Contraception and Special Groups

This article discusses contraception issues for four groups of women, those aged under 16 years, those taking liver-enzyme inducing drugs, women who are obese and those women with learning disabilities. There are separate articles on Contraception and the Mature Woman and Contraception and Young People.

• If a young person is assessed competent to consent to treatment by her ability to understand information provided, to weigh up the risks and benefits, and to express her own wishes, then this should be clearly documented in the medical records. Contraceptive advice or treatment can be provided to a competent young person (aged under 16 years) without parental consent or knowledge using the Fraser criteria:¹
  • The young person understands the advice.
  • The young person cannot be persuaded to inform her parents or to allow the clinician to inform them.
  • It is likely that the young person will continue to have sexual intercourse with or without the use of contraception.
  • The young person's physical or mental health may suffer as a result of withholding contraceptive advice or treatment.
  • It is in the best interests of the young person for the clinician to provide contraceptive advice, treatment or both without parental consent.
• Age alone does not limit contraceptive choices for young people. However the CSM recommend that, because of the reduction in bone mineral density, medroxyprogesterone acetate (Depo-Provera) be used only when other methods of contraception are inappropriate.
• Young women should be advised against the use of regular hormonal contraception before menarche, but if they are sexually active then condoms should be advocated.
• Sexual health: young people should be advised that the correct use of condoms is effective in the prevention of HIV infection. The evidence for a protective effect of against sexually transmitted diseases other than HIV is limited, but young people should be advised on the consistent and correct use of condoms in the promotion of safer sex.

• Contraception is not necessary in the 21 days after childbirth.
• Methods that are suitable choices for breastfeeding women include barrier methods, intra-uterine devices, the progestogen-only pill, injectable contraceptives, implants and sterilization. The combined oral contraceptive pill is not recommended, as it interferes with lactation.
• Methods that are suitable choices for women who are not breastfeeding after childbirth include COCs, barrier methods, IUDs, the POP, injectable contraceptives, the etonogestrel implant, and sterilization.
• Lactational amenorrhoea can be a very effective method of contraception if a woman is fully or almost fully breastfeeding, the baby is less than 6 months old, and menstruation has not yet returned.³

When to start contraception after childbirth

• A COC can be started 21 days after childbirth. If started later than this, additional contraception should be used for the first 7 days.
• A POP can be started 21 days after delivery (this is the UK advice but the World Health Organization recommends waiting until 6 weeks post-partum and using alternative methods of contraception from day 21 until the POP is started).
• Injectable contraceptives should be deferred until 6 weeks after childbirth but can be administered during the first 5 days after delivery in women who are not breastfeeding, as long as the woman accepts the risk of heavy and prolonged bleeding.
• The etonogestrel implant can be inserted 21 days after childbirth. If inserted later, additional contraceptive precautions should be used for the first 7 days.
• IUDs can be inserted:
• After vaginal delivery: usually inserted 4 weeks after childbirth.
• After Caesarian section: defer insertion for at least 6 weeks after a Caesarian section.
• If menstruation has returned, then IUDs are usually inserted at the end of a period and within 5 days after the calculated time of ovulation. They can be fitted at any time if there is no risk of conception since the last period.
• The diaphragm or cap can be used 6 weeks after delivery, and should always be checked for size and fit.

• Drugs which induce liver enzymes can reduce the efficacy of combined hormonal contraception, progestogen only pills and implants but do not appear to reduce the efficacy of progestogen-only injectables or the mirena coil.⁴
• Drugs which induce liver enzymes include:
  • Antifungals: griseofulvin
  • Antibiotics: rifampicin and rifabutin
  • Anti-epileptics: carbamazepine, phenytoin, phenobarbital, oxcarbazepine, topiramate
  • CNS stimulant: modafinil
  • Antiretroviral drugs: nelfinavir, nevirapine, ritonavir
  • St John's Wort
• Combined oral contraception:
  • Short-term course of an enzyme-inducing drug:
    • Additional contraceptive precautions should be taken whilst taking the enzyme-inducing drug and for at least 7 days after stopping it; if these 7 days run beyond the end of a packet the new packet should be started immediately without a break.
    • Rifampicin and rifabutin are such potent enzyme-inducing drugs that even if a course lasts for less than 7 days the additional contraceptive precautions should be continued for at least 4 weeks after stopping.
  • Long-term course of an enzyme-inducing drug:
    • Take a combination of oral contraceptives to provide a daily intake of ethinylestradiol 50 micrograms or more.
    • Tricycling (taking 3 or 4 packets without a break followed by a short tablet-free interval of 4 days) is recommended.
    • Rifampicin and rifabutin are such potent enzyme-inducing drugs that an alternative method of contraception is always recommended.
    • Appropriate contraceptive measures are required for 4 to 8 weeks after stopping the enzyme-inducing drug.
  • Contraceptive patches:
    • Additional contraceptive precautions are required whilst taking the enzyme-inducing drug and for 4 weeks after stopping.
    • If concomitant administration runs beyond the 3 weeks of patch treatment, a new treatment cycle should be started immediately without a patch-free break.
    • For women taking long term enzyme-inducing drugs another method of contraception should be considered.
• Progestogen-only pills
  • Advise alternative contraceptive methods.
• Progestogen-only implants
  • May continue with progestogen-only implants with additional contraceptive protection, such as condoms, when taking liver enzyme-inducers and for 4 weeks after they are stopped.
• Progestogen-only emergency contraception
  • Take a total dose of 2.25 mg levonorgestrel as a single dose as soon as possible and within 72 hours of unprotected sex.
  • Consider the use of a copper IUD, which is unaffected.

• For women with learning disabilities there is high use of injectable contraceptives and intrauterine contraceptive devices. However management of contraceptive needs of young women with an intellectual disability is similar in most cases to the management of non-disabled women.⁵
• However a person with learning disability or mental impairment may still be competent to make an informed choice regarding method of contraception and be able to use any method reliably.⁶
• It is therefore essential to consider the individual circumstances and wishes of women with learning disabilities and not necessarily opt for those methods that do not require the understanding and involvement of the user.

• Women with a BMI greater than 30 should be counselled regarding an increased risk of venous thromboembolism, and consider contraceptive methods other than the COC. Women with a BMI of more than 39 should not use a COC.
• The absolute risk of pregnancy using both combined oral contraceptives and progesterone only pills has been shown to increase in women having a BMI greater than 27.3 suggesting a possible reduction in efficacy of hormonal contraception.⁷ However other studies have not found any influence of body weight on the risk of accidental pregnancy with either form of oral contraceptive.⁸
• Diaphragms and caps should be checked if the woman gains or loses 3 kg or more in weight.