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Combined Hormonal Contraceptive (Oestrogen + Progestogen) Pregnancy: Contraindicated in confirmed pregnancy. Stop immediately if pregnancy confirmed.

Combined Oral Contraceptive Pill (COCP)

Brand names: Microgynon 30, Rigevidon, Cilest, Yasmin, Marvelon, Gedarel

Adult dose

Dose: Standard: 1 tablet OD for 21 days, then 7-day pill-free interval (traditional 21/7 regimen). Extended/continuous cycling: 1 tablet OD continuously (84 active + 7 inactive, or fully continuous — reduces pill-free interval bleeding).
Route: Oral
Frequency: Once daily at the same time each day
Max: 1 tablet OD — dose varies by preparation (e.g. Microgynon: ethinylestradiol 30 micrograms + levonorgestrel 150 micrograms)
Start on day 1 of menstrual cycle for immediate protection. If started on days 2–5, use condoms for 7 days. Missed pill rules: if <24h late — take immediately, continue, no additional contraception needed. If >24h late — take missed pill, use condoms for 7 days; if missed in week 1 and unprotected sex, consider emergency contraception. Efficacy >99% with perfect use.

Paediatric dose

Route: Oral
Frequency: Once daily
Max: 1 tablet OD
Can be prescribed from menarche — no age-related dose change. Seek specialist advice for adolescents with comorbidities (migraines, thrombophilia, liver disease).

Dose adjustments

Renal

Use with caution in severe renal disease — fluid retention, hypertension risk. Not contraindicated per BNF but assess risk individually.

Hepatic

Contraindicated in active liver disease, hepatic tumours, or history of cholestatic jaundice of pregnancy — avoid until liver function returns to normal.

Clinical pearls

  • UKMEC categories: 1 = no restriction; 2 = benefits outweigh risks; 3 = risks generally outweigh benefits; 4 = absolute contraindication. Migraine with aura is UKMEC 4.
  • VTE risk: drospirenone and gestodene-containing pills (Yasmin, Marvelon) carry slightly higher VTE risk than levonorgestrel-containing pills — prescribe levonorgestrel-based pill first-line unless reason to choose otherwise
  • Enzyme inducers: women on long-term enzyme-inducing drugs should use copper IUD or DMPA — COCPs unreliable regardless of dose
  • Breast cancer: COCP associated with small increase in breast cancer risk (RR ~1.24) — returns to baseline after 10 years of stopping

Contraindications

  • Migraine with aura (UKMEC 4 — absolute contraindication — VTE/stroke risk)
  • Personal history of VTE or thrombophilia
  • Ischaemic heart disease or stroke history
  • Uncontrolled hypertension (>160/100)
  • Smoking ≥15 cigarettes/day AND age ≥35 (UKMEC 4)
  • Breastfeeding <6 weeks postpartum
  • Active liver disease or hepatic tumours
  • Oestrogen-dependent malignancy (breast cancer)
  • Prolonged immobility

Side effects

  • VTE (increased 3–4× vs. non-users — absolute risk still low: ~6/10,000 women/year)
  • Arterial thrombosis (stroke, MI — mainly in smokers and hypertensives)
  • Nausea, breast tenderness
  • Headache
  • Mood changes
  • Breakthrough bleeding
  • Hypertension
  • Reduced libido
  • Cervical ectropion

Interactions

  • Enzyme-inducing drugs (rifampicin, carbamazepine, phenytoin, St John's Wort) — significantly reduce contraceptive efficacy; use barrier or LARC alternative
  • Lamotrigine — COCP reduces lamotrigine levels; dose adjustment may be needed (risk of seizures)
  • Broad-spectrum antibiotics — historical concern; current guidance (FSRH 2017): antibiotics do NOT reduce COCP efficacy (unless enzyme-inducing)

Monitoring

  • Blood pressure (before starting and at 6 months, then annually)
  • BMI
  • Review risk factors annually (smoking, migraines, family history of VTE)
  • No routine blood tests required

Reference: BNFc; BNF 90; FSRH Guidelines on Combined Hormonal Contraception 2019 (updated 2023); UKMEC 2016. Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

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