IVF Embryo Transfers: The Complete Guide

Embryo transfers are one of the most critical steps in the in vitro fertilization (IVF) process. For intended parents—especially those working with a surrogate—understanding how embryo transfers work can make the journey to parenthood feel a little less overwhelming.

This guide breaks everything down: from what an embryo transfer is, to the differences between fresh and frozen transfers, to how success rates stack up. No fluff, no filler—just the facts you need.

What Is an Embryo Transfer?

An embryo transfer is the process of placing an embryo into the uterus, typically as the final step of an IVF cycle. It can happen in a gestational surrogate or in the intended mother's uterus, depending on the arrangement.

The embryo itself is created in a lab using eggs and sperm from the intended parents or donors. Once fertilization happens, the embryo is cultured for a few days before transfer.

Why Intended Parents Turn to Embryo Transfers

There are many reasons why intended parents may go through embryo transfer:

1. Infertility due to medical issues or age
2. Same-sex couples or single parents needing a surrogate
3. Genetic conditions that require embryo screening
4. Families growing through egg or sperm donation

In all cases, embryo transfer is the bridge between lab fertilization and real pregnancy.

Types of Embryo Transfers

Frozen Embryo Transfers (FETs)

Frozen embryo transfers involve using embryos that have been cryopreserved (frozen) from an earlier IVF cycle. These embryos are thawed and transferred during a separate cycle—often weeks or months later.

Why use FETs?

• Allows time for genetic testing (PGT-A or PGT-M)
• Flexible scheduling for surrogate and intended parents
• Lower risk of complications tied to ovarian stimulation

FETs are now more common than fresh transfers and offer excellent success rates, especially when embryos are frozen at the blastocyst stage.

Fresh Embryo Transfers (ETs)

Fresh embryo transfers happen within the same cycle as egg retrieval and fertilization. The embryo is transferred a few days after fertilization—no freezing involved.

Why use fresh transfers?

• Can be faster if timing is critical
• Avoids freezing and thawing process

However, fresh transfers may pose challenges if the uterine lining is not ready, or if hormone levels from stimulation are too high.

Day 3 Embryo Transfer

In a Day 3 transfer, the embryo is moved into the uterus three days after fertilization. At this stage, the embryo has typically reached the 6–8 cell stage.

Day 3 transfers are less common today, but still used when embryo development is slower or when lab conditions favor earlier transfer.

Day 5 Embryo Transfer

A Day 5 embryo is called a blastocyst. This embryo has more cells, is more developed, and often has a better chance of implantation.

Day 5 transfers are standard in most modern IVF clinics. Embryos that reach this stage tend to be stronger, and labs can select those with the highest potential.

Multiple vs. Single Embryo Transfer

In the early days of IVF, transferring multiple embryos was common. The goal: increase the chance of pregnancy.

Today, that approach has shifted. Most clinics and surrogacy agencies recommend Single Embryo Transfer (SET)—especially when transferring high-quality blastocysts. This reduces the risk of:

• Multiple births (which carry higher medical risks)
• Preterm labor
• Low birth weight

The American Society for Reproductive Medicine (ASRM) also recommends SET for women under 35 using high-quality embryos.

Benefits and Risks of Embryo Transfers

Benefits:

• Allows control over timing and conditions of pregnancy
• Enables use of genetic screening
• Helps couples and individuals with infertility build families

Risks:

• Failure to implant
• Early pregnancy loss
• Risk of multiple pregnancy (if multiple embryos used)
• Emotional and financial stress

Pros and Cons of Fresh Embryo Transfers

• Pros: Fewer steps, no freezing needed; Shorter total IVF timeline
• Cons: Uterine lining may not be optimal; Not suitable if genetic testing is needed; Higher estrogen levels can reduce implantation chances

Pros and Cons of Frozen Embryo Transfers

• Pros: Better synchronization; Allows PGT testing; Uterus recovers from stimulation
• Cons: Slightly longer process; Some embryos don’t survive thawing

For surrogacy arrangements in particular, FET is often the safer and more flexible option.

How To Prepare for Your Embryo Transfer

Preparation depends on whether it's a fresh or frozen cycle. In both cases, it involves:

• Hormonal medications (estrogen and progesterone)
• Uterine lining monitoring via ultrasound
• Blood work to track hormone levels
• Psychological readiness—this is a big step

Surrogates will often start meds weeks before transfer to make sure everything lines up perfectly.

The Embryo Transfer Procedure

The procedure itself is quick—usually 15–30 minutes—and painless.

• A thin catheter is used to insert the embryo through the cervix into the uterus.
• Ultrasound guidance helps place the embryo in the optimal spot.
• No sedation is needed, and light activity is recommended for 24–48 hours.

What To Expect After Your Embryo Transfer

After the transfer, it's all about patience. The embryo may take a few days to implant.

Some women experience:

• Mild cramping
• Spotting
• Mood changes
• Fatigue

These are all normal. The most important thing is to follow the clinic’s instructions and avoid overanalyzing every symptom.

Wait Two Weeks Before Taking Your Post-Transfer Pregnancy Test

The two-week wait is tough—but testing too early can give false results. Blood tests (beta hCG) are the gold standard.

Urine tests may not detect early pregnancy accurately. Your clinic will schedule the test date—trust the process.

Fresh vs. Frozen Embryo Transfer Success Rates

Success rates vary based on age, embryo quality, and medical history. But overall, FETs now outperform fresh transfers in many cases.

According to recent CDC data:

• FETs have similar or higher pregnancy rates compared to fresh
• Lower miscarriage risk
• Better outcomes for babies (higher birth weights, fewer NICU stays)

You can explore data directly through CDC, NICHD, or HHS.

How Much Does an Embryo Transfer Cost?

In the U.S., embryo transfer costs vary based on the clinic and whether it’s part of a larger IVF package.

• Fresh transfer: $10,000–$15,000 (as part of IVF cycle)
• Frozen transfer: $3,000–$6,000 (FET cycle only)
• Additional costs: medications, monitoring, genetic testing, surrogacy agency fees

Some insurance plans may cover part of the process. Check with your provider and explore federal resources.

Embryo Transfers Are Just One Part of Your Family’s Journey

Embryo transfer is not the end—it’s a milestone. Whether you’re a couple navigating infertility or an LGBTQ+ family building through surrogacy, this step is part of something far bigger: your future.

Understanding the ins and outs of embryo transfers helps you make informed choices, work more effectively with your agency or clinic, and stay grounded through every up and down.

And remember: while science plays a key role, heart and hope drive this journey.