Childbearing and Survival After Breast Carcinoma in Young Women

Background: Many young patients with breast carcinoma have not started, or completed, their desired families. How childbearing after a diagnosis of breast carcinoma affects survival is of importance to these women and their families. The authors measured relative mortality among young patients with breast carcinoma with and without births occurring after diagnosis.

Methods: The authors conducted a cohort study using data from three population-based cancer registries in the U.S. (Seattle, Detroit, and Los Angeles), linked to birth certificate data in each state. Four hundred thirty-eight women younger than 45 years of age with primary invasive breast carcinoma were identified as having births after diagnosis. In addition, 2775 comparison women, matched on the basis of age at the time of diagnosis, race/ethnicity, diagnosis year, disease stage, and presence of previous nonbreast primary tumors, were identified among those with breast carcinoma without births after diagnosis. Relative mortality was assessed using multivariable statistical methods.

Results: After adjustment for stage of disease, age at diagnosis, study region, diagnosis year, and race/ethnicity, women with births occurring 10 months or more after diagnosis had a significantly decreased risk of dying (relative Risk [RR] = 0.54, 95% confidence interval [CI], 0.41-0.71) compared to women without subsequent births. Women pregnant at the time of diagnosis had a mortality rate similar to those who did not give birth (RR = 1.10, 95% CI, 0.80-1.60).

Conclusions: The results of the current study, in light of growing evidence from other studies using various methods, may provide some reassurance to young women with breast carcinoma that subsequent childbearing is unlikely to increase their risk of mortality.