Reproductive characteristics of Southeast Asian immigrants before and after migration.

We describe the reproductive health and practices of Hmong immigrants before and after migration to the United States. Data were gathered as part of an ongoing study on the impact of perinatal exposure to environmental chemicals on children's health in Hmong residents of Green Bay, Wisconsin between August 1999 and May 2002. Of the 742 pregnancies reported by 141 reproductive-aged couples, 669 were live births. The Hmong have an average of 5.2 children (range 0-14) and the sex ratio differed by country of birth. Prenatal care began in the first trimester for 60% of US-born infants, up from 12% prior to immigration. Breastfeeding decreased from 94% and 88% in Laos and Thailand to only 11% for Hmong born in the US. Contraceptive use was reported by 25.5% of women; few reported smoking and alcohol consumption. The results suggest that Hmong immigrants may benefit from public health support targeting prenatal care and breastfeeding practices.