Association of LIN28B Gene Polymorphisms with Intrauterine Adhesions in Patients after Curettage Abortion.

Background/Objectives: Intrauterine adhesion (IUA) is characterized by endometrial fibrocyte hyperplasia. The LIN28B gene is associated with many proliferative diseases. However, its association with IUA is entirely unknown. We hypothesized that LIN28B gene polymorphisms are responsible for IUA susceptibility after curettage abortion. Methods: In this genetic association study, We genotyped two common polymorphisms (rs369065 C>T and rs314280 A>G) in 107 patients with IUA and 270 controls without IUA after curettage abortion from a Chinese population between July 2022 and May 2023 and analyzed their associations with IUA risk using multiple logistic regression models. Results: The carriers of genotype rs314280 AA of the LIN28B gene showed an increased risk of IUA (AOR [adjusted odds ratio] = 2.12, 95% CI [confidence interval] = 1.151-3.903), compared to GG+GA genotypes. Further stratification analyses showed that the deleterious role of the rs314280 AA genotype was more evident in patients with fewer than four pregnancies (AOR = 2.740, 95% CI = 1.355-5.540), fewer than two births (AOR = 2.676, 95% CI = 1.300-5.509), and fibrous (AOR = 2.082, 95% CI = 1.084-3.997) and muscular adhesions (AOR = 3.887, 95% CI = 1.116-13.540). However, the rs369065 T>C polymorphism of the LIN28B gene was not significantly associated with the occurrence of IUA. Conclusions: The rs314280 AA genotype of the LIN28B gene is associated with an increased risk of IUA in patients after curettage abortion, especially in those with fewer pregnancies or parities and higher disease severity. Our findings implicate a precise choice of clinical counseling and decision-making of IUA, thereby protecting female reproduction.