IVF Due Date Calculator
Calculate your IVF due date instantly. Day-3 transfer adds 263 days; Day-5 blastocyst adds 261 days. Get gestational age and key milestones.
See step-by-step calculation
When to use this calculator
- Calculating EDD after a fresh Day-3 or Day-5 embryo transfer
- Calculating EDD after a frozen embryo transfer (FET) with Day-3 or Day-5 embryos
- Tracking gestational age week-by-week after IVF
- Planning first trimester screening and anatomy scan appointments
- Sharing a reliable due date with your OB or midwife
- Comparing IVF due date with a natural-cycle estimate
IVF Due Date Offsets & Gestational Age Milestones
| Milestone / Transfer Type | Days Added to Transfer Date | Gestational Age (from LMP equiv.) | Days from LMP Equivalent |
|---|---|---|---|
| Day-5 blastocyst transfer → EDD | + 261 days | 40w 0d | 280 days |
| Day-3 embryo transfer → EDD | + 263 days | 40w 0d | 280 days |
| LMP equivalent (Day-5) | Transfer date − 19 days | 0w 0d | 0 days |
| LMP equivalent (Day-3) | Transfer date − 17 days | 0w 0d | 0 days |
| End of 1st Trimester | — | 12w 0d | 84 days |
| Anatomy Scan (mid-pregnancy) | — | 20w 0d | 140 days |
| Start of 3rd Trimester | — | 28w 0d | 196 days |
| Full Term begins | — | 39w 0d | 273 days |
| Estimated Due Date (EDD) | — | 40w 0d | 280 days |
Fuente: ACOG Committee Opinion 700 — Methods for Estimating the Due Date (American College of Obstetricians and Gynecologists, 2017). Frozen embryo transfers (FET) use the same offsets as fresh transfers; the freeze/thaw process does not affect gestational age calculation.
How it works
What is an IVF due date?
An IVF due date is the estimated delivery date calculated from the embryo transfer date plus the embryo's age in days. Day-5 blastocyst transfers add 261 days; Day-3 transfers add 263 days. This method provides more precise dating than natural conception because the exact fertilization timing is known.
How IVF Due Dates Are Calculated
In natural conception, gestational age is counted from the Last Menstrual Period (LMP), which is approximately 2 weeks before ovulation. A full-term pregnancy is 280 days (40 weeks) from LMP.
In IVF, the retrieval and fertilization dates are known. Embryo age at transfer is counted from the day of egg retrieval (Day 0). The formula back-calculates an equivalent LMP, then adds 280 days.
// Day-3 fresh transfer
LMP equivalent = Transfer Date − 3 days − 14 days = Transfer Date − 17 days
EDD = LMP equivalent + 280 days = Transfer Date + 263 days
// Day-5 blastocyst fresh transfer
LMP equivalent = Transfer Date − 5 days − 14 days = Transfer Date − 19 days
EDD = LMP equivalent + 280 days = Transfer Date + 261 daysFor frozen embryo transfers (FET), the embryo was already cultured to Day 3 or Day 5 before freezing, so the same offset applies. The transfer date is used identically — the freeze/thaw process does not add gestational age.
Gestational Age Milestones
Gestational age (GA) is always counted from the LMP equivalent:
| Milestone | GA | Days from LMP equiv |
|---|---|---|
| End of 1st Trimester | 12w 0d | 84 days |
| Anatomy Scan (mid-pregnancy) | 20w 0d | 140 days |
| Start of 3rd Trimester | 28w 0d | 196 days |
| Full Term begins | 39w 0d | 273 days |
| EDD | 40w 0d | 280 days |
Worked Example
Limitations
Frequently asked questions
Is IVF due date calculation more accurate than natural pregnancy?
Why does a Day-5 transfer use 261 days and Day-3 uses 263 days?
Does a frozen embryo transfer (FET) change the due date calculation?
What if my clinic transferred a Day-6 blastocyst?
My ultrasound due date differs from this calculator. Which one is correct?
Does a donor egg transfer use the donor's retrieval date?
When is the first trimester screening typically scheduled?
What does 'gestational age' mean for an IVF pregnancy?
Is this calculator suitable for ICSI, IUI, or natural IVF?
Sources & references
- ACOG Committee Opinion 700 — Methods for Estimating the Due Date — American College of Obstetricians and Gynecologists (2017)
- CDC Reproductive Health — Assisted Reproductive Technology — Centers for Disease Control and Prevention (2024)
- SART — Society for Assisted Reproductive Technology Patient Resources — Society for Assisted Reproductive Technology (2025)
- ASRM — Assisted Reproductive Technologies: A Guide for Patients — American Society for Reproductive Medicine (2024)
Methodology & trust
Calculadora de familia revisada por el equipo editorial de Hacé Cuentas, contrastada con ACOG Committee Opinion 700 — Methods for Estimating the Due Date, según nuestra política editorial y metodología.
Última revisión: June 20, 2026. Los parámetros se verifican periódicamente con las fuentes citadas.
Calculations run 100% in your browser. We do not store or transmit your data.
Indicative results. For critical decisions, consult a professional.
Rodríguez, M. (2026). IVF Due Date Calculator. Hacé Cuentas. https://hacecuentas.com/ivf-due-date-calculator
Contenido bajo licencia CC-BY 4.0 — reutilizable citando la fuente con enlace a Hacé Cuentas.