From Womb to Womb

Carl Zimmer in his excellent blog, The Loom:

Worldwide, women suffer an estimated 2.65 million stillbirths each year. Despite those huge numbers, we only understand some of the factors that are responsible. In low- and middle-income countries (where most of the world’s stillbirths occur), diseases like malaria can put pregnant women at risk of stillbirths. In wealthier countries, the biggest risks include smoking and obesity. But these factors only go partway to explaining why some women have stillbirths, leaving many cases unaccounted for. The benefits that would come from that knowledge could be enormous.

One way to learn about reproductive health is to observe how our primate cousins have babies. And a new study on marmosets offers some hints about the causes of stillbirth. It suggests that a mother’s health during pregnant may not be the whole story. In fact, some of the risk factors may arise before mothers are even born.

The first thing that one notices about the white-tufted ear marmoset (Callithrix jacchus) is its wildly adorable face–a tiny visage framed by shocks of white fur. Marmosets are interesting to scientists not because they’re cute, but because of theirintriguing way of having kids. While most primate females have a single offspring at a time, marmoset typically have twins. Some marmoset mothers even have triplets.

This is a tricky strategy for passing on marmoset genes. Marmoset babies can weigh between a fifth and a quarter of their mother’s weight. Imagine a 135-pound woman giving birth to two 16 pound babies–and then nursing them.

More here.