Giving working mothers paid maternity leave - and more of it - could go a long way toward helping them to continue breastfeeding their babies, a new study in Pediatrics shows.

“For breastfeeding it seems that really the time that matters is postpartum leave,” Dr. Sylvia Guendelman of the University of California at Berkeley, who led the research, told Reuters Health.

The American Academy of Pediatrics recommends that infants be breastfed exclusively for the first 6 months of life. But in 2002, while 72 percent of new moms in the US initiated breastfeeding, Guendelman and her colleagues point out in their report, just 35 percent were still nursing by the time their babies were 6 months old.

To investigate how work stressors and maternity leave time might influence their likelihood of breastfeeding success, the researchers interviewed 770 California women who had been working full-time before they had their babies. California is one of five states that provides 12 weeks of paid maternity leave, and an additional 6weeks “for infant bonding.”

Eighty-two percent of the women established breastfeeding, while 65 percent of these women were still nursing when the researchers interviewed them.

Sixty-eight percent of the women had returned to work by the time of the interview and half of these women were still breastfeeding.

The strongest predictor of whether a woman would continue breastfeeding was whether or not she returned to work within 6 weeks of delivery, the researchers found; those who did were 3.4 times more likely to stop breastfeeding than those who had longer leaves.

The risk of not establishing breastfeeding was also more than doubled among mothers who went back to work between 6 to 12 weeks after delivery compared to the women who were still not working.

Women who were managers, had flexible work schedules, and had more job autonomy were more likely to start breastfeeding their infants, and were more likely to breastfeed longer.

While the U.S. requires employers with 50 or more workers to offer them 12 weeks of unpaid, job-protected maternity leave, Guendelman and her team note, “many nonaffluent workers do not take leave because they cannot forego pay, are not covered, or are unaware of their eligibility, and that can be very stressful.”

The findings, they add, suggest that “merely establishing maternity leave policies without encouraging their use and making them economically feasible do not suffice to promote breastfeeding success.”

Canada recently extended its paid maternity leave from 6 months to 1 year, Guendelman noted in an interview. “Studies in Canada evaluating this policy are showing that breastfeeding increases by about one third of a month with every additional month that the mom is not at work,” she said.

SOURCE: Pediatrics, January 2009.