Clinical Studies on Biometrics of the Placenta

ABSTRACT

With increasing concern for the study of the fetal aspects of pregnancy and child-birth the availability of normal standards becomes more and more important. It is very difficult to test the functional capacity of the placenta, and for this reason anatomic studies to determine the normal relationship between the placenta and the newborn infant have come to be of considerable importance. Three hundred seventy eight placentas randomly collected in the past three years and ranged of the twenty-fourth gestation week to term which were delivered at Severance Hospital of Yonsei Medical College. These were analysed statistically as to whether there was any correlation between the size of the placentas, weight of newborn, and age and parity of the mother and were studied to see if there was any clinical and statistical significance in the change of the placental coefficients. We have also tried to search for any relationship between the specific gravity and the size of the placenta and the newborn weight. In addition to these factors, clinical complications such as toxemia, anemia, intrauterine fetal death, giant baby and infarction of the placentas were included in this study to seek any relationship with the above mentioned factors. Another purpose was to obtain the proper values for Korean placentas. We have summarized this study briefly as follows. 1. The average weight of the 378 newborns was 3l68 gm and for the 340 normal cases it was 3270 gm. 2. The average weight of 378 placentas was 6l6 gm and for the 340 normal cases it was 621 gm. 3. The average volume of 378 placentas was 588 cc and for normal cases it was 596 cc. 4. The average placental dimensions were 17.9 X 14.2cm. 5. The average surface area of the 340 norma1 cases was 276 cm2. 6. The specific gravity of 340 normal cases was 1.0475 and there was no relationship to the gestation weeks and baby weight. 7. The average placental coefficient of 378 cases was 0.194 and for 340 normal cases it was 0.190 (varying from 0.100 to 0.333). The placental coefficients were greater in toxemia syphilis, intrauterine fetal death, prematurity twin pregnancy and immaturity. However it was lower in placental infarction and in relatively small placentas. In anemia and giant baby it was close to the normal average but in extremely large baby placenta coefficients was greater than Normal averages. (Baby wt. > 4500gm. ). 8. The weight of baby and the size of the placenta showed no demonstrable relationship to the age and parity of the mother. 9. statistically there was a high correlation between the weight of the infants and the weigh of the infants and the weight and volume of the placenta but somewhat low relationship to the surface area of the placenta.