In vitro fertilization (IVF) is one treatment option for infertility and increases the chance of pregnancy.
Purpose of In Vitro Fertilization (IVF)
IVF is a procedure where a woman’s eggs (oocytes) are fertilized with sperm outside of the body. Then the embryos are placed back into the uterus in order to achieve pregnancy.
General reasons why we might recommend IVF include:
- Blocked fallopian tubes
- Infrequent or absent ovulation
- Unexplained infertility after other treatments have been unsuccessful
Additionally, if a man has a very low sperm count or other abnormal semen parameters, we may recommend IVF with intracytoplasmic sperm injection (ICSI).
IVF with ICSI can make pregnancy possible when the chance for spontaneous pregnancy is very unlikely.
In Vitro Fertilization (IVF) Procedure
The steps of a typical IVF cycle are as follows:
Step 1: Ovarian Stimulation
- At the beginning of a planned IVF cycle, a woman will generally come in around day three of her menstrual cycle for baseline blood work and an ultrasound.
- Next, injections of follicle stimulating hormone (FSH) are initiated. FSH stimulates the ovaries to produce several mature eggs (oocytes).
- There are many different medication regimens used in IVF cycles. In general, all regimens will include:
- Hormones — such as FSH and, occasionally, luteinizing hormone (LH) — to stimulate the ovaries to produce eggs
- Medications to prevent premature ovulation
- In some situations, you may even begin medications at the end of the cycle prior to the current IVF cycle.
- During ovarian stimulation, we will monitor the progress of developing follicles (fluid-filled cavities that house the oocytes) via ultrasound. And, we'll do blood work to assess egg development.
- Once several mature follicles are present, maturation of the oocytes will be achieved by administering a medication called hcg (human chorionic gonadotropin).
Step 2: Egg (Oocyte) Retrieval
- Approximately 36 hours after you receive hcg to cause maturation of the oocytes, egg retrieval will take place.
- During egg retrieval, you are under conscious (IV) sedation.
- A transvaginal ultrasound with a small needle is passed into the vagina.The needle pierces the wall of the vagina to remove the fluid and the eggs within the follicles in the ovaries.
- Egg retrieval generally takes less than 30 minutes, depending on the number of follicles you have.
Step 3: Fertilization
- An embryologist will examine your collected eggs to assess maturity.
- The mature eggs will be combined with semen obtained from your partner (or a sperm donor) for fertilization. In situations of a very low sperm count or other abnormalities, the ICSI procedure may be performed in order to achieve fertilization.
- Approximately 18 hours later, the oocytes will be examined to see if they have fertilized. Fertilized oocytes are called embryos.
Step 4: Embryo Transfer
- About three days after egg retrieval, you will return to the clinic for an embryo transfer.
- Prior to transferring embryos into the uterus, the embryos are graded to describe their appearance and how many divisions they have undergone. The healthiest-appearing embryos are chosen for transfer.
- Embryo transfer is performed under ultrasound-guidance by placing a small flexible catheter (tube) into the uterus and then injecting the embryos through the catheter. This procedure generally does not require anesthesia or sedation.
- The number of embryos to be transferred will be decided at the time of your consult and this will be determined based on ASRM guidelines.
Often, a couple will have more healthy-appearing embryos than will be transferred in that cycle. In these situations, we offer cryopreservation (freezing) of the embryos.
This allows you to return in the future for a frozen embryo transfer, without having to undergo ovarian stimulation.
Step 5: Progesterone Supplementation
- After the embryo transfer, progesterone supplementation is initiated.
- Progesterone helps maintain early pregnancies and can be administered in a variety of ways. The most common are intramuscular injections and vaginal suppositories.
- Approximately two weeks after embryo transfer, a pregnancy test will be performed. If it is:
- negative, the progesterone supplementation can be stopped
- positive, progesterone supplementation will continue for the first 10-12 weeks of pregnancy
- An ultrasound will also generally be performed within 3 or 4 weeks of an embryo transfer, to assess whether the pregnancy is developing normally.
In Vitro Fertilization (IVF) Success Rates
Success of pregnancy with IVF depends on several factors, including a woman’s age and the reason for infertility.
In general, success rates for women:
- under 35 years old can range from 35 to 50 percent per IVF cycle
- 40 or older are more modest (around 10 percent per IVF cycle)
Risks of In Vitro Fertilization (IVF)
Risks of IVF include:
- Multiple births
- Ovarian hyperstimulation syndrome (OHSS)
- Ectopic pregnancy
Practices to prevent multiple births, namely transferring fewer embryos into the uterus, are generally undertaken.
Multiple births are known to be at higher risk for a variety of pregnancy complications, such as:
- Premature birth
- Growth restriction
- Preeclampsia (hypertension during pregnancy)
Ovarian Hyperstimulation Syndrome (OHSS)
OHSS results from overstimulation of the ovaries and can cause:
- Abdominal distention
- Fluid imbalances
Severe OHSS, requiring hospitalization, occurs approximately 1 percent of the time.
Your physician will discuss all risks with you before performing any procedure.