 280 days to the last menstrual period (LMP) — this assumes ovulation at day 14 of a 28-day cycle. IVF eliminates this uncertainty.

Why IVF Dating is Different

In a fresh 5-day blastocyst transfer, the embryo is already 5 days old at the time of transfer. To find the due date, we add 261 days (not 280) because 5 days of development plus 14 days of the theoretical pre-ovulation phase are already accounted for. For a 3-day embryo transfer, we add 263 days. A frozen 6-day blastocyst adds 260 days, since the embryo is one day older than a day-5.

Understanding Trimester Boundaries

The first trimester runs from conception through week 13 and 6 days. The second trimester covers weeks 14 through 27 (6 days). The third trimester runs from week 28 to delivery. Key screening tests are timed to trimester: NT scan in first trimester, anatomy scan (level II ultrasound) at 18–20 weeks in the second trimester.

Multiple Pregnancy Considerations

IVF pregnancies have a higher rate of multiples (twins, triplets) due to multiple embryo transfers. Multiple pregnancies typically deliver earlier than singletons — twins at 36–37 weeks, triplets at 32–34 weeks. Your OB will adjust the monitoring schedule accordingly if carrying multiples.

Frequently Asked Questions

How is an IVF due date different from a natural pregnancy?

IVF due dates use precise embryo age rather than LMP estimation. A 5-day blastocyst transfer adds 261 days; natural conception adds 280 days from LMP. IVF dating is generally more accurate because embryo age is known exactly.

Does it matter if my transfer was fresh or frozen?

The fresh vs frozen distinction matters for timing relative to retrieval, but not for the due date calculation itself. Both use the same formula based on embryo age at transfer. Frozen embryo outcomes are now comparable to fresh in most clinics.

What is the difference between a Day 5 and Day 6 blastocyst?

A Day 6 blastocyst took one extra day to reach full blastocyst stage. The due date shifts by one day (260 vs 261 days added). Success rates are slightly lower for Day 6, but many result in healthy pregnancies.

When will I have my first ultrasound?

Most IVF clinics schedule the first viability ultrasound at 6–7 weeks gestational age (approximately 3–4 weeks after a 5-day transfer). This confirms a heartbeat and intrauterine location.

What is beta hCG and when is it tested?

Beta hCG is the pregnancy hormone produced after implantation. Your clinic will typically test at 9–14 days after transfer. A positive beta (above 25 mIU/mL) confirms implantation. Doubling time (every 48–72 hours) is monitored in early pregnancy.

Can the due date change after an ultrasound?

An early ultrasound may revise the due date slightly based on embryo size. However, for IVF pregnancies where the transfer date is precisely known, ultrasound measurements usually confirm rather than change the due date.

What week is full term in pregnancy?

Full term is defined as 39–40 weeks. Early term is 37–38 weeks 6 days. Late term is 41 weeks 0–6 days. Post-term is 42 weeks or beyond. Most OBs plan delivery by 41 weeks.

What's the difference between 3-day and 5-day embryo transfers?

A 3-day embryo is at the cleavage stage (6–8 cells). A 5-day blastocyst has more cells and a cavity. Blastocyst transfers generally have higher implantation rates per embryo but not all embryos survive to day 5.

What prenatal tests should I expect in the first trimester?

First trimester screening typically includes: NT (nuchal translucency) ultrasound at 11–14 weeks, cell-free fetal DNA (NIPT) testing at 10+ weeks, and blood tests for PAPP-A and free beta-hCG.

When is the anatomy scan done?

The anatomy scan (Level II ultrasound) is performed at 18–20 weeks gestational age. It checks for structural abnormalities in the baby's organs, brain, spine, and limbs.

Is progesterone supplementation necessary after transfer?

Yes, progesterone support is standard after embryo transfer (typically vaginal suppositories, injections, or oral progesterone) until 8–10 weeks gestational age when the placenta takes over hormone production.

What if I'm carrying twins from IVF?

Twin pregnancies are monitored more closely and typically deliver earlier (average 35–36 weeks). The due date here refers to 40 weeks (singleton standard), but your OB will likely plan for 37–38 weeks delivery for twins.