There are two different methods of ovulation induction. The first is used for women who are not ovulating spontaneously (irregular or infrequent menstruation). In such cases, the aim is to stimulate the release of one egg a month. This is most easily done by prescribing fertility pills, such as Clomiphene. If this medication is not effective, then injections of a small dose of synthetic follicle stimulating hormones may be necessary.
In the second situation, the woman is ovulating spontaneously but has unexplained infertility or her partner has mild male-factor infertility. In such a case, the aim of ovulation induction is to stimulate the production of 2 to 4 large follicles, so that several eggs will be released. This is most easily achieved by injections of synthetic follicle stimulating hormones. This treatment is combined with intra uterine insemination (IUI) to bring the sperm closer to the egg.
All women using these medications are monitored with vaginal ultrasound scans to observe the response of the follicles in the ovary. Once the leading follicle(s) reaches 18 mm in diameter, the egg is considered mature and ready for ovulation. You may need 2 to 4 scans during one treatment cycle. The different drugs used for ovarian stimulation are:
- Clomiphene Citrate
- synthetic follicle stimulating hormones (FSH and LH)
- Human Chorionic synthetic follicle stimulating hormones (hCG)
You may also want to read:
Ovarian Stimulation Protocols for IVF