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

<b><i>Background/Objectives</i></b>: Intrauterine adhesion (IUA) is characterized by endometrial fibrocyte hyperplasia. The <i>LIN28B</i> gene is associated with many proliferative diseases. However, its association with IUA is entirely unknown. We hypothesized that <i>LIN28B</i> gene polymorphisms are responsible for IUA susceptibility after curettage abortion. <b><i>Methods</i></b>: 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. <b><i>Results</i></b>: The carriers of genotype rs314280 AA of the <i>LIN28B</i> 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 <i>LIN28B</i> gene was not significantly associated with the occurrence of IUA. <b><i>Conclusions</i></b>: The rs314280 AA genotype of the <i>LIN28B</i> 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.