Women who did not plan to get pregnant are much more likely to stop breastfeeding within three months of giving birth, according to a study published in the journal Current Anthropology. The research suggests that women whose pregnancies were unplanned often experience more emotional and physical discomfort with breastfeeding compared to women who planned to get pregnant.

More than 40 percent of the women in the study, which focused on mothers from low-income neighborhoods in São Paulo, Brazil, had stopped exclusively breastfeeding by three months, despite the fact that all of the women had intended to breastfeed for at least that long. The World Health Organization and the Brazilian government recommend that women should breastfeed exclusively at least for a baby's first six months.

Older women and women who were less satisfied in their relationships with partners and family breastfed exclusively for shorter periods, the research found. But by far the strongest predictor of shorter breastfeeding duration was unplanned pregnancy. "Women who had a baby after an unplanned pregnancy were ten times as likely to regularly feed the baby foods other than breast milk by 12 weeks compared to women whose pregnancies were planned," said Alanna Rudzik, an anthropologist at Durham University in the U.K. and the study's author.

Previous research has uncovered broad social and demographic factors that influence breastfeeding, such as income, education, and employment, Rudzik says. But her study combined quantitative methods with up to seven in-depth interviews with each of the women in the study to get at the personal experiences that influenced her breastfeeding decisions. Women in the study were interviewed once before giving birth, and every two weeks afterward until the 12 week mark.

"The ethnographic data revealed that the negative feelings that women have about unplanned pregnancy likewise incline them to strongly ambivalent feelings towards breastfeeding," Rudzik said. "The interviews showed that women who had not planned to become pregnant had difficulty accepting their new role as a mother, and this expressed itself in part through strong resistance to the extremely close physical connection required by breastfeeding."

This resistance came through in the way that women spoke about breastfeeding. Women who had unplanned pregnancies were more likely to talk about the physicality of breastfeeding as being unpleasant or difficult. Rudzik quoted one participant as saying "when you're breastfeeding her you feel her there sucking, the milk coming out. Ah, it's horrible." And another as saying, "I feed, feed, feed, and she sucks, sucks, sucks, and she still wants more! She only stops crying to open her mouth [to breastfeed]."

In contrast, Rudzik writes, women with planned pregnancies "embraced full breastfeeding as the epitome of maternal love and sacrifice" as it is usually presented in Brazilian clinics. "Notably they reveled in the physicality of the connection between themselves and their infants."

"I think the strongest bond is during breastfeeding, né?" said one mother. "It's very good. It's a moment between you and her, né? It's very good having someone there sucking your milk."

These differences suggest that "resistance to unplanned motherhood and to the physicality of breastfeeding may be an important determinant of women's decisions about how to feed their babies," Rudzik concludes.

Rudzik hopes her insight into women's subjective experiences might offer a practical guide to organizations that promote breastfeeding. Rates of unplanned pregnancy are extremely high in the area where the research was conducted, and have been shown to be related to structural inequities in education, income and employment. "Sensitizing health workers to the internal pressures faced by women who experience unplanned pregnancy provides on important way to improve breastfeeding promotional programs," she writes.

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More information: Alanna Rudzik, "The Experience and Determinants of First-Time Breast-Feeding Duration among Low-Income Women from São Paulo, Brazil." Current Anthropology 52:1 (February 2012).