Über die Morphologie der menschlichen Placenta mit besonderer Rücksicht auf unsere eigenen Studien

Remarkable placenta

This paper reviews the principle features of human placenta structure and development, and it highlights areas of needed future research. The complexity of placental histology is discussed and comparison of the human placenta with other mammalian taxa is made. A more widespread appreciation of the value of studying this challenging organ and a more profound understanding of the regulation of the placental transport functions is advocated. Simple, routine examination of the placenta should be resurrected.

The site of umbilical cord insertion and birth weight

The site of the insertion of the umbilical cord into the placenta was determined in 940 consecutive term infants. No relation was found between birth weight and whether the cord was inserted centrally, eccentrically or marginally.

Congenital absence of the heart: observation of human funiculopagous twinning with insertio funiculi furcata, fusion, forking, and interpositio velamentosa

An anatomic and radiologic study of a normal and acardius twinning with a single placenta is presented with literature review. The fetus was unusually well-developed with an almost normal skeletal and brain formation, a normal genito-urinary tract, and an absence of liver, spleen, lungs, and pancreas. The heart was absent but the great arteries, single aorta, and veins were present. The placentation is described as funiculopagous with insertio funiculi furcata, fusion, forking and interpositio velamentosa, and the latter may account for the fusion of the two circulations in this instance with the possibility that the heart was never present. The present and other observations of funiculopagous twins with two amniotic sacs suggest that the forked cord twin anomaly may occur earlier than generally recognized.

Bibliography on prenatal and natal influences in twins

The author agrees with earlier writers that most of the differences observed in monozygotic pairs are due to unusual or extreme environmental factors acting before or during the twins' birth. Although they are typical of development in twins, these environmental factors can hardly be considered typical of development in other individuals. This point, as a review of the literature shows, is often overlooked by those who study twins in the childhood or adult age ranges. As a result the inferences drawn from twin differences are frequently mistaken, or at least quite exaggerated so far as the significance of postnatal influences in non-twins is concerned. At the same tihe, if allowance is made for the environmental biases peculiar to twin studies, the findings may be said to establish more about the importance of heredity in the medical and behavior sciences than most investigators have thought. In the author's opinion the largest single source of bias is the mutual circulation that exists during prenatal development of the majority of monozygotic pairs. Data on that circulation's difference-producing effects are reviewed and related to studies of mature twins. Effects of lateral inversions (asymmetry reversals) and of “natal” factors (chiefly conditions of delivery) are also reviewed, and methods of judging the importance of all three of the biasing conditions are outlined. Need for obtaining systematic and complete information about the natal factors is stressed.

Foamy changes of placental cells in fetal storage disorders

Vacuolar cytoplasm in placental cells was observed in four cases. In each instance the baby was either stillborn or died soon after birth. One infant was shown to have Inclusion cell disease (Mucolipidosis II), whereas in the other cases biochemical studies were noncontributory or could not be carried out. The histologic changes of the placenta described in this report were restricted to the fetal elements and also included the X cells, providing further evidence that these cells are of fetal rather than maternal origin.