The side effects of human chorionic gonadotropin (HCG), a sex hormone responsible for pregnancy, include blood clots, birth defects, and an increased risk of cancer, particularly if too much of the hormone is administered through medical supplementation. A pregnant woman’s body naturally produces HCG shortly after a fertilized egg leaves the fallopian tube and attaches to the uterus. Within five to 10 days after conception, the pregnant woman’s body produces increased levels HCG to ensure the baby develops properly. HCG side effects from natural production are possible; the bigger risk, however, is for people who seek artificial sources of HCG through doctor-administered injections or pills.
A woman who is in menopause or otherwise unable to conceive might use HCG to increase fertility and stimulate ovulation. HCG side effects in this situation would include the risk of multiple fertilization and multiple births. Quadruplets, triplets, and twins are highly possible for women using HCG as a fertility treatment.
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Doctors are typically reluctant to use HCG on women with a history of cysts or cancers, because the sex hormone can be a cancer trigger that encourages tumor growth in the breasts or ovaries. Women with uterine problems are also not considered good candidates for HCG treatments, because the uterus can be overstimulated, leading to a bleeding, thicker lining, and other uterine abnormalities. Sufferers of epilepsy and other brain disorders are often discouraged from taking HCG, because side effects include mental confusion and nervousness. Women who’ve used HCG to get pregnant are at risk of giving birth to babies with Down syndrome and other chromosomal disorders.
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Pregnant women are not the only users of HCG. Men also produce this hormone, but in very small quantities. HCG in men helps with development of sperm and testicles. For this reason, it has become popular for athletes and weightlifters to pair HCG supplements with steroids in hopes of combating the negative effects of the latter, which can include shrunken testicles and reduced sperm count.
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Athletes who use HCG in this way also risk the HCG side effects of cancer and blood clotting. Many countries ban HCG in sports training and major competitions, because many governments consider it an illegal enhancement. Male users of HCG supplementation risk inhibiting natural testosterone production through the pituitary gland. Among the positive HCG side effects is weight loss for both genders. It is possible for both men and women to receive prescriptions for natural or synthetic HCG to administer up to three times a week at home.