Umbilical Cord Pathology

Exploring the impact of HIV infection and antiretroviral therapy on placenta morphology

INTRODUCTION

Women living with HIV experience more adverse birth outcomes; the mechanisms are not fully understood. We examined placenta morphology and associations with birth outcomes in a Canadian cohort of women living with HIV (HIV⁺) on antiretroviral therapy (ART) from conception and HIV-uninfected (HIV^-) women.

METHODS

Term placentas from 94 women (40 HIV^-, 54 HIV⁺) were studied. Trimmed placenta weight was collected. Placenta digital photos were used to compute morphometric parameters. Regression models investigated associations between log-transformed placenta parameters and birth outcomes.

RESULTS

We observed a trend towards lower placenta weight and smaller placenta area in the HIV⁺ group, both of which were significantly associated with small for gestational age births. HIV⁺ serostatus was associated with 6-fold (95%CI 2-20) greater odds of having placenta area in the lowest quartile (<236 cm²). Cord marginality (distance from the edge) was significantly lower in the HIV⁺ group (p = 0.004), with 35% of placenta having an abnormal (marginal or velamentous) cord insertion vs. 12.5% in the HIV^- group (p = 0.01). Velamentous cord insertion was seen in 13% of placentas in the HIV⁺ vs. 0% in HIV^- group (p = 0.02). A significant correlation between cord marginality and placenta thickness was observed in the HIV^- group, with a more marginal cord being associated with a thicker placenta. This correlation was not observed in the HIV⁺ group. HIV⁺ placentas exposed to protease inhibitors were significantly less circular compared to the HIV^- group (p = 0.03).

CONCLUSION

Our data suggest that HIV/ART exposure affects placenta morphology and is associated with higher rates of abnormal cord insertion.

Umbilical cord hypercoiling in two rhesus macaques (Macaca mulatta)

Obstruction of umbilical blood flow is a common cause of death in fetal nonhuman primates, but cord accidents have not been reported in the macaque. We describe two cases of cord accident in rhesus macaques (Macaca mulatta) resulting in fetal death at approximately 110 and 50 days of gestation, respectively.

Forensic Aspects of Perinatal Deaths

From a forensic pathologist's perspective, there are several aspects of the perinatal postmortem that are particularly important. If a fetus is found abandoned, the pathologist needs to ascertain the fetal age, the appropriateness of growth, if the baby was born alive or dead, and the possible causes of death. In cases of litigation for perinatal deaths occurring in hospitals, access to the obstetric and neonatal notes (if the baby is born alive and dies a few hours or days later) is fundamental to reach a correct interpretation and conclusion. The most important points to consider in cases of intrapartum death are the roles of asphyxia and trauma in the causation of the baby's death. Timing of the fetal death in relation to delivery may also be an important point in these cases. Finally, intrapartum lesions should always be considered in the differential diagnosis of possible child abuse in babies aged two months or less.