Noncontraceptive Benefits

Many contraceptive methods have health effects beyond pregnancy prevention. These benefits are significant in practice: they provide the main reason some patients use a method, they influence method choice in patients with menstrual or endocrine disorders, and they must be balanced against each method's risks. They support counselling but do not replace specific treatment where one is indicated.

Principles.

• Match the method to the patient's priorities, including treatment of menstrual or endocrine problems.

• Quote benefits accurately; do not exaggerate protective effects.

• State the risks of each method alongside the benefits.

• Persisting or severe conditions need diagnosis and specific treatment, not only a contraceptive.

Benefits by method.

Cancer risk. Combined pill use for 5 years or more lowers ovarian and endometrial cancer risk by about 30 to 50 percent, with benefit lasting 15 years or more after stopping. Current use of combined pills is associated with a small increase in breast cancer risk (relative risk about 1.2) that returns to baseline within about 10 years of stopping, and cervical cancer risk rises with use over 5 years in HPV-infected women.

Contraceptives are not first-line cancer prevention. The cancer risk change should be mentioned in counselling but should not be the reason for starting a method in a patient who does not need contraception.

Using benefits to choose a method.

• Heavy menstrual bleeding: levonorgestrel 52 mg IUD first, then combined pills, with tranexamic acid 1 g orally three times daily for 4 days for acute control.

• Dysmenorrhoea: combined pills (extended regimen if needed), levonorgestrel IUD, or implants, with an NSAID.

• Acne and hirsutism: combined pills with low androgenicity progestogen, such as cyproterone acetate 2 mg with ethinylestradiol 35 micrograms, or drospirenone 3 mg with ethinylestradiol 20 to 30 micrograms; effect takes 3 to 6 months.

• Premenstrual dysphoric disorder: drospirenone 3 mg with ethinylestradiol 20 micrograms in a 24 active and 4 inactive pill regimen.

• Endometriosis: continuous combined pills, dienogest 2 mg orally daily, or levonorgestrel IUD.

• Polycystic ovary syndrome: combined pills for cycle control and endometrial protection; a progestogen-only method provides endometrial protection when oestrogen is contraindicated.

• Sickle cell disease: DMPA or other progestogen-only methods; combined pills only when no vascular disease.

• Endometrial protection with hormone therapy or tamoxifen: levonorgestrel IUD.

• Anaemia: methods that reduce menstrual loss.

Counselling on risk. Tell patients the matching risks: VTE with combined methods, bone density loss with DMPA (largely reversible), spotting with progestin-only methods, heavier periods with copper IUD.

Common errors.

• Treating persistent abnormal bleeding with a contraceptive without investigating the cause.

• Prescribing combined methods for acne or dysmenorrhoea in patients with migraine with aura, hypertension, smoking at age 35 or over, or VTE risk.

• Presenting cancer protection as a reason to take the pill indefinitely.

• Ignoring the VTE risk with cyproterone acetate and drospirenone products.

Special groups. Adolescents with dysmenorrhoea or heavy bleeding benefit from combined pills or progestin-only methods after exclusion of bleeding disorders. Perimenopausal patients may benefit from a levonorgestrel IUD for heavy bleeding and from combined methods for vasomotor symptoms when eligible.

Referral and escalation. Refer for abnormal uterine bleeding unresponsive to treatment, suspected endometrial hyperplasia or cancer, suspected endometriosis not controlled by first-line treatment, and suspected bleeding disorders.