Side effects

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)

Reference:

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