Unintended births among adult immigrant and U.S.-born Mexican women in the Los Angeles Mommy and Baby (LAMB) survey.

BACKGROUND: Unintended births are especially frequent among minority women. Predictors of unintended births among adult Mexican women living in the United States are poorly characterized.

METHODS: Data are from vital statistics and the 2005 Los Angeles Mommy and Baby (LAMB) survey, a population-based study of women delivering a live birth in Los Angeles County, California (n = 1,214). Multivariable logistic regression assessed the relation of unintended birth with acculturation variables adjusting for background and psychosocial characteristics. Multinomial models assessed these relations for women with an unintended birth who did and did not use contraception.

FINDINGS: Forty-one percent of women reported an unintended birth. Being a long-term immigrant and U.S.-born were positively associated with unintended birth compared with shorter term immigrants, but the adjusted relation was significant only for U.S.-born women (odds ratio [OR], 2.01; 95% CI, 1.19-3.39). Women reporting an unintended birth were younger, unmarried, and higher parity. If using contraception, the odds of unintended birth were increased for cohabiting women, those with high education, and those with greater stress during pregnancy. When not using contraception and reporting an unintended birth, women also have no usual place for health care, have depressive symptoms during pregnancy, and are dissatisfied with partner support.

CONCLUSIONS: Women's background and psychosocial characteristics were central to explaining unintended birth among immigrant women but less so for U.S.-born Mexican mothers. Interventions to improve birth intentions should not only target effective contraception, but also important social determinants.