Obstetric complications in carriers of the m.3243A>G mutation, a retrospective cohort study on maternal and fetal outcome

Introduction: The mitochondrial DNA m.3243A. > G mutation is the most prevalent mutation causing mitochondrial disease in adult patients. Aside from some case reports, there are no studies on obstetric complications in a cohort of m.3243A > G carriers. We aimed to identify the prevalence of obstetric complications in a cohort of women carrying the m.3243A > G mutation. Methods: All female carriers of the m.3243A > G mutation known from our previous national inventory were sent a questionnaire regarding their obstetric history. Data were compared to national references. Data from the national inventory, including NMDAS (disease severity) scores and heteroplasmy levels in urinary epithelial cells (UEC) were used to stratify women. Results: Sixty women participated, the mean age was 47 years (range 20-70), mean NMDAS was 14.6 (range 0-46), and mean heteroplasmy percentage in UEC was 19.9% (range 5-85%). Ninety-eight pregnancies in 46 women were reported. Twenty-three (25.3%) had a premature delivery and five of them (5.5%) had a gestation of ≤ 32 weeks and eleven of the women (12%) suffered from preeclampsia. No different heteroplasmy level was found in the women with preeclampsia. Nine pregnancies (11%) were complicated by gestational diabetes. Discussion: Obstetric complications occur frequently in carriers of the m.3243A > G mutation. Proper guidance during pregnancies and early detection of possible obstetric complications are needed. As techniques to prevent transmission of mitochondrial mutations are studied it is important to know the possible complications patients may experience from the ensuing pregnancy.