A new study shows a correlation between nausea and vomiting during pregnancy and the long-term neurocognitive development of those kids. Pediatric researcher Irena Nulman and her team at the Hospital for Sick Children in Toronto found that youngsters whose mothers suffered from morning sickness during pregnancy scored higher on some cognitive tests than did those whose mothers did not start their pregnant days throwing up. All children tested within the normal range, however.

One possible explanation could be differing hormone levels, Nulman says. According to one hypothesis, vomiting reduces caloric intake, decreasing insulin secretion. Low insulin, in turn, boosts levels of other hormones that are known to play a role in the de­velopment of a healthy placenta and a healthy blood supply to growing brains.