Risk of multiple sclerosis exacerbation during pregnancy and breast-feeding
L. M. Nelson, G. M. Franklin and M. C. Jones
Rocky Mountain Multiple Sclerosis Center, University of Colorado Health Sciences Center, Denver 80262.
Studies in the past have reported an increased risk of exacerbations in
multiple sclerosis during the postpartum period; it is not known whether
breast-feeding alters this risk. We interviewed 435 women regarding
pregnancy and breast-feeding history, providing for analysis 191
pregnancies that had occurred during a nonprogressive phase of the disease.
The exacerbation rates during the nine-month postpartum period (34%) were
more than three times the exacerbation rate during the nine months of
pregnancy (10%). The exacerbation risk was highest in the three-month
period following childbirth and appeared to stabilize after the sixth
postpartum month. The exacerbation rates in breast-feeding and
non-breast-feeding pregnancies were 38% and 31%, respectively. The average
time to exacerbation was similar in breast-feeding (3.0 months) and
non-breast-feeding (3.1 months) pregnancies. Although differential
exacerbation rates during pregnancy and the postpartum period may be
related to hormonal effects on the immune system, the hormonal effects of
breast-feeding do not appear to similarly affect the risk of exacerbation.
