DOI: 10.1111/aji.13774 ISSN:

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

Ming‐Ming Li, Jie Lin, Hai‐Fan Wu, Guo‐Jun Zheng, Ruo‐Nan Cai
  • Obstetrics and Gynecology
  • Reproductive Medicine
  • Immunology
  • Immunology and Allergy
  • Obstetrics and Gynecology
  • Immunology



We aimed to explore the risk factors in patients with unexplained recurrent spontaneous abortion (URSA) and to provide a basis for clinically targeted therapy.

Method of study

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.

More from our Archive