The Process Of In Vitro Fertilization (IVF) For Pregnancy
In vitro fertilization (IVF) is used to treat fertility problems and is the most effective type of assisted reproductive technology. IVF involves combining a man’s sperm and a woman’s egg in a laboratory dish, in order to promote fertilization. The resulting embryo is then transferred to a woman's uterus to implant and develop naturally. This procedure may be performed utilizing your own eggs, your partner’s sperm, donor eggs, donor sperm, or a gestational carrier (a woman who will then carry the pregnancy to term). Usually, two to four embryos are placed in a woman’s uterus at once, which may result in multiple pregnancies. The success rate of IVF depends on a myriad of factors including mother’s age, lifestyle factors, and cause of infertility.
Why IVF Is Performed?
IVF is utilized to treat infertility. Infertility is defined as the inability to become pregnant after one year of unprotected intercourse. Approximately 10 percent of men and women of reproductive age are affected by infertility. Common causes of female infertility includes:
- Advanced age
- Blocked or damaged fallopian tubes
Common causes of male infertility include:
- Decreased sperm count
- Immobile Sperm
- Blockages that prevent sperm delivery
What Can You Expect From The Process of IVF?
There are five basic steps to IVF:
- Step 1 – Stimulation or super ovulation: Fertility drugs are provided to stimulate the ovaries to produce multiple eggs, instead of a single egg that normally develops each month. Multiple eggs are needed as some eggs will not fertilize or develop normally after fertilization. During treatment, a doctor will use vaginal ultrasounds to monitor the development of fluid-filled ovarian cysts where eggs mature. Blood tests also will be used to measure your response to ovarian stimulation medications. Estrogen levels typically increase as follicles develop and progesterone levels remain low until after ovulation. When the follicles are ready for egg retrieval (typically after eight to 14 days) given human chorionic gonadotropin (HCG) or other medications will be given to help the eggs mature.
- Step 2 – Egg Retrieval: Egg retrieval is performed as an outpatient procedure, although the patient may be sedated during this process. Eggs are typically retrieved approximately thirty-six hours after the HCG injection and before ovulation. A clinician will use an ultrasound probe to identify the follicles, which house the eggs. Once the follicles are identified, a thin needle is inserted through the vagina and into the ovary and follicles. The needle is attached to a suction device, which draws the eggs and fluid out of each follicle, one at a time. The procedure is repeated for the other ovary. Some women may experience cramping up to a day after the procedure.
- Steps 3 and 4 – Insemination and Fertilization: Healthy sperm that is obtained from a donor or a partner is placed with mature eggs, and incubated overnight. The sperm will typically fertilize the egg a few hours after incubation. In some cases, a clinician may inject the sperm directly into the egg in order to enhance the chances of fertilization.
- Step 5 – Embryo Transfer: Embryos are placed into the woman’s womb three to five days after egg retrieval and fertilization. A clinician will insert a thin tube containing the embryos into the woman’s vagina and up into the womb. If an embryo implants and grows then a pregnancy will ensue. More than one embryo may be placed into the womb at the same time, which can lead to multiple births.
Risk factors associated with IVF include:
- Ovarian hyperstimulation syndrome. Use of injectable fertility drugs, such as human chorionic gonadotropin (HCG) can cause ovarian hyperstimulation syndrome, in which your ovaries become swollen and painful. Signs and symptoms include mild abdominal pain, bloating, nausea, vomiting and diarrhea and typically last a week. If you become pregnant, however, your symptoms might last several weeks.
- Complications associated with egg retrieval. These include reactions to anesthesia, bleeding, infection, and damage to structures surrounding the ovaries, including the bowel and bladder.
- Premature delivery and low birth weight. Research suggests that use of in vitro fertilization slightly increases the risk that a baby will be born early or with a low birth weight.
- Multiple pregnancies. In vitro fertilization increases the risk of multiple pregnancies if more than one embryo is implanted in your uterus. Multiple pregnancies carry a higher risk of early labor and low birth weight than do single pregnancies.
- Emotional and Financial Stress. Use of in vitro fertilization can be financially, physically and emotionally exhausting
In the United States, the live birth rate for each IVF cycle started is approximately:
- 30 to 35 percent for women under age 35
- 25 percent for women ages 35 to 37
- 15 to 20 percent for women ages 38 to 40
- 6 to 10 percent for women ages over 40