IVF Due Date Calculator — Embryo Transfer or Egg Retrieval

Calculate Your IVF Due Date

Use the calculator above to get your personalised IVF estimated due date (EDD), current gestational age, recommended beta hCG test dates, first ultrasound timing, and full trimester breakdown — all calculated from your embryo transfer date or egg retrieval date.

How to Use This Calculator

1. Choose your calculation method. Select "By embryo transfer date" if you know the date your embryo was transferred. Select "By egg retrieval date" if you prefer to calculate from the point of fertilisation (day 0).
2. Enter your date. Type or pick your embryo transfer date or egg retrieval date. The date must be in the past and within the last 280 days.
3. Select embryo age at transfer (transfer method only). Choose Day 3 cleavage stage, Day 5 blastocyst (most common), or Day 6 blastocyst. This is recorded in your embryology report or clinic paperwork.
4. Select transfer type. Choose Fresh transfer or Frozen embryo transfer (FET). This does not change your due date but adjusts the beta hCG test date note in your results.
5. Click Calculate Due Date. Your estimated due date, gestational age, trimester, beta hCG test window, first ultrasound date, and trimester milestones will appear below the form.

Examples

How IVF Due Dates Are Calculated

IVF due date calculation uses the same 280-day gestational period as natural conception, but with a more precise starting point. Instead of estimating from a last menstrual period (LMP), IVF uses the embryo's exact developmental age to work backward to an equivalent LMP (eLMP) — and then adds 280 days from that anchor.

Why IVF Dating Is Different from Natural Conception

In natural conception, due dates are estimated as 280 days from the first day of the last menstrual period. This relies on a 28-day cycle and ovulation on day 14 — assumptions that introduce several days of uncertainty for many women.

In IVF, the fertilisation date is known precisely: egg retrieval is day 0. The embryo's age at transfer is documented in the embryology report. This means the equivalent LMP can be calculated exactly, making IVF due dates more reliable than LMP-based estimates from the outset.

The core formula: Due date = Retrieval date + 266 days (266 days = average time from fertilisation to birth). Or equivalently, for a transfer-based calculation: Due date = Transfer date + (266 − embryo age in days).

Day 3 vs Day 5 vs Day 6 Transfers

The embryo's age in days at the time of transfer directly determines the due date formula. All three calculations use the same underlying logic: subtract the embryo's lab age from 266 days.

Day 5 blastocyst transfers are the most common in modern IVF because extended culture to the blastocyst stage allows better embryo selection and higher implantation rates. Day 3 transfers are still used when a patient has few embryos or when blastocyst culture is not indicated. Day 6 blastocysts developed slightly more slowly in the lab but are still viable.

If you are unsure which day your embryo was transferred, check your embryology report, your clinic's discharge summary, or your embryo transfer consent form — the day is always recorded.

Fresh Transfer vs Frozen Embryo Transfer (FET)

For due date calculation, fresh and frozen transfers use the exact same formula. The freezing period does not count toward gestational age. A Day 5 FET uses Transfer date + 261 days, identical to a fresh Day 5 transfer.

What differs between fresh and frozen is the clinical protocol, not the math:

• Fresh transfer occurs 3–6 days after egg retrieval, within the same stimulation cycle. The uterus has been prepared by the body's natural response to ovarian stimulation.
• Frozen embryo transfer (FET) occurs in a separate cycle — natural, medicated, or programmed — after the embryo has been vitrified and stored. A medicated FET uses oestrogen and progesterone to prepare the uterine lining before transfer.

Whether your FET used a natural cycle or a fully medicated (artificial) cycle has no effect on the due date formula. Always confirm your due date with your reproductive endocrinologist, as some clinics use slightly different internal protocols.

Trimesters, Milestones & Test Dates

After a positive beta hCG, the IVF pregnancy follows the same gestational timeline as any pregnancy — but the early weeks involve more clinic contact than a naturally conceived pregnancy. Here is what to expect.

Recommended Beta hCG Test Dates

The beta hCG blood test — commonly called "the beta" — is the first official pregnancy confirmation in an IVF cycle. Your clinic will schedule it approximately 9–14 days after embryo transfer (or egg retrieval, if calculating from retrieval date). The exact day depends on your clinic's protocol; most schedule it at day 10–12 post-transfer for a Day 5 blastocyst.

A single beta value confirms whether hCG is present. A second test 48 hours later confirms the doubling time, which is the key indicator of a healthy early pregnancy. In viable IVF pregnancies, hCG typically doubles every 48–72 hours in the first weeks. At the beta test around 4 weeks gestational age, values can range from 10 to over 500 mIU/mL — a wide normal range. Your clinic interprets your values in clinical context.

Home urine tests may also turn positive 9–12 days after a Day 5 transfer, but the blood beta is more sensitive and is the clinical standard. Do not rely on a negative home test before your scheduled beta date.

First Ultrasound After IVF

Most IVF clinics schedule the first ultrasound at 6–7 weeks gestational age — approximately 4–5 weeks after a Day 5 blastocyst transfer. For a Day 3 transfer, this is around 5–6 weeks after transfer. For egg retrieval-based calculations, the first scan is typically 5–6 weeks after retrieval.

This scan has two primary goals:

• Confirm intrauterine pregnancy. Verifies the embryo has implanted in the uterus and not in the fallopian tube (ectopic pregnancy).
• Confirm cardiac activity. A heartbeat is typically visible from approximately 6 weeks gestational age. If no heartbeat is seen at 6 weeks, the scan is usually repeated in 1–2 weeks before any conclusions are drawn.

A second scan around 8–10 weeks gestational age is common before your IVF clinic graduates you to your OB-GYN. At this scan the crown-rump length (CRL) is measured to confirm gestational age. If CRL measurements differ from your transfer-based due date by more than 5–7 days, your provider may adjust the EDD slightly — this is normal and does not indicate a problem.

IVF Pregnancy Milestones Timeline

The gestational timeline below uses a Day 5 blastocyst transfer as the reference point. Adjust by ±1–2 days for Day 3 or Day 6 transfers.

• Transfer day (gestational week ~2+5): Embryo placed in the uterus. Implantation typically occurs over the next 1–3 days.
• 5–7 days post-transfer (week ~3+3 to ~3+5): Implantation usually complete. hCG begins to rise from the trophoblast cells.
• 9–14 days post-transfer (week ~4+0 to ~4+5): Beta hCG blood test — first official pregnancy confirmation in IVF.
• ~6 weeks gestational age (~4 weeks post Day 5 transfer): First ultrasound. Heartbeat visible if present. Confirms intrauterine pregnancy.
• ~8–10 weeks gestational age: Second ultrasound; CRL measurement. Most IVF clinics graduate patients to their OB-GYN at this point.
• 11–13 weeks (end of first trimester): NT scan (nuchal translucency) and first-trimester screening. Often the first appointment with your OB after graduation.
• 18–20 weeks: Anatomy scan (mid-pregnancy ultrasound). Checks fetal development and placental position.
• 28 weeks: Third trimester begins. Increased appointment frequency begins in most OB practices.
• 36–40 weeks: Cervical checks and delivery planning. Your EDD falls at 40 weeks gestational age.

The two-week wait (2WW) — the period between embryo transfer and the beta hCG test — is one of the most emotionally challenging parts of IVF. Progesterone supplementation, which most patients take after transfer, can mimic early pregnancy symptoms (breast tenderness, bloating, fatigue, nausea), making symptom-reading during this period unreliable.

Frequently Asked Questions (IVF-Specific)

Looking for answers to IVF due date questions? Our IVF-specific FAQ is below.

• How accurate is the IVF due date compared to natural conception?

  IVF due dates are generally more accurate than natural-conception dates because fertilisation is precisely known — either from the egg retrieval date (day 0) or the embryo's documented developmental stage at transfer. Natural conception due dates rely on estimated LMP and assumed ovulation on day 14, introducing several days of uncertainty. Your IVF clinic's transfer-based calculation is typically more reliable than any LMP estimate your OB might apply.

• Why is the IVF due date calculation different from natural conception?

  Standard pregnancy due dates are 280 days from the last menstrual period (LMP), which assumes ovulation on day 14. In IVF, fertilisation is precisely known: egg retrieval is day 0, and the embryo's age at transfer is documented. The IVF formula — retrieval date + 266 days, or transfer date + (266 minus embryo age) — eliminates the LMP estimation step entirely, making the due date more precise from the start.

• What does "5dp5dt" mean?

  "5dp5dt" stands for 5 days post Day-5 transfer — meaning 5 days after a Day 5 blastocyst embryo transfer. At 5dp5dt, you are approximately 6 weeks and 3 days gestational age (the Day 5 blastocyst corresponds to gestational day 19 from eLMP, plus 5 more days post-transfer). This shorthand is widely used in IVF communities and clinic communications, especially during the two-week wait.

• When will I have my first ultrasound after IVF?

  Most IVF clinics schedule the first ultrasound at 6–7 weeks gestational age — approximately 4–5 weeks after a Day 5 blastocyst transfer. This scan confirms a heartbeat (cardiac activity) and that the pregnancy is intrauterine, not ectopic. A second scan around 8–10 weeks is typical before graduating to your OB-GYN.

• What is the difference between fresh and frozen transfer for due date calculation?

  For due date calculation, there is no difference — the formula depends only on the embryo's developmental age (Day 3, 5, or 6) at transfer, not whether it was fresh or previously frozen. The freezing period does not count toward gestational age. A Day 5 FET uses Transfer date + 261 days, identical to a fresh Day 5 transfer. What differs is the cycle preparation protocol, not the math.

• Can my IVF due date change after the first ultrasound?

  Yes, it can shift slightly. At the 6–7 week scan, the sonographer measures crown-rump length (CRL) to confirm gestational age. If CRL differs from the transfer-based calculation by more than 5–7 days, your provider may adjust the due date. Discrepancies of 1–3 days are common and normal. The transfer-based date is the most reliable starting point; ultrasound adjustments are minor refinements, not corrections.

• How is gestational age calculated for IVF pregnancies?

  Gestational age in IVF is calculated from an equivalent LMP (eLMP) date, derived by subtracting the embryo's pre-transfer lab age plus 14 days from the transfer date. For a Day 5 blastocyst: eLMP = transfer date minus 19 days. For egg retrieval: eLMP = retrieval date minus 14 days. Gestational age is then counted as weeks and days since eLMP — exactly the same as natural conception, just with a more precise anchor point.

• What hCG level should I have at my beta test after IVF?

  A single beta hCG value is less important than the trend. At a typical beta test 9–12 days after a Day 5 transfer (~4 weeks gestational age), values in viable pregnancies range widely from 10 to over 500 mIU/mL. What matters most is the doubling time: hCG should double approximately every 48 hours in early pregnancy. Your clinic will order a repeat beta 48 hours after the first to confirm appropriate rise. Absolute numbers vary significantly between individuals and clinics.