Association between birth defects and special risk exposures during peri-conception period

Objective: To analyze the effect of special risk exposures during periconception period on birth defects of newborns. Methods: From Jul. to Dec. 2013, the multi-stage stratified random sampling method was adopted. Women of childbearing age between 15 and 49 who were pregnant during 2010 to 2013 in Shaanxi Province were selected as study subjects for investigation on special risk factors exposed during periconception period. The Logistic regression model was adopted to analyze the association between newborns' birth defects and special risk exposures. Results: The study included 30 010 women of childbearing age and 29 550 newborns with 572 (193.57/10 000) cases of birth defects. After adjusting for demographic factors, the risk factors for birth defects were drinking [OR=2.29, 95% CI (1.22, 4.29)] and passive smoking [OR=1.25, 95% CI (1.02, 1.53)] during periconception. There was a higher risk of birth defects when exposure to medicine [OR=1.64, 95% CI (1.04, 2.61)], pesticides [OR=2.41, 95% CI (1.09, 5.35)], biological risk factors [OR=1.64, 95% CI (1.05, 2.56)], physical risk factors [OR=1.15, 95% CI (1.13, 2.34)] and chemical risk factors [OR=2.36, 95% CI (1.36, 4.11)] 3 months both before and after pregnancy. Similarly, after adjusting for demographic factors and behaviors, we found that birth defects were related to antibiotics, salicylates, and antitussive, which could increase the risk of birth defects (P<0.05). Conclusion: Exposure to passive smoking and drinking during periconception and exposure to medicines and pesticides, as well as biological, physical and chemical risk factors 3 months before and after pregnancy could increase the risk of birth defects in newborns.