Contraception – Progesterone Only Pill

Progesterone Only Pills contain:

  • Levonorgesterol (LNG) (traditional POP)
  • Norethisterone (NET) (Traditional POP)
  • Desogesterol (DSG) (=cerazette)
  • If used correctly they’re more than 99% effective
  • If on enzyme inducing drug then it won’t be effective:
    • if they’re on a short course (less than two months) they can continue on POP but be aware they need to take extra precautions for 28days after stopping
  • Desogesterol (DSG) (Cerazette)pills are a bit better than tradtional POPs as they offer a 12 hour window for missed pill and they stop ovulation in 97% of cycles
  • There is an increased risk of pregnancy for those with higher BMI


  • If she vomits within two hours of taking a pill she should take another one
  • If she misses that second one she should use additional precautions until 48hours after normal pill taking has resummed

Other benefits / risks

  • The POP may offer some benefits in the management of dysmenorrhoea
  • Theres limited evidence avaibale but none showing there’s any increased risk of cardiovascular disease with the POP.
  • There’s no evidence to show link with breast cancer but it is possible – any association is likely to be small and reduce after stopping taking the POP.

Mood changes

  • Theres some report of mood changes but no evidence to show it’s a causal effect


  • Overall risk of ectopic pregnancy reduced but if pregnancy does occur 1 in 10 may be ectopic
  • Fertility probably returns to normal as soon as it’s discontinued

Side Effects

  • Changes in bleeding pattern is common
    • There’s no evidence that changing the type and dose of POP will improve bleeding but it may help some women
  • No proof of altered libido but can’t be ruled out
  • No evidence supporting any change in weight association

Follow Up

  • you can give them a year’s supply
  • follow up is tailored to them
  • Can be used until age 55 when natural loss of fertility can be assumed
  • If they are over 50:
    • continue using POP
    • check FSH levels on two occasions 6 weeks apart
    • if both are over 30IU/l then ovarian failure can be assumed but
    • they must continue using POP or barrier for a further one year