Meta-analysis of oral contraceptive use and risks of all-cause and cause-specific death.
BACKGROUND
Whether ever use of oral contraceptives (OCs) is associated with mortality remains unclear.


OBJECTIVE
To evaluate the association between ever use of OCs and mortality.


METHODS
On November 2, 2014, PubMed and Embase were searched for human studies, using the terms "contraceptive," "contraceptives," "death," and "mortality."


METHODS
Prospective cohort studies were included that provided risk estimates on OC use and mortality, and were reported in English or Chinese.


METHODS
A random-effects model was used to pool data. Random-effects meta-regression was used to determine whether duration of OC use and time since last OC use were associated with mortality.


RESULTS
Nine studies were included. Ever use of OCs was not associated with mortality from all causes (hazard ratio [HR] 0.94; 95% CI 0.87-1.02) or breast cancer (HR 1.00; 95% CI 0.95-1.06). Neither the duration of OC use nor the time since last OC use was associated with all-cause or breast cancer mortality. In an analysis of a small number of studies, ever users were at decreased risk of mortality from ovarian cancer (HR 0.58; 95% CI 0.35-0.94).


CONCLUSIONS
There is no significant association between ever use of OCs and mortality from all causes or breast cancer.
Department of Hepatobiliary Surgery, The Second Affiliated Hospital of Chongqing Medical University, Chongqing 40010, China. Electronic address: gczhong1991@163.com.
Guo-Chao
GC
Zhong
Department of Urinary Surgery, The Second Affiliated Hospital of Chongqing Medical University, Chongqing 40010, China.
Jia-Hao
JH
Cheng
Department of Urinary Surgery, The Second Affiliated Hospital of Chongqing Medical University, Chongqing 40010, China.
Xiang-Long
XL
Xu
Department of Urinary Surgery, The Second Affiliated Hospital of Chongqing Medical University, Chongqing 40010, China.
Kang
K
Wang
D001943:Breast Neoplasms / Q000453:epidemiology / Q000401:mortality*; D002423:Cause of Death; D003276:Contraceptives, Oral / Q000009:adverse effects*; D005260:Female; D006801:Humans; D009026:Mortality
D003276:Contraceptives, Oral
Breast cancer; Meta-analysis; Mortality; Oral contraceptives