Placental site nodules and reproductive outcomes: a clinicopathologic case series.

Background: Placental site nodules (PSNs) are benign tumor-like growths that develop from chorionic-type intermediate trophoblastic cells. Their clinical significance is unknown. This study aims to determine the risk factors associated with PSNs, with focus on possible reproductive impact.

Methods: We performed a retrospective case series of all patients with a pathology diagnosis of PSN in a large urban hospital system from 2018 to 2022. We collected clinical variables such as pathology diagnosis/description, presenting symptoms, method of prior delivery, and prior history of infertility, pregnancy loss, and uterine instrumentation.

Results: A total of 32 patients were included in this case series. The most common presenting symptom was abnormal uterine bleeding (40.6%, 13/32). Recurrent pregnancy loss (RPL) (15.6%, 5/32) and infertility (15.6%, 5/32) were common presenting symptoms as well. 62.5% (20/32) patients had a history of prior uterine instrumentation. Coexisting chronic endometritis was identified in 9.4% (3/32) of cases. Of the 5 RPL/infertility patients who underwent hysteroscopic resection of a PSN, 1 achieved a live birth.

Conclusion: PSNs may be associated with abnormal uterine bleeding, recurrent pregnancy loss, infertility, history of prior uterine instrumentation, and chronic endometritis. Although a rare diagnosis, the presence of a PSN should be considered in patients presenting for infertility or recurrent pregnancy loss workup.