Fresh embryo transfer: the timeline from retrieval to transfer

Expect the days after your egg retrieval to move quickly. The lab checks for fertilization the next day, and updates can keep coming until your clinic confirms the transfer day. A fresh transfer also depends on how you are recovering, your hormone results and your risk of OHSS, so the plan can still change to freezing embryos. The warning signs are near the end of this page.

Your clinic's plan always comes first.

What is a fresh embryo transfer?

In a fresh embryo transfer, your embryo is placed in your uterus in the same cycle as your egg retrieval, and it is never frozen. After retrieval, the lab joins your eggs with sperm, and the eggs that fertilize become embryos. A few days later, an embryo suitable for transfer is placed in your uterus.

This usually happens 3 or 5 days after the retrieval. Your clinic will choose the day.

If other embryos suitable for freezing develop, they can be frozen. You could use them in a later frozen embryo transfer.

How your clinic decides on a fresh transfer

Your team keeps checking these things until transfer day:

• How your embryos develop. The lab watches whether embryos keep growing, and which one is suitable for transfer.
• How you recover after retrieval. Signs of OHSS, when the ovaries overreact to the fertility medicines, can lead your clinic to freeze embryos instead.
• Your hormone results. A rise in progesterone near the end of stimulation may lower the chance of pregnancy from a fresh transfer. Your clinic may freeze embryos when this happens and transfer in a later cycle.
• Your uterus. A finding such as a polyp, a small growth in the lining, can affect whether an embryo can implant.
• Genetic testing plans. If embryos are tested with PGT-A, freezing them gives time for results to come back.

The fresh transfer timeline

Your clinic may count days differently.

Day	What happens	What you might hear
Retrieval day (day 0)	Eggs are collected and joined with sperm	How many eggs were collected
Day 1	The lab checks for signs of fertilization	How many eggs fertilized
Day 3	Embryos have about 6 to 10 cells	Whether transfer is on day 3 or day 5
Day 5	Embryos that keep growing form a fluid space inside	How many reached the blastocyst stage
Transfer day	One embryo (sometimes more) is placed in your uterus	What happens to the other embryos
Days after transfer	A pregnancy test	Your test date

A blastocyst is an embryo at about day 5. It has a small space filled with fluid inside it. Embryo for embryo, blastocysts implant more often than day 3 embryos.

That does not make day 5 best for everyone. ASRM says the evidence supports blastocyst transfer for people with a good outlook. Some embryos that look fine on day 2 or 3 stop growing before day 5, so waiting can raise the chance of having no embryo to transfer. Your clinic weighs this when it picks day 3 or day 5.

For more on how embryos grow each day, see embryo development.

Embryo updates: what the calls are about

Your clinic may call with updates in the days after retrieval.

The numbers can get smaller from one call to the next. Some eggs will not fertilize or grow normally, which is why IVF aims for more than one egg. Falling numbers come from how eggs and embryos develop in the lab. They are not a sign that you did something wrong.

Your medicines between retrieval and transfer

The stimulation medicines and the retrieval can lower how much progesterone your ovaries make. Progesterone is a hormone that helps your uterine lining get ready for an embryo, so your doctor may prescribe it to make up the difference.

Progesterone is usually started on the day of retrieval or the day after. It can be a shot into a muscle, or a gel, insert or tablet placed in the vagina. Your clinic chooses the form and tells you exactly how to take it. If a dose is late or missed, call your clinic for instructions rather than guessing how to make it up.

When a fresh transfer turns into a freeze

Sometimes a clinic stops a fresh transfer and plans to freeze embryos instead, for any of the reasons above. With OHSS (ovarian hyperstimulation syndrome), fluid leaks into the belly, and a pregnancy can make it worse or make it last longer. Freezing the embryos and waiting can help OHSS settle faster.

A change of plan does not mean you will have embryos to freeze, because the lab is still watching how they grow. Learn more on the freeze-all cycle page.

Ask your team why the plan changed, what needs to happen before a frozen transfer, and who will contact you about the next step.

What if there is no embryo to transfer?

Sometimes no eggs fertilize at all, even with ICSI. ICSI is when the lab places one sperm straight into each egg. In other cycles, eggs fertilize but the embryos stop growing later, before any reaches a stage suitable for transfer.

Ask for a visit to talk about what the lab saw, why it may have happened and what could change next time, and bring someone with you if you can.

Why some people choose a fresh transfer

A fresh transfer can lead to a pregnancy sooner, because freezing delays the transfer. A large Cochrane review found probably little or no difference in the overall chance of a baby between a fresh-first plan and freezing all embryos. In a 2025 trial in China of 838 women with a low chance of IVF success, more had a baby after the first transfer with a fresh transfer (40%) than with freeze-all (32%). See fresh vs frozen transfer for what these studies did and did not measure.

How many embryos are transferred?

The goal of treatment is one healthy baby at a time, because twins or more carry more risk. U.S. guidance from ASRM sets limits by age, outlook and embryo stage, and it leaves room for each person's situation:

• Under 35 with a favorable outlook: one embryo is strongly encouraged, whatever its stage.
• 35 to 37 with a favorable outlook: one embryo should be strongly considered.
• An embryo with a confirmed normal genetic test result: one embryo, at any age.
• At older ages, or with a less favorable outlook, more than one may be an option.

Fresh transfer checklist

Use this list in the days after your retrieval:

• Write down your retrieval day and count forward to day 3 and day 5.
• Start progesterone exactly when your clinic says.
• Set reminders for every dose.
• Keep your transfer day open until the clinic confirms it.
• Read the transfer day guide a day or two ahead.
• Save your clinic's after-hours number in your phone.

Timing questions to ask your clinic

• Will my transfer be on day 3 or day 5, and when will I know?
• What findings would make you recommend delaying my transfer, and when will that decision be made?
• When do I start progesterone, and in what form?
• How many embryos do you suggest I transfer, and why?
• What happens to embryos that are not transferred?
• When is my pregnancy test?

When to get help

Call your clinic right away, day or night, if you have:

• A fever of 100.4°F (38°C) or higher.
• Heavy bleeding: soaking a full-size pad with bright red blood in less than an hour, or bleeding heavier than a period. Before a transfer, call for bleeding your clinic did not tell you to expect or a brown, watery discharge. After one, call for any bleeding.
• Belly or pelvic pain that is severe, gets worse, or isn't eased by the pain relief your clinic recommended.
• Pain and bloating in your belly, or bloating that is getting worse.
• Nausea and vomiting, nausea that won't go away, or you can't keep fluids down.
• Peeing less than usual, even if you are not thirsty.
• Fast weight gain. Your clinic will tell you its number, but do not wait to reach a weight threshold if you feel unwell.
• Before a transfer: sudden belly pain, dizziness, lightheadedness, or feeling faint.
• Pain, redness or warmth in an arm or leg.
• Blood in your urine, or pain when you pee or poop.
• Discharge from your vagina that smells bad, after a retrieval.

Tell your clinic at your next contact about other milder symptoms that are new, don't go away or slowly get worse.

What comes next

After the transfer, the next step is the wait for your test. Read what to expect after embryo transfer.