Contraception Flashcards
(157 cards)
What should be discussed with patients when counselling them on contraception?
Different options
Suitability (including assessing contraindications and risks)
Effectiveness
Mechanism of action
Instruction on use
Key methods of contraception
Natural family planning (“rhythm method”)
Barrier methods (i.e. condoms, diagpnram with spermicides )
Combined contraceptive pills
Progestogen-only pills
Coils (i.e. copper coil or Mirena)
Progestogen injection
Progestogen implant
Surgery (i.e. sterilisation or vasectomy)
The Faculty of Sexual & Reproductive Healthcare (FSRH) has UK Medical Eligibility (UKMEC) guidelines published in 2016 (updated in 2019) to categorise the risks of starting different methods of contraception in different individuals - what are the implications of the various different levels?
UKMEC 1: No restriction in use (minimal risk)
UKMEC 2: Benefits generally outweigh the risks
UKMEC 3: Risks generally outweigh the benefits
UKMEC 4: Unacceptable risk (typically this means the method is contraindicated
Explaining contraceptive method effectiveness
What 99% effective means is that if an average person used this method of contraception correctly with a regular partner for a single year, they would only have a 1% chance of pregnancy.
It is essential to distinguish between the effectiveness of perfect use and typical use. This is especially important with methods such as natural family planning, barrier contraception and the pill, where the effectiveness is very user-dependent. Long-acting methods such as the implant, coil and surgery are the most effective with typical use, as they are not dependent on the user to take regular action.
Common contraceptive contraindications?
Breast cancer, VTE: avoid any hormonal contraception and go for the copper coil or barrier methods
Cervical or endometrial cancer: avoid the intrauterine system (i.e. Mirena coil)
Wilson’s disease: avoid the copper coil
Latex allergy: Avoid latex products
What are the specific risk factors that should make you avoid the combined contraceptive pill (UKMEC 4)?
Uncontrolled hypertension (particularly ≥160 / ≥100)
Migraine with aura
History of VTE
Aged over 35 smoking more than 15 cigarettes per day
Major surgery with prolonged immobility
Vascular disease or stroke
Ischaemic heart disease, cardiomyopathy or atrial fibrillation
Liver cirrhosis and liver tumours
Systemic lupus erythematosus and antiphospholipid syndrome
Contraception considerations in older and perimenopausal women
After the last period, contraception is required for 2 years in women under 50 and 1 year in women over 50
Hormone replacement therapy does not prevent pregnancy, and added contraception is required
The combined contraceptive pill can be used up to age 50 years, and can treat perimenopausal symptoms
The progestogen injection (i.e. Depo-Provera) should be stopped before 50 years due to the risk of osteoporosis
Women that are amenorrhoeic (no periods) when taking progestogen-only contraception should continue until when (to prevent pregnancy)?
FSH blood test results are above 30 IU/L on two tests taken six weeks apart (continue contraception for 1 more year)
55 years of age
Considering contraception for women under 20
Combined and progestogen-only pills are unaffected by younger age
The progestogen-only implant is a good choice of long-acting reversible contraception (UK MEC 1)
The progestogen-only injection is UK MEC 2 due to concerns about reduced bone mineral density
Coils are UKMEC 2, as they may have a higher rate of expulsion
For how long are women considered unlikely to become pregnant following child birth
21 says
Lactational amenorrhea is over 98% effective as contraception under what circumstances and for how long
6 months
Fully breastfeeding and amenorrheic
What methods of hormonal contraception are safe when breastfeeding
The progestogen-only pill and implant are considered safe in breastfeeding and can be started at any time after birth.
When should the COCP be avoided post partum
During breastfeeding
Up to 6 weeks postpartum UKMEC 4
After to 6 weeks postpartum UKMEC 2
When can an IUD or IUS be inserted postpartum?
A copper coil or intrauterine system (e.g. Mirena) can be inserted either within 48 hours of birth or more than 4 weeks after birth (UKMEC 1), but not inserted between 48 hours and 4 weeks of birth (UKMEC 3).
Barrier contraception
Condoms
(Condoms are about 98% effective with perfect use, but can be significantly less effective with typical use (82%). Standard condoms are made of latex. Using oil-based lubricants can damage latex condoms and make it more likely they will tear. Polyurethane condoms can be used in latex allergy)
Diaphragms and Cervical Caps
(Diaphragms and cervical caps are silicone cups that fit over the cervix and prevent semen from entering the uterus. The woman fits them before having sex, and leaves them in place for at least 6 hours after sex. They should be used with spermicide gel the further reduce the risk of pregnancy.
When used perfectly with spermicide, diaphragms and cervical caps are around 95% effective at preventing pregnancy. They offer little protection against STIs, and condoms need to be used for STI protection.)
Dental Dams
(Dental dams are used during oral sex to provide a barrier between the mouth and the vulva, vagina or anus. They are used to prevent infections that can be spread through oral sex, including:
Chlamydia
Gonorrhoea
Herpes simplex 1 and 2
HPV (human papillomavirus)
E. coli
Pubic lice
Syphilis
HIV)
COCP mechanism of action
The COCP prevents pregnancy in three ways:
Preventing ovulation (this is the primary mechanism of action) (inhibits GnRH, LH and FSH release)
Progesterone thickens the cervical mucus
Progesterone inhibits proliferation of the endometrium, reducing the chance of successful implantation
Why does a withdrawal bleed occur during the 7 day break on the COCP
The lining of the endometrium is maintained in a stable state while taking the combined pill. When the pill is stopped the lining of the uterus breaks down and sheds. This leads to a “withdrawal bleed“. This is not classed as a menstrual period as it is not part of the natural menstrual cycle. “Breakthrough bleeding” can occur with extended use without a pill-free period.
Monophasic vs multiphasic COCP
Monophasic pills contain the same amount of hormone in each pill
Multiphasic pills contain varying amounts of hormone to match the normal cyclical hormonal changes more closely
COCP - monophasic formulations
ethinylestradiol and levonorgestrel (Microgynon)
ethinylestradiol and norethisterone (Loestrin)
ethinylestradiol and norgestimate (Cilest)
ethinylestradiol and drospirenone (Yasmin)
ethinylestradiol and desogestrel (Marvelon)
What formulation of COCP is recommended as first line and why?
The NICE Clinical Knowledge Summaries (2020) recommend using a pill with levonorgestrel or norethisterone first line (e.g. Microgynon or Leostrin). These choices have a lower risk of venous thromboembolism.
Which formulations of COCP are reccomended for premenstural syndrome and why?
Yasmin and other COCPs containing drospirenone are considered first-line for premenstrual syndrome.
Drospirenone has anti-mineralocorticoid and anti-androgen activity, and may help with symptoms of bloating, water retention and mood changes.
Continuous use of the pill, as opposed to cyclical use, may be more effective for premenstrual syndrome.
What formulation of COCP is most useful in treating acne and how should it be taken
Dianette and other COCPs containing cyproterone acetate (i.e. co-cyprindiol) can be considered in the treatment of acne and hirsutism.
Cyproterone acetate has anti-androgen effects, helping to improve acne and hirsutism.
The oestrogenic effects mean that co-cyprindiol has a 1.5 – 2 times greater risk of venous thromboembolism compared to the first-line combined pills (e.g. Microgynon).
It is usually stopped three months after acne is controlled, due to the higher risk of VTE.
What are three common regimes used to take the COCP?
Standard use: 21 days on and 7 days off
63 days on (three packs) and 7 days off (“tricycling“)
Continuous use without a pill-free period standard
COCP - Side effects and risks
Unscheduled bleeding is common in the first three months and should then settle with time
Breast pain and tenderness
Mood changes and depression
Headaches
Hypertension
Venous thromboembolism (the risk is much lower for the pill than pregnancy)
Small increased risk of breast and cervical cancer, returning to normal ten years after stopping
Small increased risk of myocardial infarction and stroke