OBJECTIVETo investigate the possible risk factors of congenital malformations in cities of Guangxi.

METHODSA case-control study was carried out on 281 cases of congenital malformations and 730 controls. Analysis of simple factor and multiple factors unconditional logistic regression were done.

RESULTSThe analysis of simple factor and multiple factors showed that main risk factors of congenital malformations as multiple pregnancies (OR = 2.6), pregnancy complications (OR = 3.2), exposure to chemical substances before or during pregnancy (OR = 3.0), taking sedatives (OR = 10.2), hormone drug (OR = 9.4) or Chinese herbal medicines (OR = 2.5) during the early stage of pregnancy, mothers' blood type as AB (OR = 3.5) or A (OR = 2.2), mothers' emotion being nervous and melancholy (OR = 2.6), mothers' occupation being workers (OR = 3.8) or peasants (OR = 3.0), fathers' exposure to noise (OR = 5.7) or suffering from chronic diseases (OR = 2.8).

CONCLUSIONSSome risk factors were identified as having important effect on perinatal congenital malformations, including taking sedatives, hormone drug or Chinese herbal medicines during the early stage of pregnancy, mothers' emotion being nervous and melancholy, multiple pregnancies, pregnancy complications, exposure to chemical substances before or during pregnancies, mothers' blood type as AB or A, mothers' occupation being workers or peasants, fathers' exposure to noise or suffering from chronic diseases.