How to Calculate Due Date From Embryo Transfer Date

Quick Answer

You can calculate your estimated due date after an embryo transfer cycle by adding 263 days to your transfer date if it was a day 3 (cleavage stage) transfer and 261 days if it was a day 5 (blastocyst stage) transfer. The same is true whether you are using fresh or frozen embryos.

If you’re planning on doing an embryo transfer (whether a fresh embryo transfer following an IVF cycle or a frozen embryo transfer at a later time), this article will help you understand the math behind estimating your due date and why embryo age affects your answer.

Embryo Age Explained

Embryo age refers to how long an embryo develops before transfer. Most clinics transfer embryos that have developed for 5 days and are in the blastocyst stage. Day 3 embryos, which are developed to the cleavage stage, are less commonly used. Your physician will recommend one or the other based on the specifics of your care.

Your care team will personalize your care plan based on your health history and goals to optimize your chances of success.

What You Need to Know About Calculating Due Date From Embryo Transfer Date

In order to calculate your due date after an embryo transfer, you start with how many days after fertilization the transfer of the embryo took place.

If you had a day 3 transfer: Add 263 days to your transfer date. For example, if your embryo transfer date was June 15th, your estimated due date would be 263 days later on March 5th.

If you had a day 5 transfer: Add 261 days to your transfer date. For example, if your embryo  transfer date was June 15th, your estimated due date would be 261 days later on March 3rd.

Why 261 or 263 days? A typical term of pregnancy is 40 weeks after the first day of the last menstrual period. In a spontaneous menstrual cycle, conception typically happens roughly 2 weeks after the last period and 38 weeks (or 266 days) before the estimated due date. Because we are transferring an embryo that has already developed for a period of time during an IVF cycle, there are fewer days between transfer and estimated due date.

Why This Matters for Patients

Your fertility clinic will give you an estimated due date for your embryo transfer cycle, so you don’t have to worry about calculating it on your own. Still, having the ability to do it for yourself if you don’t remember between visits or just so you can understand the calculation can help you feel more informed about the process.

What Affects Your Estimated Due Date

The only factor that impacts your estimated due date after an embryo transfer is the number of days between egg retrieval/fertilization and the transfer. Most of the time, the transfer happens 5 days after fertilization.

Whether you’re using fresh or frozen embryos for the transfer does not matter in terms of estimating the due date. The frozen embryo will be thawed and transferred the morning of the scheduled embryo transfer.

FAQs

How can you calculate your due date after intrauterine insemination (IUI)?

The process for calculating your estimated due date after IUI is the same as it is for calculating your due date after conceiving without fertility treatment. You would add 266 days to the date of insemination. For example, if insemination happened on June 15th, your estimated due date would be 266 days later on March 6th.

How are pregnancies dated?

Typically, pregnancies are dated based on the first day of your last menstrual period, sometimes called “LMP”. This is easier to calculate in spontaneous menstrual cycles where the LMP date is known. In fertility treatment, we calculate your LMP based on the date of ovulation or the date of your embryo transfer. 

What happens in an embryo transfer?

After the retrieved eggs are fertilized and develop into blastocysts, your healthcare team will work with you to decide which embryo to transfer.

The steps of the embryo transfer process:

1. Your provider will inspect your cervix with a speculum and clean it.
2. Your provider will insert a catheter through your cervix to reach the uterus.
3. Your provider will insert the embryo or embryos using another catheter.
4. If the procedure is successful, the embryo or embryos will implant within a few days.
5. You will take a pregnancy blood test 10-12 days after the transfer.

Early Pregnancy Care at San Diego Fertility Center

After a successful IVF cycle, we provide prenatal care and monitor our patients’ pregnancies for about 10 weeks. Once it’s been 10 weeks, San Diego Fertility Center will transfer your care and pregnancy monitoring to your chosen OB/GYN.

If your test doesn't come back positive after an embryo transfer, we will schedule a follow-up consultation to discuss your next steps. We are here to support you through this process and explore every avenue available for achieving your pregnancy goals.

Next Steps for Patients at San Diego Fertility Center

Whatever your goals are for building your family, we are here to help you understand your options, your likelihood of success with IVF, and what to expect throughout the process. We’ll work together to create a plan that’s right for you.

Schedule your consultation today at San Diego Fertility Center.

Clinically reviewed by Emily Gray, RN