Estrogen receptor beta gene polymorphisms and risk of recurrent pregnancy loss: a case-control study

Estrogen might play a key role in the maintenance of pregnancy. We investigated the role of the ER- gene +1730G/A, +1082G/A, and CA repeat polymorphisms in Korean patients with recurrent pregnancy loss (RPL). Genotyping was performed using the TaqMan assay in 305 patients with at least two unexplained consecutive spontaneous miscarriages before 20 weeks of gestation and 299 controls. The genotype distributions of the ER- gene +1082G/A and +1730G/A polymorphisms in the RPL group did not differ from those in the control group. When the analysis was restricted to patients with three or more consecutive spontaneous miscarriages, there were also no differences in the genotype distribution between this subgroup and controls. The number of CA repeats was distributed from 13 to 28 with two large peaks at 18 and 23 in patients with RPL and controls. Using the two major peaks as cut-offs, the allele distributions were compared between patients and controls. However, the distribution of ER- gene CA repeats did not differ between women with recurrent miscarriage and controls. Findings of the current study suggest that the ER- gene polymorphisms are not major determinants of the development of RPL in Korean women.