Neonatal Outcome in Pregnancies with Autoimmune Myasthenia Gravis

Pregnancy outcomes for women with myasthenia gravis and their newborns: A nationwide register-based cohort study

BACKGROUND AND PURPOSE

Few large-scale studies examine whether maternal myasthenia gravis (MG) is a risk factor for complications during pregnancy and childbirth. This study evaluated whether maternal MG is associated with an increased risk of adverse pregnancy, delivery, and neonatal outcomes.

METHODS

We conducted a nationwide Swedish register-based cohort study of women who gave birth to singleton infants (≥22 gestational weeks) during 1987-2019. Exposed women were diagnosed with MG before or during the index pregnancy (N = 443). Unexposed women comprised 4249 women without a diagnosis of MG, matched for age, parity, hospital, and year of childbirth. The risks of adverse pregnancy, delivery, and neonatal outcomes for women with MG were estimated using regression modeling and presented as adjusted odds ratios (aOR).

RESULTS

There was no increased risk of pregnancy complications in women with MG. Women with MG had a spontaneous onset of labor less often than women without MG (69.8% vs. 79.5%; aOR 0.59; p < 0.001) as well as higher labor induction rates and elective cesarean section deliveries (16.0% vs. 12.3%, aOR 1.42; p = 0.02 and 12.0% vs. 8.1%, aOR 1.59; p = 0.009). Infants of women with MG were born on average 2 days earlier (p = 0.002); however, these infants did not have a higher risk of having low APGAR, being small for gestational age, or having a congenital malformation.

CONCLUSION

This first nationwide study of pregnancy in women with MG in Sweden demonstrates reassuring results overall, suggesting generally safe pregnancy outcomes for women with MG and their infants.

Transient neonatal myasthenia gravis: refining risk estimate for infants born to women with myasthenia gravis

OBJECTIVE

Transient neonatal myasthenia gravis (TNMG) can render a neonate vulnerable to catastrophic respiratory depression. Our aim was to describe the clinical manifestations of TNMG, and to determine when the myasthenic signs become apparent in TNMG.

METHODS

We reviewed our own experience of infants who underwent routine inpatient monitoring for TNMG and combined our local data with observations from previous studies.

RESULTS

Only three case series (n = 110) reported both the type and timing of onset of myasthenic signs. Adding local data (n = 37) yielded 147 infants born to women with MG. Fifteen infants (10%) developed signs of TNMG with onset being 1.5 ± 2.6 days (mean ± 3SD) after birth. Feeding difficulties and low tone were the commonest presenting signs, and only 1 of the 147 infants needed intubation for hypoventilation.

CONCLUSIONS

TNMG signs were mostly not life-threatening. We suggest only 4 days of routine postnatal observation for infants born to women with MG.

Neuromuscular Diseases of the Newborn

The peripheral nervous system (PNS) is composed of motor neurons, nerve roots, plexuses, peripheral nerves (motor, sensory and autonomic), neuromuscular junction, and skeletal muscles. Disorders of the PNS in neonates most frequently cause weakness, hypotonia, and contractures, which may be generalized or focal. Since these findings may also occur with brain and spinal cord lesions, key features of the history and neurologic exam, together with diagnostic testing, are helpful in reaching a diagnosis. This review covers the diagnostic approach to PNS disorders in the neonate and includes a discussion of representative diseases of the motor neuron, brachial plexus, peripheral nerves, neuromuscular junction, and muscles. The importance of reaching a precise genetic diagnosis is highlighted with a discussion of current and emerging treatments for neonatal PNS diseases, particularly spinal muscular atrophy.

Myasthenia gravis and pregnancy: retrospective evaluation of 27 pregnancies in a tertiary center and comparison with previous studies

BACKGROUND AND AIM

To share our experience with the management of pregnancies in women with myasthenia gravis (MG) in a tertiary center.

METHODS

The study retrospectively evaluated 27 pregnancies in 12 patients. The pregnancies were divided into 3 groups on the basis of the clinical course of MG during pregnancy: improvement (n = 7), disease-stable (n = 9), and deterioration (n = 11). The groups were compared with respect to patient characteristics, clinical features, and obstetric outcomes.

RESULTS

There were 4 miscarriages (14.8%), 3 preterm births (11.1%), and 4 cases of preterm premature rupture of the membranes (PPROM) (14.8%). Exacerbation was observed in 25.9% of the cases; the remission rate during the postpartum period and after miscarriage was 37%. The cesarean section (CS) rate was 78.3%. Pregnancies with deterioration of MG were statistically more likely to have higher miscarriage, preterm birth, PPROM, CS, and transient neonatal MG rates, in addition to a lower gestational age at birth, birth weight, and 5-min Apgar score than pregnancies with improved or stable disease (p values < 0.001, 0.04, 0.03, 0.009, 0.02, < 0.001, 0.002, and 0.043, respectively).

CONCLUSION

Physicians who manage pregnant women with MG must be familiar with the clinical features of the condition; a multidisciplinary approach is necessary for a better prognosis.

Intravenous immunoglobulin as monotherapy for myasthenia gravis during pregnancy

INTRODUCTION

Pregnant women with myasthenia gravis (MG) are at increased risk of complications and adverse outcomes, including the teratogenic effects of many drugs used to treat MG women of childbearing age. The effectiveness of intravenous immunoglobulins (IVIg) on other autoimmune mediated diseases has been extensively reported in recent years, although little is known about the role of IVIg in the treatment of MG during pregnancy. We designed this study to determine the effectiveness of IVIg as monotherapy during pregnancy for women with MG.

MATERIAL AND METHODS

Five pregnant MG patients (mean age at delivery 36.4years, SD 5.8, range 29.4-45.2) were studied in 2013-14. Their treatment was switched to monthly IVIg cycles 2months before the pregnancy. Follow-up included monthly neurological QMG throughout the pregnancy and postpartum, obstetrical monitoring during monthly visits in the first two trimesters of the pregnancy, fortnightly visits between week 32 and week 36, and weekly visits after 36weeks, and neonatal follow-up after delivery.

RESULTS

We observed no exacerbations during pregnancy, delivery or post-partum. The mean QMG score at baseline (before pregnancy) was 7.4 points in five women with generalized forms of MG. The maximum mean value reached during pregnancy was 8.6 points. The mean pregnancy duration was 38 w+5 d. No infant with transient neonatal myasthenia gravis.

CONCLUSIONS

These results suggest that monotherapy with IVIg during pregnancy in MG patients could be promising, although confirmation is required in studies with larger populations.