What Are the Functions of Human Chorionic Gonadotropin?

What is Human Chorionic Gonadotropin?

Human chorionic gonadotropin (hCG) is a hormone that an embryo makes right after the mother conceives. The hormone later comes for part of the placenta called the syncytiotrophoblast. It plays an important role in maintaining the pregnancy. It has two sides. One side is identical in substance to three hormones in the adult body, lutenizing hormones, or LH, that stimulate the production of testosterone in men and ovulation in women, FSH hormones that control growth, the onset of puberty, growth and reproduction and TSH, a thyroid-stimulating hormone. The other side is only in hCG and contains encoded amino acids.

Maintaining Pregnancy

The human chorionic gonadotropin plays a role in maintaining the secretion of progesterone, which thickens the walls of the uterus by keeping the corpus leutum from disintegration. The progesterone helps make extra blood vessels and capillaries for the uterus lining so it can support the growth of the fetus.

Protection

The hCG has a high negative charge that protects the growing fetus from rejection attacks by the mother's immune cells during the first trimester. The bad news is that it also may be responsible for morning sickness.

Tests

One way that doctors can tell if a woman is pregnant is by drawing blood or taking a urine sample. It's an early detection hormone test. Doctors test samples for human chorionic gonadotropin. They also check the level for birth defects. If a woman has a growth in her uterus, a test for hCG indicates that it is a molar growth, cancer, an ectopic pregnancy or normal pregnancy. In a man, a high hCG level might mean there's a tumor. These may be very tiny tumors on the testicles detected no other way. Sometimes, the positive test in a man or non-pregnant woman means there's cancer elsewhere, like in the large intestines, liver, lung or pancreas.

Infertility

Often doctors give hCG in conjunction with infertility treatments to help the egg implant and maintain the pregnancy. Since it stimulates the release of the egg, it's one factor responsible for some of the multiple pregnancies.

In Men

In men, human chorionic gonadotropin stimulates the testes. If there's underproduction of testosterone, undescended testes or testicular atrophy, hCG helps. It mimics the lutenizing hormones and sends a message as though it were the hormone to the testes to increase production, which helps with all of the above problems.