Risks and benefits of using the oral contraceptive pill


What are the risks?

1. Blood clots

  • A personal history of VTE (blood clots) or a known thrombogenic mutation (genetic problems that increase your risk of forming blood clots) are conditions that represent an unacceptable health risk if CHC is used.
  • For women with a family history of VTE, a negative thrombophilia screen does not necessarily exclude all thrombogenic mutations and a thrombophilia screen is not recommended routinely before prescribing CHC.
  • The UKMEC classifies having a first-degree relative with a history of VTE under the age of 45 years as a UKMEC 3(risk outweights benefits).

2. Smokers

  • Use of CHC in women aged ≥35 years who smoke is not recommended.

3. Risk of ischaemic stroke

  • Health professionals should be aware that there may be a very small increase in the absolute risk of ischaemic stroke associated with CHC use.

4. Blood pressure

  • Systolic BP ≥160 mmHg or diastolic BP ≥95 mmHg is a condition that represents an unacceptable health risk if CHC is used.

5. Obesity

  • The risk of using CHC in women with a BMI ≥35kg/m2 usually outweighs the benefits.

6. Migraine

  • CHC should not be used in women with migraine with aura.

7.Breast cancer

  • Any risk of breast cancer associated with CHC use is likely to be small, and will reduce with time after stopping.
  • A family history of breast cancer therefore does not restrict use of CHC (UKMEC 1).


What are the benefits of using Combined Hormonal Contraceptives?


  • Reduced risk of ovarian and endometrial cancer that continues for several decades after stopping.


  • May help to improve acne.


  • COC use is associated with a reduction in the risk of colorectal cancer and this may also apply to other CHCs.


  • May help to reduce menstrual pain and bleeding.


  • May reduce menopausal symptoms.


  • Current evidence does not support a causal association between CHC and weight gain.