Analysis of the risk factors in patients with unexplained recurrent spontaneous abortion.

Abstract

We aimed to explore the risk factors in patients with unexplained recurrent spontaneous abortion (URSA) and to provide a basis for clinically targeted therapy. This case-control study comprised 202 patients with URSA treated at our hospital and 115 women in early pregnancy with a normal birth history during the same period. After procuring the data we conducted a multivariate logistic regression analysis of risk factors related to URSA. Logistic regression analysis showed (i) that the number of spontaneous abortions (SAs; odds ratio [OR]=492.123), the levels of autoantibodies (OR=19.322) and tumor necrosis factor alpha (TNF-α; OR=9.615), and the CT and TT genotypes of methylenetetrahydrofolate reductase (MTHFR) C677T (OR=6.217 and 15.009, respectively) were risk factors for URSA and (ii) that 25-hydroxyvitamin D (25-(OH)D; OR=0.919) was a protective factor. The most important risk factor was a history of one or more SAs, with the risk of pregnancy loss increasing 491.123-fold. Every unit increase in serum 25-(OH)D reduced the risk of SA by 8.1%. The risk factors for URSA included the number of SAs, the levels of autoantibodies and TNF-α, and the MTHFR C677T T allele; 25-(OH)D was a protective factor. We recommend that women diagnosed with URSA receive intervention as soon as possible so as to actively reduce the incidence of recurrent SA.