Objective To survey and identify the preterm-related social and behavioral risk factors, so as to provide evidence to adopt efficient and comprehensive prevention and control measures.

Methods A case-control study was designed. Mothers with preterm infants and full-term infants were randomly sampled in two hospitals in Guilin and were interviewed with questionnaires on their demographic information, residential environment, social relationship, life style, as well as status of health and reproduction. Non-conditional logistic regression model was used to calculate the OR values for preterm outcome given various potential risk factors.

Results A total of 111 cases and 117 controls were recruited in the study. Age, behavior, social relationship, abortion history, and clinical conditions were the influencing factors of preterm. In terms of social relationship, good interpersonal and marriage relationships were protective factors of preterm, with the OR values (95%CI) of 0.28 (0.17-0.63) and 0.62 (0.34-0.86) respectively. Behaviors including exposure to passive smoking and staying up late, older age, and poor clinical health conditions such as induced abortion, premature rupture of membrane, multifetation, and anemia were the risk factors of preterm, especially passive smoking exposure and multifetation were closely associated with preterm, with OR values (95%CI) of 9.58 (2.54-33.83) and 9.12 (8.32-13.62) respectively.

Conclusion Good marriage and interpersonal relationships could decrease the risk of preterm; in the contrary, bad behaviors including passive smoking exposure and staying up late, poor clinical health conditions, and older gestational age could increase the risk of preterm.