Maternal blood mitochondrial DNA content during normal and intrauterine growth restricted (IUGR) pregnancy

We investigated mitochondrial DNA (mtDNA) content in the maternal circulation of normal pregnancies of different gestational ages and in pregnancies complicated by intrauterine growth restriction (IUGR). We examined 70 maternal blood samples: 13 nonpregnant women; 45 normal pregnancies, divided into the 3 trimesters; and 12 pregnancies complicated by IUGR. MtDNA content was determined by real-time quantitative polymerase chain reaction, using a genomic control and a target gene. A highly significant progressive reduction in circulating mtDNA was observed in pregnant women of first, second, and third trimesters and compared to nonpregnant women (mean value: 237, 188, 144, and 283, respectively; P <.001). Moreover, mtDNA was significantly increased in women carrying IUGR fetuses compared to women with normal pregnancies (430 vs 144; P <.001). MtDNA could provide new insight into the mechanisms that occur during physiological gestation. Furthermore, mtDNA content may help recognize the IUGR disease in pregnancy.