Deoxyribonucleic acid, ribonucleic acid, and protein in the placentas of normal and selected complicated pregnancies

Placenta from uncomplicated term pregnancies resulting in the birth of male infants weighing between 2900 and 3800 grams were analyzed for deoxyribonucleic acid (DNA), ribonucleic acid (RNA), and protein content. The mothers of the infants all had pre-pregnancy weights within +/- 15 percent expected body weight for body frame, according to the Metropolitan Life Tables. There were no significant differences, as regards the content of DNA, RNA and protein, between the placental cotyledons. Nine placenta from mothers giving birth to growth retarded infants were analyzed along with the placenta from six mothers with insulin dependent diabetes mellitus. A trend suggesting less DNA in the placenta of the severely growth retarded (symmetric) infants when compared with placenta from the normal pregnancies was not noted in the less severely growth retarded (asymmetric) infants. The placenta from the infants of diabetic pregnancies contained DNA and RNA in amounts similar to that found in normal pregnancy placenta but the protein content was greater.