The side effects associated with gonadotropin treatment are more common and more serious than those associated with clomiphene, a synthetic drug that is also used to increase gonadotropin production. These side effects include:
- Miscarriage: Up to 35 percent of women who become pregnant following gonadotropin therapy have a miscarriage.
- Ovarian enlargement: This occurs in between 5 and 10 percent of treatment cycles, as multiple follicles make the ovaries larger and tenderer.
- Ovarian hyperstimulation syndrome (OHSS): This potentially life-threatening complication occurs when the drugs stimulate the ovaries too much, though women undergoing fertility treatments who are monitored for side effects have less than a 1 percent risk of developing severe OHSS.
- Breast enlargement in men
- Headache and abdominal pain
Individuals receiving hCG should contact their doctor if they notice any of the following side effects:
- Breast enlargement
- Penis and testicular enlargement
- Development of facial or pubic hair
- A sudden height increase
- Symptoms of an allergic reaction (e.g., hives or skin rash
- Nausea or vomiting
- Passing small amounts of urine
- Stomach or pelvic pain or bloating
- Shortness of breath
- Rapid weight gain
- Symptoms of an allergic reaction (e.g., hives or skin rash)
Common side effects of hCG that do not usually require medical attention include:
- Changes in emotion or mood
- Pain, irritation or inflammation at the injections site