Placenta: The Shape of Things to Come
Could unusual configurations forecast health problems?
Normal placentas are round or oval. Sometimes, though, blood vessels branch in unusual ways, changing the organ’s shape. In animal models, these abnormal growth patterns have been linked to a variety of maternal stresses, and pathologist Carolyn Salafia, founder of the independent research group Placental Analytics, thinks studying the shapes of human placentas immediately after birth can reveal the stage of pregnancy at which things went awry. That, in turn, might predict later problems for a child.
One study of pregnant sheep found that such factors as over- or underfeeding, excessive heat and carrying multiple fetuses directly affected the growth of placental blood vessels. Some of these stresses suppressed growth, while others accelerated it. Salafia thinks that even common environmental events during human pregnancies—such as a mother’s taking particular medications—may have a similar impact, molding the placenta into one of many abnormal shapes.
Experiments with a statistical model that University of Toronto mathematics professor Michael Yampolsky developed support Salafia’s hypothesis that the timing of gestational trouble correlates with particular placental shapes. Problems at the end of the first trimester, for instance, led to placentas with spikelike protrusions.
The findings are intriguing in the context of other research. For example, there is evidence linking autism to a maternal rubella infection at the end of the first trimester. Salafia’s model suggests that a large-scale study searching for correlations between autism and star-shaped placentas could make or break that theory. Other research has shown that specific characteristics of placental shape and size may indicate which children would develop high blood pressure within their first decade of life. Unraveling these complex associations may help scientists understand the mechanisms that lead to negative health outcomes.