Fertility Medications: Progesterone
Do patients really need progesterone with ovulation augmentation?
The luteal phase of the menstrual cycle is the two week period following ovulation. When couples use injectable gonadotropins (Follistim, Gonal-F, or Menopur) to undergo superovulation, Carolina Conceptions recommends that women use vaginal progesterone supplementation for luteal phase support. Progesterone supplementation should begin four days after Ovidrel, that is, two days after timed intercourse or intrauterine insemination. The progesterone can be administered in multiple forms, which includes 50 mg vaginal suppositories, Crinone vaginal gel, or Endometrin vaginal inserts. All vaginal routes of progesterone are absorbed through the vagina and act directly on the uterus, with no significant effects on circulating blood levels. The progesterone acts directly on the target, which is the inner lining of the womb, or the endometrium. Unfortunately oral progesterone is not effective for this purpose. Often the progesterone is continued for 8 to 10 weeks of gestation. After this time the placenta makes sufficient amounts of progesterone to sustain the pregnancy.
Why is progesterone prescribed?
The injectable gonadotropins cause the ovaries to produce multiple follicles which elevate estrogen levels. The high estrogen levels can cause the pituitary to significantly reduce the release of LH, which is what in turn is supposed to cause the ovary to make progesterone. Furthermore, the use of GnRH antagonists (Antagon, Cetrotide), which prevent premature ovulation in superovulation cycles, also reduce LH release for an extended period of time. If adequate progesterone is not made, then the lining of the uterus will not develop properly and there would be a greater risk of implantation failure or miscarriage.
Are there any recent studies that support the use of progesterone after insemination?
Yes. Erdem and colleagues published a study in Fertility and Sterility in 2009 that showed that clinical pregnancy rates and live birth rates were twice as high in women who used luteal progesterone support. Live birth rates per cycle were 17.4% in women who used vaginal progesterone as compared to 9.3 % in those who did not use any progesterone. Other studies have shown that pregnancy rates are higher when progesterone supplementation is provided whenever Cetrotide and Antagon are used.
Also See > Fertility Medications; Progesterone