Embryo transfer is the step where an embryo is placed in the uterus through a thin, soft tube called a catheter. It usually takes less than 10 minutes and needs no anaesthetic. It can use a fresh embryo from the same cycle or a frozen one from an earlier cycle.
What embryo transfer is
After eggs are fertilised and embryos have grown in the lab, one embryo is placed in the uterus. This is the final step of IVF or ICSI before the wait for a pregnancy test.
| Feature | Fresh transfer | Frozen transfer |
|---|---|---|
| When | Within about 3 to 7 days of egg collection | In a later cycle, even years later |
| Uterus preparation | Follows the stimulation cycle | Natural cycle with scans, or medicines to prepare the lining |
| Embryo | Not frozen | Thawed first; not all embryos survive thawing |
| Common use | Standard IVF cycles | Spare embryos, or after embryo testing (PGT) |
The embryo is placed in the womb using a thin tube passed through the vagina and cervix. Your doctor chooses which embryo to transfer, and good-quality embryos that are not used may be frozen for future attempts.
Who it is for
- Everyone completing an IVF or ICSI cycle with a suitable embryo
- People using frozen embryos from a previous cycle
- People whose embryos were tested with PGT
ASRM guidance, based on good evidence, recommends abdominal ultrasound guidance and a soft catheter during transfer, and does not recommend bed rest afterwards.
Best practice for most people is elective single embryo transfer (eSET). It reduces the serious health risks of twins without lowering success for most patients.
Step by step
- Preparing the liningFor frozen transfer, scans check the lining in a natural cycle, or medicines prepare it if periods are irregular.
- Choosing the embryoThe embryologist selects the embryo based on its development. Frozen embryos are thawed on the day.
- SpeculumYou lie on a couch and a speculum is placed in the vagina, as in a smear test.
- Catheter placementA thin, soft catheter carrying the embryo is passed through the cervix into the uterus, guided by ultrasound on the abdomen.
- Releasing the embryoThe embryo is gently released into the uterine cavity and the catheter is withdrawn.
- AfterwardsYou continue progesterone as advised and take a pregnancy test around 9 to 16 days later.
| At a glance | What sources describe |
|---|---|
| Anaesthesia | Not required |
| Length | Typically under 10 minutes |
| Feels like | Similar to a pelvic exam or Pap smear |
| Afterwards | Normal activities can usually resume straight away |
| Pregnancy test | Blood test about 9 to 14 days later (Cleveland Clinic); NHS clinics give a home test for about 16 days later |
What it feels like
- No anaesthetic is usually needed, unless a condition makes it uncomfortable.
- Most people feel mild pressure, similar to a pelvic exam or smear test.
- The procedure usually takes less than 10 minutes.
- Mild bloating, cramping or spotting afterwards are common; you can usually resume normal activities.
The two-week wait can feel long. Avoid testing too early at home, as results may be confusing; use the test date your clinic gives.
- Bloating and constipation.
- Mild cramping and light spotting.
- Breast tenderness, linked to high oestrogen levels.
Take your pregnancy test on the date your clinic gives you. Testing too early can give a misleading result.
How to prepare
- Take progesterone and other medicines exactly as prescribed
- Return to normal activities after the transfer; guidelines advise against bed rest
- Decide with your doctor how many embryos to transfer before the day
- Do not stop progesterone without your doctor's advice
- Do not ask for extra embryos to be transferred to raise the odds without discussing the risks
Risks and side effects
| Risk | What sources say |
|---|---|
| Multiple pregnancy | In the US, about 30% of IVF pregnancies are twins when more embryos are transferred; twins carry higher risks of preterm birth and complications. |
| Ectopic pregnancy | IVF carries a small risk of ectopic pregnancy, so early scans check where the pregnancy is. |
| Thawing loss | Not all frozen embryos survive thawing; very occasionally none survive. |
| No pregnancy | No method can reliably predict which embryo will implant. |
Contact your clinic urgently for heavy bleeding, severe one-sided pain, fever or feeling faint after transfer.
If more than one embryo is available, your doctor should discuss the risks and benefits of transferring more than one. Multiple pregnancy carries higher risks for both mother and babies. Ectopic pregnancy, where an embryo implants outside the womb, is another recognised risk.
If the test is negative, give yourself time to recover and lean on support. Remaining good-quality embryos may be frozen for future attempts, with storage costs.
How DBN does it
- DBN transfers one embryo at a time (single embryo transfer) to reduce twin risk.
- Embryos are cultured to day 5 (blastocyst); others can be vitrified and stored at −196 °C for later frozen transfer.
- IVF & ICSI is about 450,000 THB per cycle including blastocyst culture, over 4–6 weeks. First consultation is free; prices are confirmed at consultation.
When to see a doctor
- Heavy bleeding or severe pain after transfer
- Fever or unusual discharge
- A positive test, to arrange your early pregnancy scan
- A negative test, to plan next steps with your doctor
Questions & answers
Is frozen transfer less safe than fresh?
The UK regulator says using frozen embryos is just as safe as using fresh ones.
Will transferring two embryos double my chances?
No. For most people, single embryo transfer does not lower success, while two embryos raise the risk of twins.
Does transfer need anaesthetic?
Usually not. It feels similar to a smear test and is over in minutes.
Should I rest in bed after transfer?
No. Studies found no benefit from bed rest, and ASRM guidance advises against it.
Related DBN services
Related articles
Sources
- IVF (In Vitro Fertilization): Procedure & How It Works — Cleveland Clinic
- IVF — NHS
- Decisions to make about your embryos — HFEA
- Embryo freezing — HFEA
- Elective single-embryo transfer (eSET) patient education fact sheet — ASRM / ReproductiveFacts.org
- Performing the embryo transfer: a guideline (Fertility and Sterility, 2017) — ASRM Practice Committee