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Progestogen-Only Contraceptive (Oral) Pregnancy: Contraindicated in confirmed pregnancy. If taken inadvertently in early pregnancy — no evidence of teratogenicity.

Progestogen-Only Pill (POP / Mini-pill)

Brand names: Noriday (norethisterone), Micronor, Cerazette (desogestrel), Cerelle, Norgeston (levonorgestrel)

Adult dose

Dose: Desogestrel-based (Cerazette/Cerelle): 75 micrograms OD continuously. Traditional POP (norethisterone/levonorgestrel): 1 tablet OD continuously.
Route: Oral
Frequency: Once daily — no pill-free interval (taken continuously every day)
Max: 1 tablet OD
Desogestrel POP (Cerazette/Cerelle) has a 12-hour missed-pill window and is preferred — suppresses ovulation in ~97% of cycles. Traditional POP (norethisterone, levonorgestrel): only 3-hour missed pill window and primarily works by thickening cervical mucus (less reliable ovulation suppression). Start on day 1 for immediate protection; if day 2–5, use condoms for 2 days.

Paediatric dose

Route: Oral
Frequency: Once daily
Max: 1 tablet OD
Can be used from menarche. Suitable for adolescents with contraindications to oestrogen (migraine with aura, thrombophilia). Seek specialist advice for complex cases.

Dose adjustments

Renal

No dose adjustment required. Generally safe in renal impairment — no significant effect on fluid balance.

Hepatic

Contraindicated in active severe liver disease or hepatic tumours — same precaution as COCP.

Clinical pearls

  • Safe to use in women with migraine with aura — no oestrogen, no stroke risk elevation (UKMEC 2 at most)
  • Safe postpartum immediately — can start from day 1 postpartum; no waiting period regardless of breastfeeding status
  • Irregular bleeding is the most common reason for discontinuation — counsel women that irregular spotting is common, especially in first 3 months, before prescribing
  • Contraindications are fewer than COCP — suitable for older women, smokers, hypertensives, and those with cardiovascular risk factors

Contraindications

  • Current breast cancer (UKMEC 4)
  • Active severe liver disease
  • Unexplained vaginal bleeding (investigate first)
  • Hypersensitivity to progestogen

Side effects

  • Irregular bleeding/spotting (very common — counsel at initiation)
  • Amenorrhoea (particularly desogestrel)
  • Breast tenderness
  • Headache
  • Mood changes
  • Acne
  • Ovarian cysts (functional — usually resolve spontaneously)
  • Weight gain (modest)

Interactions

  • Enzyme-inducing drugs (rifampicin, carbamazepine, phenytoin) — significantly reduce efficacy; use copper IUD or DMPA instead
  • Ulipristal acetate (Ella One) — reduces POP efficacy for 9 days after emergency contraception; use barrier method

Monitoring

  • Blood pressure (baseline — though less critical than COCP)
  • Review bleeding pattern at 3 months
  • Annual review of ongoing suitability

Reference: BNFc; BNF 90; FSRH Progestogen-Only Pills Guideline 2022; 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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