IVF Due Date Calculator
Calculate your due date after IVF or FET. Estimate delivery date based on egg retrieval, embryo transfer, or embryo age with trimester milestones and key pregnancy dates.
Calculate Due Date From:
Related Calculators
About This Calculator
Calculating your due date after IVF (In Vitro Fertilization) is different from natural conception because you know the exact date of fertilization or embryo transfer. This precision makes IVF due dates among the most accurate available. This calculator helps you determine your estimated due date based on your transfer or retrieval date.
Why IVF Due Dates Are More Accurate: With natural conception, the exact fertilization date is unknown, so due dates are estimated from the last menstrual period (LMP). IVF removes this uncertainty because you know precisely when fertilization occurred (egg retrieval) or when the embryo was transferred.
How IVF Due Dates Are Calculated:
- From Egg Retrieval: Day 0 = retrieval date. Due date = retrieval + 266 days
- From Transfer: Subtract embryo age, then add 266 days
- Day 5 Blastocyst Transfer: Transfer date + 261 days (266 - 5)
- Day 3 Cleavage Transfer: Transfer date + 263 days (266 - 3)
Fresh vs. Frozen Transfers: The calculation is the same whether you had a fresh transfer or a frozen embryo transfer (FET). What matters is the embryo age at the time of transfer.
Medical Disclaimer: This calculator provides estimates for educational purposes. Your fertility clinic will provide official due date calculations. Only about 5% of babies arrive on their exact due date - most arrive within 2 weeks before or after.
For standard pregnancy due dates, see our Pregnancy Due Date Calculator. For tracking pregnancy progress, try our Pregnancy Week Calculator.
How to Use the IVF Due Date Calculator
- 1Select whether to calculate from transfer date or egg retrieval date.
- 2Enter the date of your embryo transfer or egg retrieval.
- 3If using transfer date, select the embryo age (Day 3, 5, or 6).
- 4Review your estimated due date.
- 5Check your current gestational age if already pregnant.
- 6View key pregnancy milestones and their dates.
- 7Note the full-term delivery range (37-42 weeks).
- 8Compare with dates provided by your fertility clinic.
- 9Track your progress through each trimester.
- 10Discuss any discrepancies with your healthcare provider.
Understanding IVF Due Date Calculations
How due dates are determined after IVF.
The Basic Formula
A full-term pregnancy is 280 days (40 weeks) from LMP or 266 days (38 weeks) from conception/fertilization.
From Egg Retrieval (Day 0): Due Date = Retrieval Date + 266 days
From Embryo Transfer: Due Date = Transfer Date + (266 - Embryo Age in days)
Embryo Age Explained
| Transfer Type | Embryo Age | Days to Add |
|---|---|---|
| Day 3 (Cleavage) | 3 days old | 263 days |
| Day 5 (Blastocyst) | 5 days old | 261 days |
| Day 6 (Blastocyst) | 6 days old | 260 days |
Example Calculation
Day 5 Blastocyst Transfer on January 15:
- Embryo is already 5 days old at transfer
- Equivalent conception date: January 10 (Jan 15 - 5 days)
- Due date: January 10 + 266 days = October 3
Or simply: January 15 + 261 days = October 3
Equivalent LMP
Doctors often track pregnancy from "LMP" even for IVF: Equivalent LMP = Conception Date - 14 days
This allows standard pregnancy tracking and ultrasound dating.
Fresh vs. Frozen Embryo Transfer
Understanding timing for different IVF protocols.
Fresh Embryo Transfer
Embryo is transferred in the same cycle as egg retrieval.
Timeline:
- Day 0: Egg retrieval
- Day 0-1: Fertilization
- Day 3: Cleavage stage transfer (if chosen)
- Day 5-6: Blastocyst transfer (most common)
Due Date: Calculated from either retrieval or transfer date.
Frozen Embryo Transfer (FET)
Embryo is frozen after fertilization and transferred in a later cycle.
Key Point: Embryo age is determined at the time of freezing. A Day 5 embryo that was frozen is still Day 5 when transferred, regardless of how long it was frozen.
Due Date Calculation: Same as fresh transfer - based on embryo age at transfer.
Why FET Due Dates Are Identical
Whether frozen for 1 month or 5 years:
- A Day 5 blastocyst transferred on January 15 = October 3 due date
- Freezing pauses embryo development
Fresh vs. FET Outcomes
Modern studies show FET may have:
- Slightly higher success rates
- Lower risk of preterm birth
- Similar due date accuracy
Your fertility specialist will recommend the best protocol for your situation.
Why IVF Due Dates Are More Accurate
The precision advantage of assisted reproduction.
Natural Conception Uncertainty
With natural conception:
- Ovulation can vary by days
- Sperm can survive 3-5 days
- Actual conception date is estimated
- LMP-based calculations assume 28-day cycles
Accuracy: ±2 weeks typical error
IVF Precision
With IVF:
- Egg retrieval date is known exactly
- Fertilization happens within 24 hours
- Embryo age at transfer is documented
- No cycle variation affects calculation
Accuracy: ±1-2 days potential error
Clinical Implications
Ultrasound dating:
- First-trimester ultrasounds confirm IVF due dates
- Usually within 3-5 days of calculated date
- Less need for date adjustments
Delivery planning:
- More accurate timing for monitoring
- Better prediction of full-term window
- Clearer communication with OB team
When Dates May Be Adjusted
Even with IVF, due dates may be modified based on:
- Crown-rump length measurements at 8-12 weeks
- Multiple pregnancy timing
- Baby's growth patterns
- Clinical judgment
Always follow your healthcare provider's dating.
Pregnancy Milestones After IVF
Key dates and events during your IVF pregnancy.
First Trimester (Weeks 1-13)
| Week | Milestone |
|---|---|
| 4-5 | First positive pregnancy test possible |
| 5-6 | Gestational sac visible on ultrasound |
| 6-7 | Heartbeat may be detected |
| 8 | First prenatal appointment |
| 10-12 | NIPT/genetic testing option |
| 12-13 | End of first trimester |
IVF Specific: Beta HCG blood tests typically at 10-14 days post-transfer.
Second Trimester (Weeks 14-27)
| Week | Milestone |
|---|---|
| 16-18 | Anatomy scan scheduled |
| 18-22 | Detailed anatomy ultrasound |
| 20 | Halfway point |
| 24 | Viability threshold |
| 24-28 | Glucose screening |
Third Trimester (Weeks 28-40)
| Week | Milestone |
|---|---|
| 28 | Third trimester begins |
| 32 | Growth scan may be done |
| 36 | Group B strep test |
| 37 | Full term begins |
| 39 | Ideal delivery window begins |
| 40 | Due date |
| 41 | Post-dates discussion |
IVF-Specific Considerations
- May have more frequent monitoring
- Possible early discharge from RE to OB
- May need to share IVF records with OB
- Genetic testing results may already be known (if PGT was done)
Twins and Multiple Pregnancies
Due date considerations for IVF multiples.
Higher Multiple Rate in IVF
IVF has higher rates of twins due to:
- Multiple embryo transfers (less common now)
- Higher rate of identical splitting
Note: Many clinics now recommend single embryo transfer (SET) to reduce twin risks.
Due Date Adjustments for Twins
Twins are considered full-term earlier:
- Full term: 37-38 weeks (not 40)
- Most deliver: 36-37 weeks
- Target: Delivery before 38 weeks
Adjusted Due Date: If singleton due date = October 3 Twin "goal" date = ~September 12-19 (2-3 weeks earlier)
Monitoring Differences
Twin pregnancies require:
- More frequent ultrasounds
- Earlier and more growth monitoring
- Careful attention to complications
- Possible earlier delivery planning
Calculating for Triplets or More
Higher-order multiples deliver even earlier:
- Triplets: ~32-34 weeks average
- Individual due date calculation unchanged
- Expected delivery window very different
Important: Multiple pregnancies from IVF require specialized care. Your maternal-fetal medicine specialist will provide specific guidelines.
Due Date Accuracy and Expectations
What to realistically expect from your due date.
The "Due Date" Reality
- Only 5% of babies arrive on their exact due date
- 80% arrive within 2 weeks before or after
- "Due month" is more realistic than "due date"
Full-Term Range
| Week | Status |
|---|---|
| Before 37 | Preterm |
| 37-38 | Early term |
| 39-40 | Full term |
| 41 | Late term |
| After 42 | Post-term |
Goal: Delivery at 39+ weeks when possible.
IVF Delivery Statistics
Research shows IVF babies:
- Average delivery: ~39 weeks
- Slightly higher preterm rate than natural conception
- Due to maternal age factors, not IVF itself
Factors That May Affect Delivery Date
Earlier delivery more likely with:
- Multiple pregnancy
- Pregnancy complications
- Maternal health conditions
- Prior preterm birth
Later delivery possible with:
- First pregnancy
- Later maternal age (sometimes)
- No complications
Induction Considerations
Many OBs discuss induction options:
- At 39 weeks for certain conditions
- At 41 weeks if no labor starts
- Based on individual circumstances
Your provider will discuss the best timing for you.
Pro Tips
- 💡Keep records of your transfer date and embryo age for accurate calculations.
- 💡Provide your fertility clinic records to your OB for seamless care transition.
- 💡Use your IVF "equivalent LMP" date when asked about last period by providers.
- 💡First-trimester ultrasound will confirm your due date with high accuracy.
- 💡Remember the due date is an estimate - plan for a 4-week delivery window.
- 💡IVF pregnancies are monitored the same as natural pregnancies after the first trimester.
- 💡Ask your RE when you'll "graduate" to regular OB care (typically 8-12 weeks).
- 💡Multiple pregnancy due dates differ - twins arrive earlier on average.
- 💡Stay in touch with your fertility team for any early pregnancy concerns.
- 💡Consider your due date a "due month" for more realistic expectations.
- 💡Track pregnancy milestones to celebrate progress along the way.
- 💡Discuss birth planning with your OB starting around 32-34 weeks.
Frequently Asked Questions
IVF due dates are more accurate because you know the exact date of fertilization (egg retrieval day) or embryo transfer. Natural conception due dates are estimated from last menstrual period with ±2 weeks uncertainty. IVF calculations use the precise day of fertilization plus 266 days.
