Injectable medications are used for IVF or IUI cycles. One of the main processes in an IVF or IUI treatment cycle is the controlled stimulation of the ovaries, to produce eggs. The medications used in ovulation induction are called gonadotropins. Brand names include Follistim, Gonal-F, Menopur, Bravelle, and Repronex. Gonadotropins are primarily used to treat two types of women: 1) those who do not ovulate, ovulate irregularly, or have failed to conceive using Clomiphene citrate (Clomid) and 2) women who ovulate on their own, but may need help in producing multiple eggs, and whose bodies would benefit from the enhanced hormonal environment.
How Do They Work?
Gonadotropins are natural hormones that trigger the ovaries to make eggs. They are generally safe to use, but do require experience and careful monitoring.
In a natural menstrual cycle without any medications, a woman produces one or two follicles, which are fluid filled sacs that contain an egg. The growth of the eggs and their release from the follicles are influenced by the secretion of two hormones from the pituitary gland: Follicle Stimulating Hormone (FSH); and Luteinizing Hormone (LH), both known as gonadotropins.
When a woman becomes menopausal, her pituitary gland secretes large amounts of these hormones in an attempt to stimulate the ovaries, which no longer function. Gonadotropins (other than Follistim and Gonal F) are manufactured by extracting FSH and LH from the urine of post-menopausal women. Menopur contains both FSH and LH, while Bravelle contains only FSH.
For a woman going through infertility treatments, these extracts must be injected and cannot be taken orally, because they would be digested by the stomach.
Recently, gonadotropins (Gonal-F, Follistim) have been manufactured in the laboratory using recombinant technology, which allows a pure form of FSH to be produced. This is not a human tissue or urinary by-product, it is a recombinant FSH. Since it is more pure, it may be self-injected, using a small needle just under the skin.