During in vitro fertilization (IVF), eggs and sperm are brought together in a lab to allow the sperm to fertilize an egg. With IVF, you can use any combination of your own eggs and sperm and donor eggs and sperm.
After IVF, one or more fertilized eggs are placed in the uterus.
- Ovarian stimulation and egg retrieval.
To prepare for a procedure using your own eggs, you will likely need hormone treatment to control ovulation and make your ovaries grow multiple eggs at once. This is often done with shots of gonadotropin-releasing hormone analogue (GnRH agonist or GnRH antagonist) and gonadatropins (such as follicle-stimulating hormone (FSH)). You will get these hormone shots every day for about 1 to 2 weeks.
Your doctor will check your blood estrogen levels and will use ultrasound to see how your follicles are developing. Your dose may change based on test results. And you are monitored frequently with transvaginal ultrasound and blood tests. If follicles fully develop, you are given a human chorionic gonadotropin (hCG) injection to stimulate the eggs to mature. The mature eggs are collected 34 to 36 hours later. This is done with needle aspiration guided by ultrasound. Most people have pain medicine and sedation for this procedure.
- Sperm collection.
Sperm are collected by means of masturbation or by taking sperm from a testicle through a small incision. This procedure is done when a blockage prevents sperm from being ejaculated or when there is a problem with sperm development. Sperm may have been collected and frozen at an earlier time. In that case, the sperm are thawed on the day the eggs are collected.
- Fertilization and embryo transfer.
The eggs and sperm are placed in a dish. They are incubated with careful temperature, atmospheric, and infection control for 48 to 120 hours. About 2 to 5 days after fertilization, the best fertilized eggs are selected. One to four are placed in the uterus. This is done with a thin flexible tube (catheter) that is inserted through the cervix. The other eggs may be frozen (cryopreserved) for future attempts.
- Pregnancy and birth.
Any embryos that implant in the uterus may then result in pregnancy and birth of one or more infants.
What To Expect
Overall, in vitro fertilization (IVF)-related injections, monitoring, and procedures can be emotionally and physically demanding. Superovulation with hormones requires regular blood tests, daily injections, frequent monitoring by your doctor, and harvesting of eggs.
These procedures are done on an outpatient basis. They require only a short recovery time. You may be advised to avoid strenuous activities for the rest of the day or to be on bed rest for a few days. This depends on your condition and what your doctor recommends.
Why It Is Done
IVF may be a treatment choice if you have:
- Missing or blocked fallopian tubes.
- Severe endometriosis.
- A partner with low sperm counts.
- Infertility that can't be explained and has lasted a long time.
- A low number of eggs.
- Irregular menstrual periods or problems with releasing an egg (ovulation).
Other reasons you may choose IVF include:
- You had surgery to reverse a tubal ligation ("having your tubes tied"), and it didn't work.
- You had artificial or intrauterine insemination, and it didn't work.
- You want to test for inherited disorders before embryos are transferred.
- You plan to use donor eggs or donor sperm.
- You plan to have someone else (a surrogate) carry the baby.
How Well It Works
While many people have babies after in vitro fertilization (IVF), success depends on many different things. Almost all assisted reproductive technology (ART) procedures are done using IVF.
Birth rates resulting from a single cycle of IVF using a woman's own eggs are about 30% to 40% for women age 34 and younger, then rates decrease steadily after age 35.footnote 1 The aging of the egg supply has a powerful effect on the chances that an assisted reproductive technology (ART) procedure will result in pregnancy and a healthy baby.
- Cause of infertility.
Infertility can be caused by problems with the reproductive system. Some of these causes can include problems with the fallopian tubes, with ovulation, or with the sperm.
- Pregnancy history.
A woman who has already had a live birth is more likely to have a successful ART procedure than a woman who hasn't given birth before. This "previous birth advantage" gradually narrows as women age from their early 30s to their 40s.
- Own eggs versus donor eggs.
Birth rates are affected by whether ART procedures use a woman's own eggs or donor eggs. Many women over age 40 choose to use donor eggs, which greatly improves their chances of giving birth to healthy babies. For each cycle of in vitro fertilization:footnote 1
- Using her own eggs, a woman's chances of having a live birth decline from around 35% in her late 20s, to around 20% at about age 38, and to 4% by about age 43.
- Live birth rates are about the same among younger and older women using donor eggs. Women in their late 20s through mid-40s average about a 55% birth rate using fresh (not frozen) embryos.
- Frozen embryos versus fresh embryos.
Donor-frozen IVF embryos from a previous IVF cycle that are thawed and transferred to the uterus are less likely to result in a live birth than are donor-fresh (newly fertilized) IVF embryos. But frozen embryos are less expensive and less invasive for a woman, because superovulation and egg retrieval aren't needed.
In vitro fertilization (IVF) increases the risks of ovarian hyperstimulation syndrome and multiple pregnancy.
- Superovulation with hormone treatment can cause severe ovarian hyperstimulation syndrome. Your doctor can reduce this risk by closely monitoring your ovaries and hormone levels during treatment.
- The risk of a multiple pregnancy is directly related to the number of embryos transferred to the uterus. Multiple pregnancies are high-risk for both the mother and the fetuses.
There may be a higher risk of birth defects for babies conceived by certain assisted reproductive techniques, such as IVF. Talk with your doctor about these possible risks.
Embryo transfer success versus the risk of multiple pregnancy
For a woman over age 35 to have the best chance of conceiving with her own eggs and carrying a healthy pregnancy, she may choose to have more embryos transferred than a younger woman would. But this increases her risk of multiple pregnancy.
Because of the risks to the babies of multiple pregnancy, experts recommend limiting the number of embryos transferred. Your doctor will recommend a certain number of embryos to be transferred based on your age and specific situation.
Women over 40 have a high rate of embryo loss when using their own eggs. Instead, older women can choose to use more viable donor eggs. If you're using donor eggs, the number of embryos you receive will be based on the age of your donor.
Current as of: August 2, 2022
Author: Healthwise Staff
Medical Review:Kathleen Romito MD - Family Medicine & Adam Husney MD - Family Medicine & Femi Olatunbosun MB, FRCSC - Obstetrics and Gynecology