Contraception during cancer treatment
What is the safest method of contraception for people with cancer and their partners during cancer treatment?
Contraception during cancer treatment is an important component of ongoing management and requires careful consideration of individual patient factors, medical risks and comorbidities as well as effectiveness of contraceptive method and patient preference. The prevention of unplanned pregnancy during cancer treatment is essential to minimise risk and to avoid the potential for disruption of the treatment regimen. Furthermore, the risk of sexually transmitted infection is increased in patients with compromised immune systems. Protection of sexual partners from exposure to chemotherapy agents is also a consideration when recommending methods of contraception during treatment. Barrier methods including male and female condoms can help to prevent exposure to bodily fluids for sexual partners. There are, however, very few studies investigating the best method of contraception to use during cancer treatment.
The literature indicates that the patient experience is varied and health professional knowledge of appropriate contraceptives to recommend during cancer treatment could be improved. A systematic review of contraception recommended to the adolescent and young adults with cancer found that there were “no consistent recommendations among providers, references to guidelines, or methods of contraceptive types” (Fridgen 2017). A survey of medical oncologists found that only 20% informed patients that contraception is necessary before and during therapy (Guth 2016). A small qualitative study of oncology clinicians found that many lacked adequate education about appropriate contraception and there were inconsistent expectations as to which team member should assume primary responsibility for contraception counselling or referral. (Lindsay 2020).
Patient care may be compromised due to low levels of health professional education and protocols that do not include the discussion of contraception. A retrospective cohort study of 100 breast cancer patients younger than 40 years of age found that 62% of patients required contraceptive counselling, as either they weren’t using contraception, were using an ineffective method or an unsuitable method in the setting of breast cancer diagnosis (Guth 2016). Similarly, a cross-sectional survey of reproductive-aged women with cancer found that the use of contraceptive methods with high failure rates was common. In addition the study found that the provision of contraceptive counselling was positively associated with contraceptive use, particularly with the most efficacious methods. (Maslow 2014).
In 2012, the Society of Family Planning released clinical guidelines for cancer and contraception. It is not clear if a systematic approach was used to collate the references for this publication. The Society made a number of recommendations including that women with active cancer should avoid combined hormonal contraceptive methods due to the risk of deep vein thrombosis (DVT). There are also guidelines available on contraception for women with rare ovarian tumours. This guideline was developed using the DELPHI consensus process and also notes the risk of DVT for combined hormonal contraceptives (Rousset-Jablonski 2019).
The various contraceptive methods available confer variable medical risks, and there is a lack of studies available to quantify such risks for cancer patients specifically. Certain medical comorbidities present relative and absolute contraindications to certain contraceptive methods and this must be considered for all patients with cancer (WHO 2015). While long-acting reversible contraceptives (LARCs) generally provide the greatest contraceptive efficacy, their initiation risks, notably infection and bleeding, should be individualised to the person with cancer, with due consideration of any immune-comprised state. The well-documented risk of venous thrombo-embolism posed by the combined oral contraceptive pill (COCP) should be carefully considered for all women with cancer (SFP 2012).
Women with breast cancer and other hormonally sensitive cancers are a unique group, with COCP contraindicated and progestin-only contraceptives also not indicated, limiting their options to non-hormonal methods. The Society of Family Planning clinical guideline recommends the copper intrauterine device (c-IUD) as the first-line contraceptive option for women with breast cancer, on the basis of its high efficacy, long-acting, reversible and hormone free status. The progestin contraceptive injection should be avoided in patients with additional risk factors for osteopenia and osteoporosis (SFP 2012).
Menstrual suppression provided by contraceptive methods such as the levonorgestrel-containing intrauterine system (IUS) and other progestin contraceptives may be considered advantageous for patients with anaemia and/or at risk of bleeding while undergoing cancer treatments (SFP 2012). Natural family planning methods such as withdrawal, rhythm method and basal body temperature charting, may provide insufficient contraceptive efficacy for patients with cancer.
In summary, effective contraception is required during chemotherapy because of the medical risks associated with accidental pregnancy. There is, to date, no comprehensive guidance regarding contraception in this setting, and recommendations will differ according to the age of the woman, the type of cancer, and the type of cancer treatment.
Health professionals should discuss the need for contraception with cancer patients of reproductive age before,during and after cancer treatment.
A: Clinical question
B: Body of evidence
C: Literature search