Use of Contraception by Women with Breast Cancer

Clinicians caring for reproductive-aged women with a history of breast cancer are faced with complex clinical decisions about contraception safety and effectiveness, in addition to possible risks from an unplanned pregnancy. A retrospective study was conducted in Kaiser Permanente, Northern California from 2006-2007 on 449,181 reproductive age women. Evidence of contraception and counseling (contraception and preconception) was captured through electronic data from clinical and pharmacy databases. Women with breast cancer (931) were compared to women with other chronic medical conditions (OCMC=24,184) and to women without any chronic medical conditions (“healthy”=122,921). A detailed chart review was included for 240 randomly selected women without evidence of contraception or counseling. Highly effective contraception (primarily permanent sterilization) was used by 26.0% of women with breast cancer compared to 22.3% of OCMC women and 10.6% of “healthy” women (breast cancer vs healthy p=<0.001; breast cancer vs OCMC p=0.02). Reversible contraception was found in 11.8% (intrauterine contraception [IUC]: 7.6%) of women with breast cancer compared to 40.7% (IUC: 6.5%) of healthy women (p-value <0.001: reversible contraception; p=0.18 for IUC). The chart review found 12.5% of women with breast cancer using abstinence compared to 13% for OCMC and 0% for “healthy” women. Many women with breast cancer, OCMC and “healthy”, had no database documentation of contraception (62% breast cancer vs. 49% OCMC vs, 38% “healthy”, p<0.001). A significant proportion of women with breast cancer used reversible contraception. IUC was their primary form of reversible contraception, with similar rates to those used by healthy women.