How Does IVF Work
In vitro fertilization is a type of assisted reproductive technology that is done when a couple is having difficulty conceiving a child. It is also referred to as IVF and involves putting the egg and sperm together outside of the woman’s body, allowing the fertilized egg to become a several cell embryo and then transferring the embryo into the uterus.
Common reasons why IVF is used include the following:
- Couples who have a genetic disorder (only healthy embryos are allowed to transfer into the uterus)
- Women who have had a tubal ligation but now want to become pregnant
- Women with problems ovulating or who have premature ovarian failure
- Women with fibroids on their uterus
- Male infertility with a decrease in sperm count or sperm motility
- Fallopian tube blockage (from infections possibly)
- Couples with unexplained fertility
Steps in In Vitro Fertilization
There are five basic steps to in vitro fertilization:
- Giving Fertility Medications. The woman is given medications that maximally stimulate the ovaries so that the ovaries will yield many fertilizable eggs.
- Collect the eggs. This involves putting a catheter into the pelvic space and “sucking out” all of the ripe eggs at the time of ovulation.
- Getting the sperm. The man must give a semen sample to mix with the eggs that have been harvested.
- Mix the sperm and egg together. This is done in an appropriate cellular environment and is when the sperm and egg can come together in fertilization outside of the body.
- Wait until the fertilized eggs have divided. The egg is allowed to divide a few times so that about 8-celled embryos are transferred into the uterus.
- Usually 1-3 eggs are transferred into a uterus that has been prepared and is ready to implant the embryo(s).
Side Effects
Most of the time, there are no side effects and you can go back to your normal activities of daily living after the embryos have been transferred into the uterus. Some possible side effects include the following:
- Cramping after transferring the ovaries
- Passing a small amount of liquid from the vagina after transfer of the embryos
- Constipation
- Breast tenderness
- Bloating
You should see the fertility specialist if you have any of these symptoms after in vitro fertilization:
- Fever of greater than 100.5 degrees Fahrenheit
- Bloody urine, which may mean you have a bladder infection
- Pain in the pelvic region
- Heavy bleeding from the vagina
Risks of In Vitro Fertilization
There are some risks of in vitro fertilization. You can have side effects from the hormones needed to stimulate the ovaries or to maintain the uterus after transfer of the embryos. These include hot flashes, bloating, mood swings, headaches, and abdominal pain. You can overstimulate the ovaries, resulting in ovarian hyper-stimulation syndrome or OHSS.
In OHSS, you might develop the following:
- Abdominal pain and bloating
- Feeling faint
- Being short of breath
- Having decreased urination
- Having nausea or vomiting
- Sudden weight gains over a few days
Other risks of IVF include the following:
- Bleeding, bowel damage, or infection after egg retrieval
- Increased chance of multiple fetuses (this is less likely of only 1-2 embryos are transferred on any given cycle
- Increased risk of preterm birth or low weight for gestational age infant
- Increase in cost. The IVF procedure is expensive, costing at least $12,000 or more per cycle you undergo.
Success rate of In Vitro Fertilization
There are a number of factors that play into your success or failure at obtaining a child through IVF, including the age of the mother, the mother’s reproductive history, lifestyle factors, and the cause of infertility.
In the US, there is a 41-43 percent chance of having a live birth per IVF cycle if the woman is under the age of 35. This decreases to 33-36 percent in women between 35 and 37 years of age. The live birth rate is 23-27 percent in women between 38 and 40 years of age, and only 13-18 percent women who are over the age of 40 years.
If either the female egg or the male sperm is faulty, you always have the option of using donor eggs, donor sperm, or donor embryos. You may wish to seek mental health treatment to deal with the issues around having a donor provide you with a child rather than your own genetic child.
How many embryos to transfer?
When IVF was new, it was not unexpected to put up to 8 eggs per cycle in the woman, hoping that at least one would take and create a live birth. Now that IVF is much more successful and the risk of a high multiple pregnancy exists, many doctors are collecting multiple eggs, fertilizing them, and transferring only 1-3 eggs at a time, freezing the rest of the embryos should they be needed in the future. This means you’ll have only a chance of triplets at the most.
References:
- http://americanpregnancy.org/infertility/in-vitro-fertilization/. Accessed 4/27/16.