HCG or human chorionic gonadotrophin is a hormone that is produced by the cells in the placenta of a pregnant lady. The placenta has several kid of cells and the syncytiotrophoblast cells produce this hormone. Before we discuss the importance of HCG injections, let us talk a little bit about the hormone itself.

HCG has 2 subunits, 1 alpha subunit and 1 beta unit sub unit. The Alpha subunit is almost identical to the Luteinizing hormone and the follicle stimulating hormone (both are hormones secreted by the anterior pituitary gland for regulation of sexual function) while the beta subunit is found only in HCG.

There are four kinds of HCG but the type significant in this context is produced by the syncytiotrophoblast cells of the placenta. Progesterone is a hormone that is essential to maintain the endometrium (the innermost layer of uterus, this is where the embryo implants) for the embryo to implant and grow. The placenta cannot produce enough progesterone to maintain the endometrial layer so it secretes HCG instead. Now this HCG performs an important function and it maintains the corpus luteum in the ovary which secretes progesterone. Corpus luteum is a remnant of the ovarian follicle from which the ovum emerges during ovulation. In the absence of pregnancy it decreases in size and ultimately gets destroyed but HCG maintains it in case of pregnancy. This is needed only in the first trimester because after this the placenta is mature enough to secrete enough progesterone.

The overall function of HCG is to maintain pregnancy which it does by preventing shedding of the built up endometrial layer of Uterus (as is seen in menstruation), promotes blood vessel formation in the uterus, prevents action of the maternal immune system on the placenta or fetus and relaxes any contractions in the myometrial (muscular) layer of the uterus, preventing miscarriage. HCG closely resembles LH which is a hormone in both the sexes that stimulates release of Testosterone in males and ovulation in females.

HCG Injections in case of Infertility

As described earlier, HCG mimics LH. LH peaks in the middle of the menstrual cycle of a reproductively normal lady and leads to ovulation. HCG is administered as injections to cause the follicles in the ovary to mature and get released, leading to ovulation. This is used extensively in case of ladies who are undergoing procedures for assisted reproduction (Such as IVF) as the ovulation can be induced. Ovulation usually takes place after 36-38 hours and this egg can then be harvested for IVF or in case of artificial insemination, the insemination can be planned accordingly to ensure maximal chances of fertilization. However, this cannot be used in the type of infertility in which the ovaries are unable to produce viable ova.

HCG Injections in Males

In males, LH stimulates certain cells called Leydig cells in the testes to produce testosterone. Testosterone is the main male sexual hormone that is responsible for secondary sexual traits, libido, sperm development, etc. In case of deficiency of testosterone or testes that have not descended, HCG may be given as injection to stimulate testosterone production. Testosterone helps in cases of testes that have not descended.

Side Effects

You should always watch out in case any of the following side effects are observed when you are on HCG therapy. In case of women on HCG, the following side effect may be seen:

  1. Breathlessness
  2. Abdominal discomfort or pain
  3. Diarrhea
  4. Swelling in the limbs

For young boys taking HCG injections, one should what our for the following adverse effects:

  1. Signs of early or rapid sexual growth
  2. Pain, secretions or growth of the breasts

In both scenarios, care should be taken to note any signs of allergy to the drug such as itching, difficulty in breathing, hives or dizziness.