DEOXYRIBONUCLEIC-ACID, RIBONUCLEIC-ACID, AND PROTEIN IN THE PLACENTASOF 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 d eoxyribonucleic acid (DNA), ribonucleic acid (RNA), and protein,conten t. The mothers of the infants all had prepregnancy weights within +/- 15 percent expected body weight for body frame, according to the Metro politan 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 w ere analyzed along with the placenta from six mothers with insulin dep endent 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 severe ly growth retarded (asymmetric) infants. The placenta from the infants of diabetic pregnancies contained DNA and RNA in amounts similar to t hat found in normal pregnancy placenta but the protein content was gre ater.