Mothers who breastfeed for 15 months or longer may be less likely to develop multiple sclerosis (MS) compared with those who breastfeed up to 4 months or do not breastfeed at all, according to a new study.
As women are twice as likely as men to develop MS, it is crucial to understand if aspects of motherhood is any way tied to the development of MS.
“This is another example of a benefit to the mother from breastfeeding,” says study author Annette Langer-Gould, MD, PhD, with Kaiser Permanente in the U.S.
“Other health benefits include a reduced risk of breast cancer, ovarian cancer, type 2 diabetes and heart attack.”
Women with Multiple sclerosis have significantly fewer relapses during pregnancy or while the child is nourished through breastfeeding only.
“Many experts have suggested that the levels of sex hormones are responsible for these findings, but we hypothesized that the lack of ovulation may play a role, so we wanted to see if having a longer time of breastfeeding or fewer total years when a woman is ovulating could be associated with the risk of MS,” Langer-Gould said.
For their study, the researchers recruited 397 women with an average age of 37. All of the women had recently been diagnosed with MS or with clinically isolated syndrome (CIS). CIS can eventually lead to the development of Multiple sclerosis.
The team compared the results of this group with the results of another group of 433 women who did not have MS. The researchers matched the healthy women for race and age with their counterparts.
The women were given in-person questionnaires about pregnancy period, breastfeeding, hormonal contraceptive use and other factors.
The team found that women who had breastfed for a cumulative amount with one or more children for 15 months or more were 53% less likely to develop MS or CIS than women who had not breastfed of breastfed for four months or less.
A total of 85 of the healthy female respondents had breastfed for 15 months or more, compared to 44 of the female respondents with MS. In contrast, 110 of the healthy women breastfed for zero to four months, compared to 118 of the women with MS.
The researchers also examined the lengths and histories of the participants’ menstrual cycles to see if ovulation held any relevance in the study results.
They found that women who were aged 15 or older at the time of their first menstrual cycle were 44% less likely to develop MS or CIS compared with females who had got their first period at age 11 or earlier.
Among the group of healthy women, 44 were 15 years or older at their first menstruation, compared with 27 women from the MS group. Also, 120 women from the healthy group were 11 years or younger at first menstruation than 131 women from the MS group.
The total number of years a female ovulated was not linked with risk of MS. Neither were other factors that would be part of that number, such as number of pregnancies, use of hormonal contraceptives and age at first birth.
Despite finding a correlation between breastfeeding for a long period and reduced risk of MS, the scientists warn against making any quick judgment. They insist that the correlation doesn’t imply causation.
Yet, they see the findings as a sign that mothers should be encouraged to breastfeed.
“This is another example of a benefit to the mother from breastfeeding,” says Dr. Langer-Gould.
The study also has its limitations. The women had to recall incidents that occurred several years ago, therefore there might be mistakes made by the participants. Additionally, reasons behind women’s breastfeeding, or for breastfeeding only for a limited period, were not looked into.
The study was published in the journal Neurology.