Unintended Pregnancy Linked to Unhealthy Maternal Behaviors

First published online:

Two-fifths of live births to Maryland women between 2001 and 2006 followed unintended pregnancies, and women whose pregnancies were unintended were more likely than those who had intended to conceive to engage in a number of unhealthy behaviors before, during and after the pregnancy.1 In surveys completed 2–9 months postpartum, women reporting a mistimed or unwanted pregnancy had increased odds of saying that they had not used folic acid daily before conception, that they had smoked during pregnancy or since delivery, and that they suffered from postpartum depression. They were less likely than other mothers to have begun prenatal care during the first trimester and to have breast-fed for at least eight weeks.

The surveys were conducted as part of the Pregnancy Risk Assessment Monitoring System. Each year, participating states mail a random sample of postpartum women a questionnaire that asks about their pregnancy intentions and maternal behaviors. Data are weighted to be made representative of all women in the state who had live births during the year and are linked with birth certificate data, which provide demographic, medical and pregnancy information. Analysts used bivariate and logistic regression methods to identify associations between selected maternal behaviors and pregnancy intendedness among women in Maryland.

During the study period, 41% of Maryland women who had a live birth had not intended to conceive when they did: Thirty-one percent had wanted to become pregnant at a later time, and 10% had not intended ever to become pregnant. The proportion of pregnancies that were unintended varied significantly by women's socioeconomic characteristics. It was markedly higher among black mothers, teenagers, women with no more than a high school education, Medicaid enrollees and unmarried women than among others.

The analysts examined reports of one preconception behavior (daily use of folic acid), four prenatal behaviors (cigarette smoking and alcohol consumption in the third trimester, receipt of prenatal care in the first trimester and receipt of no prenatal care) and six postpartum behaviors (smoking, any breast-feeding, breast-feeding for at least eight weeks, placing the infant on his or her back to sleep, depression and contraceptive use). Results of bivariate analyses suggest that women whose pregnancies had been mistimed or unwanted were generally less likely to engage in healthy behaviors than were those who had intended to conceive. For example, 55–67% of women with unintended pregnancies had begun receiving prenatal care during the first tri-mester, compared with 86% of those whose pregnancies had been planned; 12–23% and 8%, respectively, had smoked during the third trimester. The exceptions to this pattern were that third-trimester alcohol consumption was more common, and postpartum contraceptive practice was less common, among women who had had intended pregnancies than among others.

Findings from multivariate analyses confirm that unintended pregnancies are associated with relatively unhealthy maternal behaviors. Compared with mothers who had intended to conceive, those whose pregnancies had occurred earlier than they would have liked were more likely not to have used folic acid daily before conceiving (odds ratio, 2.2) and more likely to experience postpartum depression (1.3); they were less likely to have begun prenatal care early (0.5). Women who had not wished to conceive at any time had elevated odds of not using folic acid daily before pregnancy (2.3), smoking while pregnant and after giving birth (2.1 and 1.9), and reporting postpartum depression (2.0); they had reduced odds of saying that they had begun prenatal care during the first trimester (0.3) and that they had breast-fed for eight weeks or longer (0.7).

In discussing the limitations of their study, the analysts observe that the postpartum period is not "the ideal time to ascertain pregnancy intention" and that, in any case, "the definition of unintended pregnancy…is innately problematic." Nevertheless, they conclude, the survey data demonstrate that unwanted pregnancies that end in live births are associated with a variety of unhealthy perinatal behaviors. Prevention of unintended pregnancies should help to reduce the prevalence of these behaviors, they note, adding that primary care and family planning service providers can play a role by including discussions of healthy behaviors in their visits with women of reproductive age.

—D. Hollander


1. Cheng D et al., Unintended pregnancy and associated maternal preconception, prenatal and postpartum behaviors, Contraception, 2009, 79(3):194–198.