The site of umbilical cord insertion and birth weight

Sonographic prenatal diagnosis of marginal placental cord insertion: clinical importance

OBJECTIVE

To assess the impact of a sonographic diagnosis of marginal placental cord insertion on birth weight and duration of pregnancy.

METHODS

A retrospective chart review was performed for 100 singleton pregnancies with prospectively identified marginal placental cord insertion.

RESULTS

Birth weights below the 10th percentile occurred in 6.25% of pregnancies without preeclampsia. Spontaneous preterm delivery occurred in 7.3% of pregnancies without preeclampsia. Rates of birth weight below the 10th percentile and preterm delivery were not significantly different from those in the general population. Preeclampsia developed in 4 patients; all had elective preterm deliveries, and all gave birth to neonates with birth weights below the 10th percentile.

CONCLUSIONS

A prenatal diagnosis of marginal placental cord insertion is not associated with increased risk of growth impairment or preterm delivery.

A contemporary view of the human placenta

Our current knowledge of the human placenta is briefly reviewed. Particular stress is placed upon the considerable functional reserve capacity of the placenta, the unimportance of most visible abnormalities of the placenta, the lack of any evidence that the placenta ages during gestation and the lack of significance of placental weight. The effects on the placenta of infection and of maternal cigarette smoking are considered and the concept of placental insufficiency critically discussed. It is concluded that most cases of 'placental insufficiency' are, in reality, examples of maternal vascular insufficiency resulting from inadequate placentation during the early stages of pregnancy.

Invited review. A contemporary approach to placental pathology

A brief description is given of the significance of gross and histological abnormalities of the placenta. The question of placental ageing is discussed and the possible ill-effects of inflammation and immune-mediated damage to the placenta considered. Finally, the pathology of the utero-placental vasculature is outlined, and the view is expressed that most cases of apparent 'placental insufficiency' are, in reality, due to maternal vascular insufficiency.