Methods of contraception

  • Barrier - condoms
  • Combined hormonal contraception (CHC) - COCP, combined transdermal patch
  • Progestogen only - POP, implant, injectable
  • Long-acting reversible contraceptives (LARCs) 
    • Highly effective contraception, as not dependent on user compliance
    • LARCs include:
      • Intrauterine contraception
        • Levonorgestrel IUS (mirena) 
        • Copper IUD
      • Progestogen-only implant

 

NICE advises to offer whichever method of contraception is preferred by the woman, unless CId.

  

Adverse Effects 

  

Levonorgestrel IUS

  • 1/20 risk of expulsion
  • Hormonal side effects - acne, breast tenderness, mood changes
  • Pelvic pain, cramping
  • Irregular periods/Amenorrhoea - periods become irregular, or stop altogether  

 

Copper IUD

  • Expulsion 1/20 
  • Pelvic pain, cramping 
  • Bleeding - Menorrhagia, intermenstrual bleeding and dysmenorrhoea

  

Progestogen-only implant (e.g. Nexplanon subdermal implant)

  • Unscheduled bleeding, irregular, heavy
  • Reduced efficacy with enzyme inducers 

 

Contraindications 

 

A full list of UKMEC 4 (contraindicated) and UKMEC 3 (risks>benefits) can be viewed  at the following: https://www.fsrh.org/standards-and-guidance/documents/ukmec-2016/


Combined hormonal contraceptives - contraindications 

Some of the most common UKMEC 4 criteria for combined hormonal contraception include:

  • Postpartum
    • Breastfeeding and < 6 weeks postpartum
    • < 3 weeks postpartum with RFs for VTE
  • Past-medical history:
    • Uncontrolled HTN (> 160/100mmHg)
    • Vascular disease
    • History of ischaemic heart disease, AF, heart failure or stroke/TIA
    • History of VTE 
    • Major surgery with prolonged immobilisation 
    • Migraine with aura
  • Genetics:
    • Breast cancer, or carrier of BRCA1/2 or known thrombogenic mutation 
  • Smoking:
    • Age > 35 and smokes > 15/day

 

Intrauterine device - contraindications 

Both the Cu-IUD and LNG-IUS are contraindicated in the following:

  • Unexplained vaginal bleeding
  • Current pelvic inflammatory disease or STI (chlamydia/ gonorrhoea)
  • Postpartum sepsis 

 

Unexplained PV bleeding

  • UKMEC 4 - Cu-IUD, LNG-IUS
  • UKMEC 3 - progestogen only implant, progestogen-only injectable 


 

Teratogenic risk

Women (inc. their partners) who are taking teratogenic drugs (e.g. lithium or sodium valproate):

  • Highly effective contraception is recommended - such as LARC
  • If wishes to use COCP or POP - should use additional contraceptives (such as condoms) 

 
 

Liver enzyme inducers and drug interactions

Inducers

  • Inducers can interact with, and reduce the efficacy of hormonal contraception
  • Offer LARCs which are unaffected (CU-IUD, LNG-IUS, Depo injection)
  • Inducers include (PCBRAS)
    • Phenytoin
    • Carbamazepine
    • Barbiturates
    • Rifampicin
    • Alcohol (chronic xs) and Antiretrovirals (-avirs and NNRTIs)
    • Sulphonylureas, St John’s Wort 

Drug interactions 

  • Note - Lamotrigine is NOT an inducer BUT may interact with POP/CHC - avoid CHC (reduces lamotrigine efficacy - inc. seizure risk), POP inc. lamotrigine levels increasing adverse effects etc.


  


Oral contraceptives - Missed Pill Rules

 

Progestogen-Only pill

  • A missed pill is defined as any pill > 3 hours late (if missed by < 3hrs, take as normal)
    • Exceptions - desogestrel POP = 12 hours,  Drospirenone POP = 24 hours 
  • Advice: 
    • Take missed pill now 
    • Use additional precautions for the next 48 hours 
    • Emergency contraception is needed if they have had sex since missing the pill OR within 48 hours of restarting the regular pills 
  • Nb. Irregular periods are the most common side effect of POP

 

Combined oral contraceptive pill

  • Missed pill is defined as any pill which is > 24 hours late
  • Advice
    • 1 missed pill - take the missed pill now, as soon as it is remembered (even if 2 taken on the same day), and then continue as normal. No extra precautions needed.
    • 2 missed pills 
      • Take a pill now (as soon as remember), (even if 2 on the same day)
      • Extra precautions needed for 7 days
      • AND:
        • If missed pill from 1st 7 in packet - need emergency contraception
        • If missed pill from last 7 in packet - start the next packet without the pill-free week 
  • Vomiting and diarrhoea 
    • Vomit within 3 hours - take another pill
    • V&D for > 24hrs 
      • Follow missed pill rules (counting each day of V&D as 1 missed pill)
      • Avoid sex or use barrier during illness and 7 days after