Mitochondrial Myopathy, Encephalomyopathy, Lactic Acidosis, Stroke-like Episodes Syndrome

INTRODUCTION: The purpose of this study was to systematically review the literature on pregnancy outcomes in women with MELAS syndrome, one of the commonest mitochondrial disorders, and summarize strategies for their preconceptional, antepartum and intrapartum care. METHODS: MEDLINE, EMBASE, Web of Science, and PubMed were searched from inception to January 2016 for publications describing pregnancies with MELAS syndrome. Studies were only restricted to humans. The grey literature and references of relevant articles were hand-searched. Authors were contacted for missing data or eligibility inquiries. Article selection, data extraction and risk of bias assessment were performed in duplicate with discrepancies resolved by a third reviewer. Articles were excluded if MELAS syndrome was not confirmed or pregnancy outcomes were not described. RESULTS: Of 1412 identified titles and abstracts, 53 full texts were retrieved; 12 case reports were retained for final analysis, including one from our institution. In 2/12 (17%) cases, MELAS syndrome was diagnosed in pregnancy. Up to 11/12 (91%) women experienced severe maternal or obstetric complications such as admission to the intensive care unit, stroke-like episodes, or hypertensive disorders of pregnancy. Adverse fetal or neonatal outcomes, such as pregnancy loss or intrauterine growth restriction, were seen in 8/16 (50%) and 4/11 (36%) pregnancies respectively. Adverse outcomes occurred even when women were in complete remission pre-pregnancy. There were no maternal or neonatal deaths. CONCLUSION: MELAS syndrome is a multi-organ disorder associated with significant adverse medical and obstetric outcomes. Patients with this diagnosis should have preconception counseling and multidisciplinary pregnancy management in a tertiary center to optimize outcomes.