Pregnancy outcomes in women with chronic endometritis and recurrent pregnancy loss

To evaluate the prevalence of chronic endometritis (CE) in women with recurrent pregnancy loss (RPL) and compare pregnancy outcomes in women with and without CE.

Case-control observational study.

Academic fertility practice.

Women with two or more pregnancy losses.

Hematoxylin and eosin (H & E) staining was performed on all endometrial biopsies and plasma cells were identified by morphology. Immunohistochemical (IHC) staining for CD138 was later applied to all tissue samples. Charts were reviewed to evaluate the outcome of the next clinical intrauterine pregnancy.

Miscarriage rate and live birth rate.

A total of 107 women met inclusion criteria. The use of CD138 IHC staining resulted in a significantly higher prevalence of CE compared with the use of H & E staining and morphological assessment alone (56% [60/107] vs. 13% [14/107]). The 51 women with untreated CE were compared with the 45 women without CE by CD138 staining. Among those women with a subsequent pregnancy, the live birth rate in the next clinical intrauterine pregnancy after endometrial evaluation was 67.6% (23/34) in women with untreated CE and 87.1% (27/31) in women without CE. Age, body mass index (BMI), results of RPL evaluation, and number of prior losses were not significantly different between the two groups.

CD138 IHC staining of endometrial biopsies in women with RPL provides increased sensitivity when screening for CE compared with H & E staining and morphological assessment alone. Untreated CE may contribute to poor pregnancy outcomes and deserves further investigation in a larger cohort.