complications of the combined oral contraceptive pill
Last edited 03/2021 and last reviewed 07/2023
- increased mortality due to pulmonary embolism, cerebral thrombosis, myocardial infarction; smoking habit and age are the principal determinants:
- no excess mortality if non-smoker & < 35 years
- excess mortality of 10 per 100,000 woman years if smoker and < 35 years
- excess mortality of 15 per 100,000 if non-smoker and > 35 years
- excess mortality of 50 per 100,000 if smoker and > 35 years
- thromboembolism - oestrogen increases platelet count and adhesiveness, and reduces anti-thrombin; the low oestrogen content of modern combined pills has made deep vein thrombosis and pulmonary embolism rare, but progestogen only pills are advised if there is pre-existing heart disease
- metabolic - reduced glucose tolerance; increased levels of serum corticosteroid binding protein and thyroxine; progesterone increases LDL's and reduces HDL's, so increasing risk of stroke and myocardial infarction
- hypertension - increased release of hepatic renin precursors
- increased risk of gallbladder disease in susceptible patients
- cancer - effect on breast / cervical cancer. There is an association between use of the combined oral contraceptive and cervical cancer. The risk of breast cancer is described in the linked item
- menstruation - some women develop amenorrhoea, especially if cycles were previously irregular; no delay / acceleration of onset of menopause
oral contraceptives and cardiovascular (CV) risk
combined oral contraceptives and breast cancer risk
oral contraceptive (long term effects)