Growth of the fetus and placenta of the monkey (Macaca mulatta)

Abstract

The weight and length of fetal monkeys, Macaca mulatta, from the fortieth day of gestation to term were tabulated and plotted as growth curves. Also plotted were the weight of the normal placenta, the area of the placenta and the weight of the placenta when retained in the absence of the fetus. Fewer data were available for the length of the umbilical cord and volume of amniotic fiuid.The records were drawn from 343 pregnancies following a known date of insemination and in each case the pregnancy was without complication such as illness of the mother or discernible defect in embryo, fetus or newborn. The average length of 225 gestations ending with a spontaneous birth of a live infant was 168 ± 7 days.The macaque colony from which this material was derived has been described (van Wagenen, '50).