LAUSR

BACKGROUND Multiple sclerosis (MS) predominantly onsets in women of reproductive age. The possibility of adverse obstetric and perinatal outcomes is a likely source of concern to pregnant women with MS and their clinicians. We aimed to compare the characteristics of the pregnancies of mothers with or without MS. METHODS The historical Oxford Record Linkage Study specialised maternity dataset (850,000 people, 1970-1989), with record-linkage between mother and baby, was analysed. The dataset was linked to any prior recorded day-case or inpatient hospital admission episodes back to 1963. The file of mothers' records was searched for a record of MS in either the maternity admission or in a previous admission. The pregnancies and babies of mothers with MS were compared with those of mothers without MS. RESULTS There were 181 pregnancies and babies born to 98 mothers with MS. These were compared with 244,573 pregnancies and babies of 124,830 mothers without MS. There was a significant social class gradient with a higher than expected number of cases of MS in the least deprived social classes. Mothers with MS tended to be lighter than other mothers. There were no significant associations between MS and mothers' marital status, history of smoking during the pregnancy, parity, pre-eclampsia, ABO blood group or rhesus group. There were no significant associations with babies' birth weight, and no significant associations with gestational age, being small for gestational age, Caesarian delivery, or forceps delivery. There were no stillbirths, no neonatal deaths, and no postneonatal deaths in the babies born to mothers with MS. CONCLUSIONS We hope that our findings will add to the available literature in addressing the understandable anxieties of young women with MS, and reassure them that the characteristics of their pregnancies are generally normal.