The Most Accurate IVF Due Date Calculator (2025)

Your IVF journey is unique, and so is your pregnancy timeline. Get a precise due date based on your specific transfer or retrieval date with our easy-to-use calculator.

Medically reviewed for accuracy | Updated on: August 28, 2025

IVF & FET Due Date Calculator

Calculate From: Egg Retrieval / IUI Date 3-Day Embryo Transfer Date 5-Day Embryo (Blastocyst) Transfer Date

Select the Date:

Your Estimated Due Date is:

You are approximately pregnant.

Your first trimester ends around .

Your second trimester ends around .

First and foremost, congratulations on reaching this incredible milestone. The journey through In Vitro Fertilization (IVF) is a testament to hope, science, and immense strength. Now that you're looking forward, one of the first questions on your mind is naturally, "When is my baby due?"

ivf due date calculator​

You've probably seen standard due date calculators online, but they're built for natural pregnancies, using the last menstrual period (LMP)—a date that's often irrelevant in the world of IVF. You need a tool built for your specific timeline. This page is more than just a calculator; it's a comprehensive guide to understanding your unique IVF pregnancy timeline.

How This IVF Calculator Works (And Why It's More Precise)

A standard pregnancy is estimated to last 40 weeks (280 days) from the first day of the last menstrual period (LMP). This method assumes ovulation happened around day 14. It's a great estimate, but it's still just an estimate.

IVF is different. It's a science of precision. We don't have to guess when conception happened; we know the *exact date*. Instead of LMP, our calculator uses the precise date of your IVF procedure to give a much more accurate due date.

• It uses a gestation period of 38 weeks (266 days) from the date of conception (egg retrieval).
• It then adjusts this date based on the age of the embryo at the time of transfer.

Understanding the Key IVF Dates: A Detailed Breakdown

To get the most accurate result, select the option in the calculator that matches your procedure.

Method 1: Egg Retrieval or IUI Date

This is considered "Day 0" of conception. It's the most accurate starting point. If you know this date, your due date is calculated simply as:
Formula: Date of Egg Retrieval + 266 Days

Method 2: 3-Day Embryo Transfer Date

At this stage, your embryo is in the "cleavage stage." Since the embryo was already 3 days old when it was transferred, we subtract those 3 days from the standard gestation period.
Formula: Date of 3-Day Transfer + 263 Days (266 - 3)

Method 3: 5-Day Embryo (Blastocyst) Transfer Date

A 5-day-old embryo is called a blastocyst. This is the most common type of transfer today. Because your embryo was already 5 days old, we adjust the calculation accordingly.
Formula: Date of 5-Day Transfer + 261 Days (266 - 5)

What About Frozen Embryo Transfer (FET)?

The process is exactly the same! For a frozen embryo transfer, you simply use the age of the embryo when it was frozen. If you transferred a frozen 5-day blastocyst, you would select the "5-Day Embryo Transfer" option and use the date of the transfer.

Is an IVF Due Date More Accurate Than a "Natural" One?

In a word: yes. Because we eliminate the guesswork around ovulation and conception dates, an IVF due date is generally considered more accurate. While only about 5% of all babies are born on their exact due date, your IVF due date provides a very reliable timeframe.

Your doctor will confirm this date with an early ultrasound, usually around 6-8 weeks. At this stage, they can measure the embryo (crown-rump length) to verify that its growth matches the expected gestational age. In most IVF cases, the ultrasound date and the calculated date align perfectly.

Your IVF Pregnancy Timeline: What Happens Next?

Getting your due date is the first exciting step. Here’s a brief look at what comes next:

• The Two-Week Wait: The period after transfer before your first pregnancy test (beta hCG blood test).
• First Ultrasound (6-8 Weeks): This is when you'll likely see the first flicker of a heartbeat and confirm the pregnancy is viable.
• End of First Trimester (around 13 weeks): A major milestone, as the risk of miscarriage drops significantly.
• Anatomy Scan (18-22 Weeks): A detailed ultrasound to check on your baby's development.
• End of Second Trimester (around 27 weeks): You're on the home stretch!

Frequently Asked Questions (FAQs)

Q1. Why don't doctors just use the transfer date and add 9 months?
Because pregnancy is clinically measured as 40 weeks, which is slightly more than 9 months. Using the precise 266-day gestation period from conception provides a much more accurate medical timeline for monitoring the baby's growth.

Q2. Can my IVF due date change?
It's very unlikely. Unlike a natural pregnancy where the due date might be adjusted based on an early ultrasound, an IVF due date is based on a known conception date and is almost always fixed.

Q3. How does this calculator work for twins?
The due date calculation is exactly the same for a single baby or multiples. However, it's important to know that twin pregnancies often deliver earlier than the 40-week due date, typically around 36-37 weeks.

Q4. What is a "due week"?
Many doctors now prefer to talk about a "due week" (the week your due date falls in) rather than a single day. This helps manage expectations, as it's perfectly normal for a baby to arrive any time between 38 and 41 weeks.

Wishing You a Healthy and Happy Journey

We know that every step of the IVF process is filled with anticipation. Calculating your due date is a beautiful moment to celebrate and look forward to the future. We hope this tool and guide have brought you clarity and excitement. Wishing you all the very best on the incredible journey ahead!