Neuroendocrine response to violence during pregnancy--impact on duration of pregnancy and fetal growth.

OBJECTIVE: To study the neuroendocrine release of cortisol in response to perceived stress among pregnant women exposed to partner violence and how this affects the duration of pregnancy and the intrauterine growth of the infant. DESIGN: Cross-sectional community-based study. SETTING: Health and Demographic Surveillance System of Leon, Nicaragua. POPULATION: One-hundred and forty-seven pregnant women. METHODS: Standardized scales to measure intimate partner violence, social resources, perceived stress, and socio-economic conditions were applied. Two salivary samples for cortisol were collected in the morning and afternoon on the same day. Linear regression and path analysis were used. MAIN OUTCOME MEASURES: Cortisol levels, gestational age, and weight at delivery. RESULTS: Partner violence during the pregnancy, low social resources, and perceived maternal stress were associated with high level of salivary cortisol. Pregnant women with high cortisol levels were significantly more likely to give birth to small-for-gestational age babies, but not to deliver preterm. A substantial decrease of birthweight, 121-186 g, was associated with an increase in cortisol in association with violence exposure. CONCLUSION: Partner violence during pregnancy is a stressor that provokes high levels of cortisol, which is associated with reduction of birthweight.