The most common cause of female infertility is lack of ovulation. Regardless the cause of the lack of ovulation many women respond to one of two common fertility treatments: Clomiphene Citrate (most often given as the medication Clomid) and letrozole (the breast cancer treatment Femara) are both effective fertility treatment due to the stimulation of ovulation.
It is possible to do extensive testing first, tweak dosages, combine with other medications, or these two medicines may be given to women who have menstrual cycles and have not yet conceived, or women who have no menstrual periods, even for those who have PCOS.
Although they work, effectiveness is modest. About 60 to 75% of women who are infertile due to no menstrual periods will ovulate when given these relatively low cost medications. They both work by signaling there is low estrogen and thus more hormones are released to increase the number of eggs ovulated. Clomid is a SERM. Selective Estrogen Receptor Modulators (SERMs) could bind to the estrogen receptor to stimulate estrogen properties or to counter them. For fertility we make use of the fact that Clomid medication binds to the surface of cells the pituitary gland and thus pushes the hormonal factors to produce more growth of the follicle that will eventually produce a fertile egg.
Some side effects from all these medications are possible and it's important to go over those with your gyno.. Because it is however, statistically very safe for both mom and babies, and effective, many physicians will use it very early on for infertility treatment, in the low dosage, for 1-6 cycles. Letrozole is is in the category of medicine called an aromatase inhibitor, essentially blocking the production of estrogen and making estrogen levels transiently very low . It may be better than Clomid based on some recent studies at the University of Nottingham in Derby, England. Dr. Saad Amer who headed these studies also believed there were fewer fetal anomalies with letrozole than with clomifene, however the rates of birth defects were only slightly higher than the rates of birth defects in women who did not use these medications. When women take these medications potential side effects, other than the side effects of the medication administration, include twining, preterm birth, miscarriage, or tubal pregnancy.
Some physicians use very close monitoring of the medications, but others merely recommend timing of sex with ovulation after taking an ovulation medicine. Patients should also discuss with their gyno the fact that Clomid is indicated for infertility treatment, and letrozole for this indication is considered off label.
Most gynos will have you try for pregnancy without medication first, so go in for an appointment to pregnancy plan and decide when it is appropriate to intervene further.