side effects

Last reviewed 03/2021

Those associated with oestrogen may include:

  • weight gain*, fluid retention
  • headache
  • nausea and vomiting
  • increased menstrual flow
  • venous thrombosis
  • increased cervical secretion / cervical erosion

Those associated with progestogen may include:

  • breast fullness
  • decreased libido, dry vagina
  • reduced menstrual flow, disturbance in menstrual cycle
  • acne
  • premenstrual depression

There is a higher incidence of adenocarcinoma of the cervix in women taking oral contraceptives especially if they are taken for longer than 12 years.

* although changes in body weight are stated as possible side effects when using a combined pill (1), a systematic review concluded that available evidence was insufficient to determine the effect of combination contraceptives on weight, but no large effect was evident (2)


  1. BNF 7.3.1
  2. Gallo MF et al. Combination contraceptives: effects on weight. Cochrane Database Syst Rev 2006;(2):CD004002