PALO ALTO, Calif., Feb. 25 -- Breastfeeding may reduce a woman's risk of having a relapse of multiple sclerosis after giving birth, researchers here said.
Nearly 90% of women with multiple sclerosis who didn't breastfeed exclusively had a postpartum relapse. That was more than twice the relapse rate among MS mothers who did breastfeed, Annette Langer-Gould, M.D., of Stanford University Medical Center, and colleagues reported in an abstract scheduled for release at the American Academy of Neurology meeting in April.
About 60% of the women said their primary reason for not breastfeeding was to resume MS treatments. "Our findings call into question the benefit of choosing not to breastfeed or stopping breastfeeding early in order to start taking multiple sclerosis therapies," Dr. Langer-Gould said.
She said the protective effect of breastfeeding may be the suppression of menses that results from intensive nursing. This has an anti-inflammatory effect and suppresses immune cells that attack the central nervous system, she said.
On average, patients with multiple sclerosis have one relapse every two to three years, Dr. Langer-Gould said.
To determine whether exclusive breastfeeding reduces the risk of postpartum relapses, the researchers conducted a prospective trial of 32 pregnant women with the disease and 29 healthy pregnant age-matched control subjects.
They found that 52% of the women with multiple sclerosis did not breastfeed or began regular supplemental feedings within two months postpartum. Of those, 87% relapsed, compared with 36% of women with multiple sclerosis who breastfed exclusively for at least two months (HR 7.1, 95% CI 2.1 to 24.3, P=0.002).
Women who didn't breastfeed exclusively and resumed their multiple sclerosis therapies within the first two months after giving birth had a significantly higher risk of relapse than women with the disease who did not restart their medications early (P<0.001).>
Dr. Langer-Gould said that the high relapse rate among women who didn't breastfeed could be explained by two factors: they don't get the protective anti-inflammatory effects of immune system suppression brought on by halted menses, and most multiple sclerosis medications take four to six months to take full effect.
So if women start treatments at two months postpartum, they lack both forms of protection, Dr. Langer-Gould said.
"It's a small study so the results still need to be replicated," she added. "But for women with multiple sclerosis who want to nurse and create that bond with their child, there is no evidence that exclusive breastfeeding is harmful to them."
Primary source: American Academy of Neurology
Langer-Gould A, et al "Exclusive breastfeeding and the risk of postpartum relapses in women with multiple sclerosis" AAN