FSH injections are given below the skin to directly stimulate follicle growth in the ovaries. FSH, which stands for follicle-stimulating hormone, is released by the pituitary gland. In women, it stimulates the production of eggs and the hormone estradiol during the first half of the menstrual period, before ovulation. FSH injections are typically used as a fertility aid for women having difficulty conceiving, although they can be given to men as well to stimulate sperm production.
Conception only occurs when certain conditions are met within the woman’s body. One of these conditions requires the ovaries to release an egg for fertilization. While all women are born with a set number of eggs, typically only one egg reaches maturation during each cycle. The follicles surrounding the egg enable this maturation, and FSH, as the name implies, stimulates those follicles.
When the hormone levels are too low, a physician may prescribe a course of FSH injections. The hormone is typically combined with another important reproductive hormone, the luteinizing hormone (LH). In women, LH helps increase the amount of estrogen in the follicle cells and stimulates ovulation.
Prior to recommending FSH injections, a fertility specialst orders a test to determine the hormone’s level in the body. This is performed through a blood draw, and is usually done as part of an overall fertility workup. Both excessively high and low levels can interfere with fertility, but FSH injections are only given when the body isn’t producing enough of the hormone. Low levels of FSH and LH indicate secondary ovarian failure, which may be caused by a hypothalamic or pituitary problem. The FSH test can also be used to help diagnose other medical conditions, such as early or late puberty in both boys and girls.
FSH injections used to increase the chances of conception are given once daily over a period of eight to 10 days. It is a subcutaneous injection, meaning the fluid is injected right beneath the skin rather than into a muscle. Transvaginal ultrasounds and blood tests are performed on four to five mornings during the treatment cycle. Intrauterine insemination is typically recommended to increase the odds of conceiving, and couples are advised to avoid sexual intercourse for 36 hours prior to the procedure.
Side effects of FSH injections for women include irritation at the injection site, bloating and pelvic discomfort. In rare cases, women may experience nausea and vomiting, indigestion, shortness of breath and rapid weight gain. When used in men, side effects may include dizziness, fainting, headache, loss of appetite, shortness of breath, and irregular heart rate.
In addition to possible side effects, FSH injections carry a few risks that women should be made aware of prior to the treatment cycle. The highest risk is multiple pregnancies, with a 25 percent risk for twins, less than five percent for triplets, and less than one percent for multiples of more than triplets. Additional risks include enlarged ovaries, blood clots, and twisted ovaries.
The success rate of the injections depends on numerous factors, including the woman’s age and general state of health, and the timing of intercourse or insemination. Average success rates range from 10-20 percent per cycle. Each cycle can cost up to several thousand dollars including office fees. Some insurance plans cover infertility treatments and may offset the fees, while others exclude such treatments from their policy, leaving the patient to carry the entire financial burden.