Cervical cancer and duration of using hormonal contraceptives

Contemporary hormonal contraception and cervical cancer in women of reproductive age

To determine cervical cancer risk associated with contemporary hormonal contraceptives, we conducted a cohort study of women aged 15 to 49 living in Denmark from 1995 to 2014, using routinely collected information about redeemed prescriptions, incident cancer and potential confounders. Poisson regression calculated adjusted cervical cancer risks among different contraceptive user groups by duration of use, time since last use, hormonal content and cancer histology. During >20 million person-years, 3643 incident cervical cancers occurred. Ever users of any hormonal contraceptives compared to never users had a relative risk (RR) of 1.19 (95% confidence interval [CI] 1.10-1.29). Increased risks were seen in current or recent users of any hormonal: RR 1.30 (95% CI 1.20-1.42) and combined: RR 1.40 (95% CI 1.28-1.53), but not progestin-only contraception: RR 0.91 (95% CI 0.78-1.07). Current or recent users of any hormonal contraception had an increased risk of both adenocarcinoma (RR 1.29, 95% CI 1.05-1.60) and squamous cancer (RR 1.31, 95% CI 1.19-1.44). The risk pattern among any hormonal and combined contraceptive users generally increased with longer duration of use and declined after stopping, possibly taking longer to disappear among prolonged users. Combined products containing different progestins had similar risks. Approximately one extra cervical cancer occurred for every 14 700 women using combined contraceptives for 1 year. Most women in our study were not vaccinated against human papillomavirus (HPV) infections. Our findings reinforce the urgent need for global interventions such as systematic screening, treatment of cervical intraepithelial neoplasia and HPV vaccination programmes to prevent cervical cancer, especially among users of combined contraceptives.

Contraception in chronic kidney disease: a best practice position statement by the Kidney and Pregnancy Group of the Italian Society of Nephrology

Even though fertility is reduced, conception and delivery are possible in all stages of CKD. While successful planned pregnancies are increasing, an unwanted pregnancy may have long-lasting deleterious effects, hence the importance of birth control, an issue often disregarded in clinical practice. The evidence summarized in this position statement is mainly derived from the overall population, or other patient categories, in the lack of guidelines specifically addressed to CKD. Oestroprogestagents can be used in early, non-proteinuric CKD, excluding SLE and immunologic disorders, at high risk of thromboembolism and hypertension. Conversely, progestin only is generally safe and its main side effect is intramestrual spotting. Non-medicated intrauterine devices are a good alternative; their use needs to be carefully evaluated in patients at a high risk of pelvic infection, even though the degree of risk remains controversial. Barrier methods, relatively efficacious when correctly used, have few risks, and condoms are the only contraceptives that protect against sexually transmitted diseases. Surgical sterilization is rarely used also because of the risks surgery involves; it is not definitely contraindicated, and may be considered in selected cases. Emergency contraception with high-dose progestins or intrauterine devices is not contraindicated but should be avoided whenever possible, even if far preferable to abortion. Surgical abortion is invasive, but experience with medical abortion in CKD is still limited, especially in the late stages of the disease. In summary, personalized contraception is feasible, safe and should be offered to all CKD women of childbearing age who do not want to get pregnant.

Is oral contraceptive use associated with an increased risk of cervical cancer? An evidence-based meta-analysis

AIM

The purpose of this meta-analysis is to synthesize evidence-based case-control studies to evaluate the association between oral contraceptive (OC) use and the risk of cervical cancer.

METHODS

Two reviewers independently selected potentially relevant studies through PubMed, Embase, Chinese National Knowledge Infrastructure, Wanfang Data, and the Chongqing VIP databases using the core terms cervical intraepithelial neoplasia/ cervix dysplasia/ cervi* AND oral contraceptive in the article titles, abstracts, and keywords. All data were analyzed using stata 12.0. The heterogeneity was assessed by Q-test and I² statistic. Forest plot was used to display results graphically. Publication bias was assessed by Begg's test.

RESULTS

In total, 16 case-control studies, including 15 619 participants (7433 cases and 8186 controls), met the eligibility criteria. Individuals with OC use were not found to have a risk of cervical cancer (odds ratio [OR], 1.12; 95% confidence interval [CI], 0.90-1.38). In subgroup analyses, no significant associations were found for different durations of OC use (<5 years: OR, 0.84; 95%CI, 0.68-1.04; 5-10 years: OR, 1.06; 95%CI, 0.66-1.71; >10 years: OR, 1.25; 95%CI, 0.76-2.06). Additionally, using OC was not shown to increase the risk of cervical cancer among women with human papillomavirus infections (OR, 1.09; 95%CI, 0.80-1.49). However, an increased risk of cervical cancer was found in Asian populations with OC use.

CONCLUSION

The meta-analysis of case-control studies did not show an association between OC use and risk of cervical cancer. However, other necessary prospective cohort studies should be conducted to assess the impact of OC use on cervical cancer risk in the future.

Oral contraceptive use and risk of breast, cervical, colorectal, and endometrial cancers: a systematic review

Oral contraceptives may influence the risk of certain cancers. As part of the AHRQ Evidence Report, Oral Contraceptive Use for the Primary Prevention of Ovarian Cancer, we conducted a systematic review to estimate associations between oral contraceptive use and breast, cervical, colorectal, and endometrial cancer incidence. We searched PubMed, Embase, and Cochrane Database of Systematic Reviews. Study inclusion criteria were women taking oral contraceptives for contraception or ovarian cancer prevention; includes comparison group with no oral contraceptive use; study reports quantitative associations between oral contraceptive exposure and relevant cancers; controlled study or pooled patient-level meta-analyses; sample size for nonrandomized studies ≥100; peer-reviewed, English-language; published from January 1, 2000 forward. Random-effects meta-analyses were conducted by estimating pooled ORs with 95% confidence intervals (CIs). We included 44 breast, 12 cervical, 11 colorectal, and 9 endometrial cancers studies. Breast cancer incidence was slightly but significantly increased in users (OR, 1.08; CI, 1.00-1.17); results show a higher risk associated with more recent use of oral contraceptives. Risk of cervical cancer was increased with duration of oral contraceptive use in women with human papillomavirus infection; heterogeneity prevented meta-analysis. Colorectal cancer (OR, 0.86; CI, 0.79-0.95) and endometrial cancer incidences (OR, 0.57; CI, 0.43-0.77) were significantly reduced by oral contraceptive use. Compared with never use, ever use of oral contraceptives is significantly associated with decreases in colorectal and endometrial cancers and increases in breast cancers. Although elevated breast cancer risk was small, relatively high incidence of breast cancers means that oral contraceptives may contribute to a substantial number of cases.