Patterns of luteal phase bleeding in in vitro fertilization cycles supplemented with Crinone vaginal gel and with intramuscular progesterone--impact of luteal estrogen: prospective, randomized study and post hoc analysis.

OBJECTIVE: To compare patterns of luteal phase bleeding (LPB) in IVF cycles supplemented with Crinone and with intramuscular progesterone (IMP) and to evaluate the impact of luteal estrogen supplementation on LPB.

DESIGN: Prospective, randomized trial and post hoc analysis.

SETTING: University-affiliated IVF unit.

PATIENT(S): Women under age 40 with day 3 FSH <15 mIU/mL were randomized to receive either Crinone or IMP for luteal phase support. Luteal estrogen was prescribed according to clinical protocols. Three hundred sixty-five patients were queried about LPB after completion of their IVF cycles.

INTERVENTION(S): Luteal phase supplementation with Crinone or IMP and with estrogen.

MAIN OUTCOME MEASURE(S): Incidence of LPB in IVF cycles supplemented with Crinone and IMP and impact of luteal estrogen on the occurrence of LPB.

RESULT(S): There was no difference in the overall incidence of LPB between patients treated with Crinone and those treated with IMP (33.2% vs. 25.7%). LPB occurred with equal frequency among pregnant patients in both arms (Crinone 21.9% vs. IMP 18.6%). Only nonpregnant women had a higher incidence of LPB when treated with Crinone compared with treatment with IMP (56.5% vs.38.1%). Estrogen supplementation decreased the occurrence of LPB among all participants but did not impact pregnancy rates.

CONCLUSION(S): Only nonpregnant women had a higher incidence of bleeding in the luteal phase when supplemented with Crinone compared with treatment with IMP. IMP delays menses in nonpregnant cycles without affecting pregnancy rates. Luteal estrogen decreases LPB without impacting cycle outcomes.