Increased incidence of obstetric complications in women carrying mitochondrial DNA mutations: a retrospective cohort study in a single tertiary centre.

OBJECTIVE:To investigate the obstetric outcome of women carriers of the oxidative phosphorylation (OXPHOS) disorder mutation. DESIGN:A retrospective cohort study in a single tertiary centre. SETTING:A review of the obstetric history of women referred for prenatal screening of a mitochondrial disorder was performed. POPULATION:Women were divided into three groups: (1) women carrying mitochondrial DNA (mtDNA) mutations; (2) healthy women with a family history of mtDNA-related OXPHOS disorder; and (3) healthy women carrying heterozygote nuclear DNA mutations. METHODS:Obstetric history and pregnancy complications were evaluated separately in the three groups and compared with the control group. MAIN OUTCOME MEASURES PREGNANCY COMPLICATIONS. RESULTS:Seventy-five women were included with 287 cumulative pregnancies. Groups 1 and 3 had a significantly greater proportion of terminations of pregnancy (20 and 13% versus 0.8%, P < 0.001), and a lower percentage of live births (52 and 72% versus 87%, P = 0.001), compared with controls. Apart from this, the rate of obstetric complications in group 3 did not differ from the controls. The obstetric history of women in group 1 was marked by higher rates of early miscarriages (26 versus 11%, P = 0.004), gestational diabetes (14 versus 3%, P = 0.02), intrauterine growth restriction (IUGR, 10 versus 1%, P = 0.008), and postpartum haemorrhage than were reported for controls (12 versus 2%, P = 0.01). CONCLUSION:Women who are heteroplasmic for OXPHOS mutations have a higher incidence of pregnancy losses, gestational diabetes, IUGR, and post postpartum haemorrhage. TWEETABLE ABSTRACT:Women heteroplasmic for mitochondrial DNA mutations have a higher incidence of obstetric complications, compared with the control group.