Gonadotropins

Gonadotropins are protein hormones that control the ovaries and testes. In fertility care, the term usually means drugs given by injection. These drugs trigger the release of an egg (ovulation induction) or make the ovaries grow more follicles (ovarian stimulation). One type is recombinant FSH (follitropin alfa/beta). Another is human menopausal gonadotropin (hMG), which has both FSH and LH activity.

These drugs make follicles grow directly. They bypass the hypothalamic-pituitary axis, the brain's control of the ovaries, entirely.

In NaProTechnology practice, clinicians generally weigh oral drugs to trigger ovulation before these injections. The oral drugs are letrozole or clomiphene. The injections may also suit certain cases. One is hypogonadotropic anovulation, in which the brain's drive to ovulate is missing.

When clinicians use them, they watch each cycle closely with a series of transvaginal ultrasounds. This monitoring spots many follicles growing at once. It also lowers the risk of ovarian hyperstimulation syndrome (OHSS).

The guiding idea is mild stimulation. Doses stay as low as will work. In Restorative Reproductive Medicine, these drugs are a targeted step aimed at a diagnosed cause. They are not a default next step.