Impact of Detection of Bacterial Endotoxin in Menstrual Effluent on the Pregnancy Rate in in Vitro Fertilization and Embryo Transfer

Objective: To examine whether bacterial endotoxin is detectable in menstrual effluent and to analyze a possible association between endotoxin levels and a pregnancy rate after IVF-ET.

Design: Prospective observational study.

Setting: University hospital.

Patient(s): Thirty-eight infertile women undergoing endotoxin assay and IVF-ET.

Intervention(s): Endotoxin was assayed by the limulus amoebocyte lysate test.

Main Outcome Measure(s): Levels of bacterial endotoxin and a pregnancy rate.

Result(s): In 38 samples of menstrual effluent taken from 38 women, bacterial endotoxin was detected with a range of 7.1 to >1,000 pg/mL in 37 samples and was not detected in 1 sample. After IVF-ET, pregnancy occurred in 9 of the 38 women. The mean (+/- SD) endotoxin level in these 9 pregnant women was 71.3 +/- 52.5 pg/mL and was significantly lower compared with >236.2 +/- 333.6 pg/mL in the 29 nonpregnant women. All pregnancies occurred in 28 women with an endotoxin level of </=200 pg/mL, whereas no pregnancies occurred in 10 women with an endotoxin level of >200 pg/mL, producing the significantly higher pregnancy rate in the former group than in the latter.

Conclusion(s): Bacterial endotoxin was detectable in menstrual effluent from infertile women. The pregnancy rate after IVF-ET was significantly higher in women with an endotoxin level of </=200 pg/mL than in women with an endotoxin level of >200.0 pg/mL.