Objective: To investigate in the natural cycle just before IVF, whether glycodelin levels in endometrial flushing fluid obtained days LH+1 and LH+7 can be used in predicting pregnancy in the following IVF cycle, and whether there are differences in women with tubal factor infertility compared to women with unexplained infertility and fertile controls.

Study design: A prospective observational multicentre study of 21 fertile and 75 infertile women (25 showed abnormal tubes with no signs of hydrosalpinges, 18 had uni- or bi-lateral hydrosalpinges, 17 were salpingectomised because of hydrosalpinges, and 15 women had unexplained infertility). Endometrial flushing at days LH+1 and LH+7, endometrial biopsy, and blood sampling at day LH+7 were performed before down-regulation for IVF. Glycodelin levels in endometrial flushing fluids (EFF), biopsies, and plasma samples were related to tubal pathology, endometrial dating and IVF outcome. Furthermore, total protein concentration was measured in EFF to investigate the influence of normal endometrial maturation on protein concentrations from days LH+1 and LH+7.

Results: At day LH+1, EFF glycodelin levels were higher in infertile women with abnormal tubes compared to fertile women, particularly in women conceiving after the following IVF. For women with unexplained infertility, a higher level at day LH+1 was present only in women not conceiving after the following IVF. ROC curve analysis showed that at day LH+1 EFF glycodelin levels had no predictive value for IVF outcome. At day LH+7, glycodelin levels in endometrial flushing fluids and biopsies depended on endometrial dating.

Conclusions: At day LH+1, glycodelin concentration is increased in endometrial flushing fluid from infertile women with abnormal tubes compared to fertile controls without being a valuable predictor of subsequent pregnancy. At day LH+7 the glycodelin level depends on endometrial dating.