Pablo Nepomnaschy and colleagues measured the levels of cortisol -- a stress-induced hormone -- in urine samples taken three times weekly for a year from 61 women in a rural Guatemalan community.

Nepomnaschy conducted the field work while a doctoral student at UM, both in the anthropology department and the school of natural resources and environment.

Cortisol Levels Linked to Very Early Miscarriage

The Guatemalan study is believed the first known to link increases in cortisol levels to very early stage pregnancy loss.

Most previous studies began when women noticed they were pregnant, about six weeks after conception. However, most miscarriages are known to occur during the first three weeks of pregnancy.

The only way to capture the first three weeks of pregnancy is to begin collecting [the female participant's] urine from before they become pregnant. That is extremely labor intensive and expensive, Nepomnaschy said.

He is now a post-doctoral fellow at the epidemiology branch of the National Institute of Environmental Health Sciences.