Makindo Medical Notes

The Combined Oral Contraceptive Pill (COCP) is a widely used form of birth control that contains two hormones: oestrogen and progestogen. Increased risk of blood clots, particularly in smokers, women over 35, or those with a history of clotting disorders.

About

• Contains synthetic forms of oestrogen (usually ethinylestradiol) and progestogen.
• Highly effective when taken consistently and correctly, with a typical use failure rate of about 7% and a perfect use failure rate of less than 1%.

Action

• Inhibits Ovulation by inhibiting FSH release, follicular ripening and the LH surge
• Alters the cervical mucus
• Alters the endometrium

Benefits

• Effective Contraceptive
• Reduces dysmenorrhoea
• Reduces menorrhagia
• Reduced premenstrual syndrome
• Helps to regularise periods, reduce menstrual cramps, and decreases heavy menstrual bleeding.
• There is a reduced incidence of Ovarian and Endometrial cancer when taking the COCP
• Useful in polycystic ovary syndrome (PCOS), premenstrual syndrome (PMS), and endometriosis.

Risks

• Main risks are increased risk of thromboembolism
• Cardiovascular risk is increased by smoking, obesity, age, diabetes and hypertension and dyslipidaemias
• Weight gain, Reduced libido, Breast discomfort
• Mood changes, Breakthrough bleeding
• Cervical intraepithelial neoplasia, Breast Cancer

Contraindications

• Acute porphyrias
• Atrial fibrillation
• Benign hepatocellular adenoma
• Budd-Chiari syndrome
• Cardiomyopathy with impaired cardiac function
• complicated congenital heart disease
• Complicated valvular heart disease
• current breast cancer
• Hepatocellular carcinoma
• hypertension (blood pressure systolic 160mmHg or diastolic 100 mmHg or higher)
• hypertensive retinopathy
• ischaemic heart disease
• known thrombogenic mutations (e.g. factor V Leiden, prothrombin mutation, protein S, protein C and antithrombin deficiencies)
• less than 3 weeks postpartum in non-breastfeeding women with other risk factors for venous thromboembolism
• less than 6 weeks postpartum in breastfeeding women
• major surgery with prolonged immobilisation
• migraine with aura
• peripheral vascular disease with intermittent claudication
• positive antiphospholipid antibodies; previous or current venous thrombosis
• smoking in patients aged 35 years and over (15 or more cigarettes daily)
• Stroke
• Systemic lupus erythematosus with antiphospholipid antibodies
• Transient ischaemic attack

Advice

• Assessment: Blood pressure measurement. Detailed medical and family history to assess for contraindications Discussion of risks and benefits, including potential side effects. Assessment of side effects and adherence to the pill
• Missed Pills: If one pill is missed, it should be taken as soon as remembered, and the next pill taken at the usual time. If two or more pills are missed, additional contraceptive measures (e.g., condoms) should be used for the next 7 days.
• Drug Interactions: Certain medications, such as antibiotics, anticonvulsants, and St. John’s Wort, can reduce the effectiveness of COCPs. Women taking these medications should consider using an additional form of contraception.

Causes of Failed contraception

• Diarrhoea and small bowel disease
• Failed compliance
• Liver enzyme induction
• Broad spectrum antibiotics

References

• COMBINED HORMONAL CONTRACEPTIVES at BNF