Evaluation of an optimal luteal phase support protocol in IVF

Luteal phase support has been shown in the past to be an essential part of ovarian stimulation protocols, especially the long protocol. It could be shown that hCG is as effective as is progesterone for luteal phase support but hCG is accompanied by a higher rate of complications.

Progesterone can be administered in several routes. The oral, intramuscular (i.m.) and vaginal routes have been chosen frequently in the past. The oral route is ineffective, since progesterone has a low oral bioavailability (<10%), and a high rate of metabolites, which may result in side effects such as somnolence etc. Intramuscular administration provides very high serum levels of progesterone and this route is effective with regard to pregnancy rates. Injection of progesterone, however, is painful and cannot be done by the patient herself. The vaginal route is also effective, progesterone can be administered by the patient herself and progesterone is delivered directly to the uterus, where high levels are achieved (first uterine pass effect).

Several studies could show, in the past, that the vaginal administration of progesterone is effective also with regard to the downregulation of uterine contractions. Crinone 8% Vaginal Gel is especially designed for vaginal use with a special applicator and has to be administered once daily in the morning. It adheres to the vaginal epithelium, and leakage of the gel is substantially reduced as compared to other drugs like capsules or suppositories.

Since progesterone is as effective as hCG for luteal phase support but provides a higher safety with regard to ovarian hyperstimulation syndromes, and vaginal progesterone is as effective as intramuscular progesterone, vaginal progesterone should be the standard choice for luteal phase support. Crinone 8% seems to be the most comfortable way of vaginal administration of progesterone for luteal phase support in IVF cycles.