Pregnancy has long been known to have a major impact on the developing breast and the future risk of breast cancer. Many studies have shown that hypertensive disorders of pregnancy (HDP) are associated with lower risk of breast cancer; and one major study has also demonstrated a significant reduction in risk of other types of cancer. Although this lower risk may be modest in the overall population of women who experience HDP, our recent research has shown that this reduction for breast cancer can be as high as 90% in a subgroup with HDP that carry a common variant in a key growth factor receptor gene (IGF1R). This study’s initial objectives are to reconfirm the above cancer associations, examine if the risk reduction extends to women with milder increases in blood pressure during pregnancy, and to examine whether these reductions are modified by other pregnancy factors such as prematurity, maternal age, or offspring gender.

Interestingly, HDP has also been shown to be associated with increased later life risk of hypertension and heart disease, indicating that experiencing HDP can have both good and bad long-term health outcomes. Therefore, a second objective is to further explore this association and determine if the same IGF1R gene variant that predicts breast cancer risk also predicts future risk of developing cardiovascular disease.

This study could improve the ability to predict future risk of developing the two most significant age-associated health outcomes that women face, thereby leading to more effective personalized screening and novel prevention strategies.