Objective: To investigate overall, spontaneous, and medically indicated preterm birth (PTB) rates between US-born and non-US-born Asian women living in California.
Study design: Nulliparous women with a singleton livebirth and Asian race in California between 2007 and 2011 were investigated. The prevalence of overall (<37 weeks), spontaneous, and medically indicated PTB was examined by self-reported race and place of birth among ten Asian subgroups.
Results: There were marked differences in PTB rates between the individual Asian subgroups. After adjustments, non-US-born Chinese, Japanese, Vietnamese, and Indian women had lower odds of overall PTB and Chinese, Vietnamese, Cambodian, and Indian women had lower odds of spontaneous PTB compared with their US-born counterparts.
Conclusion: Further investigation of biological and social factors contributing to these lower odds of spontaneous PTB among the non-US-born Asian population could potentially offer clues for reducing the burden of PTB among the US born.