Background:There is a paucity of information on maternal multiple sclerosis (MS) and
risk of adverse pregnancy and perinatal outcomes.Objective:The aim of this study was to determine the association between MS and risks
of adverse pregnancy and perinatal outcomes in women with MS. In women with
MS, the influence of exposure to disease-modifying therapy (DMT) was also
investigated.Methods:Population-based retrospective cohort study on singleton births to mothers
with MS and matched MS-free mothers from the general population in Sweden
between 2006 and 2020. Women with MS were identified through Swedish health
care registries, with MS onset before child’s birth.Results:Of 29,568 births included, 3418 births were to 2310 mothers with MS. Compared
with MS-free controls, maternal MS was associated with increased risks of
elective caesarean sections, instrumental delivery, maternal infection and
antepartum haemorrhage/ placental abruption. Compared with offspring of
MS-free women, neonates of mothers with MS were at increased risks of
medically indicated preterm birth and being born small for gestational age.
DMT exposure was not associated with increased risks of malformations.Conclusions:While maternal MS was associated with a small increased risk of few adverse
pregnancy and neonatal outcomes, DMT exposure close to pregnancy was not
associated with major adverse outcomes.