Bleeding patterns in women using intramuscular progesterone for luteal support in in-vitro fertilisation cycles

This paper aims to evaluate the effects of i.m. progesterone on bleeding patterns after in-vitro fertilisation embryo transfer (IVF-ET). It is a retrospective cohort study conducted in the reproductive endocrinology and IVF department of a teaching hospital. One hundred consecutive women were studied who had undergone IVF-ET using 'long protocol' stimulation with leuprolide acetate-recombinant follicle stimulating hormone (rFSH) and who did not become pregnant. Intramuscular (i.m.) progesterone (50mg once daily) was started the day before oocyte retrieval and continued for a minimum of 12-14 days following embryo transfer. The main outcome measures were time interval between oocyte retrieval and onset of bleeding, luteal phase serum progesterone and oestradiol (E2) levels, and midluteal endometrial thickness. Of the 100 patients whose charts were reviewed, 67 bled (group A) before progesterone treatment was discontinued (17 days after oocyte retrieval) and 33 (group B) bled after progesterone treatment was discontinued (> 17 days). Mean onset of bleeding was 16.2+/-2.6 days after oocyte retrieval. Serum progesterone concentrations were similar in the two groups on the day of hCG administration, whereas progesterone concentrations (in-group B) were higher on days 7 and 15 after oocyte retrieval. No statistically significant differences were found between two groups with respect to mean midluteal endometrial thickness and mean serum E2 concentrations on days 0, 7 and 15. The results suggest that i.m progesterone administration for luteal support in assisted reproduction cycles elongates luteal phase in some patients due to supraphysiological serum progesterone levels. However, most patients start to bleed in the absence of pregnancy despite continued progesterone treatment.