HOW DOES IT HELP IN FERTILITY TREATMENT?
In early pregnancy, upto 12 weeks, pregnancy is not so stable unlike the latter half. Progesterone from the corpus luteum will be maintaining the pregnancy in the early stages and this responsibility gets shifted to placenta in the later part of the first trimester. By 12 weeks, placenta completely takes over. HCG secreted by the placenta does this job.
Also during the early stages of pregnancy, when the woman has bleeding, HCG injection is given to have a stable placental support, so that pregnancy continues uneventfully without further episodes of bleeding. HCG works because of its similarity in structure to LH, an injection of HCG, thus it works when there is a mature egg follicle in the ovary by causing the egg to mature and be released.
There are various methods of how it can be used, it can be used alone or in an ovulation induction cycle as with intrauterine insemination or during in vitro fertilization.
The procedure is as follows -
HCG medication is taken once there is a mature egg follicle in the ovary. The specific time or the period to take this medicine would be specified by the doctor. If not taken on time, this needs to be reported to the doctor, in case any adjustments need to be made to avoid complications. If one has intercourse or intrauterine insemination, ovulation will occur approximately 36 hours later, so the day of the injection and two days following it are the critical days. In case of having an egg retrieval as in an IVF cycle, it will occur close to that 36-hour mark so as to optimize the maturation but avoid ovulation.
But normally in infertility treatment, the first line of drug is not the HCG injection. Progesterone, micronized or non micronized, by different routes, is the preferred choice.
Natural micronized progesterone, that too by vaginal route is the first line of drug to maintain the ongoing gestation.
One needs to be well aware of the fact that HCG is the hormone detected in urine pregnancy tests, taking HCG medication might result in it persisting in a female body(and urine) for upto a time period of 2 weeks thus if one takes pregnancy test during that time frame, it will be positive but that will be because of the medication. One has to wait upto 2 weeks after the administration to ensure that the positive pregnancy test is due to actual pregnancy (error free result) and not due to the HCG medication.
Thus HCG injections help in conceiving and increases the chances of multiple pregnancies that mean triplets, twins, etc, when administered as subcutaneous or intramuscular injection.