Morning sickness could indicate low breast cancer risk
Women who suffer from morning sickness while pregnant may have a 30% lower risk of later developing breast cancer than women who remain nausea-free, research shows.
Scientists are not sure of the exact mechanisms responsible for pregnancy nausea, but suggest it may result from changing levels of human chorionic gonadotrophin hormone, which may also protect against cancer.
"Pregnancy is a time of drastic physiological changes, including rapid development and alterationg in the breast tissue," says lead study author, David Jaworowicz.
"The rapidly changing anatomy of the breast makes it more susceptible to errors in DNA replication and or repair, which may translate into breast cancer."
The scientists compared the pregnancies of 1,001 women with primary breast cancer with those of 1,917 women without breast cancer.
They found that as nausea symptoms worsened or if they persisted for longer, women's risk of developing breast cancer reduced.
Jaworowicz says future studies will investigate the potential association between pregnancy characteristics and genetic polymorphisms of particular enzymes responsible for estrogen metabolism.
"This will help us to elucidate the potential link between pregnancy-associated conditions, hormonal exposure and breast cancer risk," he concludes.