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A - BNF - CHAPTER 7 GENITO-URINARY SYSTEM > Contraception > Flashcards

Flashcards in Contraception Deck (38)
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1
Q

Combined hormonal contraceptives

A

Oral contraceptives containing an oestrogen and a progestogen (COC) are effective preparations for general use. They inhibit ovulation.

2
Q

Advantages of COC include:

A
  • Reliable and reversible - Reduced incidence of premenstrual tension
  • Reduced dysmenorrhoea and menorrhagia
  • Reduced risk of pelvic inflammatory disease
  • Reduced risk of ovarian + endometrial cancer
  • Less benign breast disease
3
Q

Do not use COC in

A

women >50y

4
Q

COC - define monophasic/phasic

A

• COC containing a fixed amount of an oestrogen and progestogen in each active tablet are termed monophasic, those with varying amounts of the two hormones are termed phasic.

5
Q

Choice

A
  • The majority of combined oral contraceptives contain ethinylestradiol as the oestrogen component. The ethinylestradiol content of combined oral contraceptives varies from 20-40 mcg.
  • Generally, a preparation with the lowest oestrogen + progestogen content which gives good cycle control with minimal side effects is chosen.
  • Low strength preparations (containing 20mcg of ethinylestradiol) are appropriate for women with risk factors for circulatory disease
  • Standard strength preparations (containing 30-40mcg of ethinylestradiol) are appropriate for standard use.
6
Q

Reason to stop immediately

A

• Sudden, severe chest pain (even if not radiating to left arm)
• Sudden breathlessness (or cough with blood-stained sputum)
• Unexplained swelling or severe pain in calf of one leg
• Severe stomach pain
• Serious neurological side effects (unusual severe headache, affected vision, affected hearing, etc.)
• Hepatitis, jaundice, liver enlargement
• Raised blood pressure (systolic >160mmHg or diastolic >95mmHg)
• Prolonged immobility after surgery or leg injury
- Detection of a risk factor which contraindicates oestrogen treatment (smoking >40 ciggarettes, personal history of arterial or VTE, migraine with aura, DM with complications, BMI >35, >50y, TIA w/o headache)

7
Q

Oestrogen and surgery

A

Oestrogen should be discontinued 4 weeks before major elective surgery. Recommence at first menses occurring at least 2 weeks after full mobilisation

8
Q

Monophasic 21-day preparations examples

A

Levest, Microgynon and Rigevidon

9
Q

Monophasic 28-day preparations examples

A

Microgynon 30 ED

10
Q

Phasic 21-day preparations examples

A

Logynon

11
Q

Phasic 28-day preparations examples

A

Logynon ED

12
Q

BNF warnings

• COCs

A

• COCs increase the risk of VTE especially during the first year of treatment and following any breaks of 4 weeks or more in therapy… the risk is increased by being overweight, smoking and age >35

13
Q

Risk factors for arterial disease (use with caution if 1 factor present, but avoid if 2 or more present):

A
  • Family history of arterial disease in first degree relative under 45
  • Diabetes
  • Hypertension (systolic >140mmHg, diastolic >90mmHg)
  • Age over 35
  • Obesity
  • Migraine without aura
  • Smoking (avoid if smoking >40 cigarettes daily)
14
Q

There is a small increase in the risk of developing

A

• breast cancer and cervical cancer. The risk diminishes after stopping and disappears by about 10 years.

15
Q

Missed pills

A

(A missed pill is one that is >24 hours late (COC) or >3hours late (POP))
• If a woman forgets to take a pill, it should be taken as soon as she remembers and the next one taken at the normal time (even if this means taking 2 pills together)
• If a woman misses 2 or more pills (especially from the first 7 in the packet) she may not be protected. She should take an active pill as soon as she remembers and then resume normal pill- taking. In addition, she must either abstain from sex or use an additional method of contraception such as a condom for the next 7 days. If these 7 days run beyond the end of the packet, the next packet should be started at once, omitting the pill free interval (or in the case of everyday pills, omitting the 7 inactive tablets)
• If a woman vomits within 2 hours of taking a pill, she should take another pill. In cases of persistent vomiting or severe diarrhoea lasting more than 24 hours, additional precautions should be taken. If the vomiting/diarrhoea occurs during the last 7 tablets, the next pill-free interval should be omitted.

16
Q

The effectiveness of COCs can be reduced if taken with

A
  • The effectiveness of COCs can be reduced if taken with enzyme inducers (i.e. carbamazepine, phenytoin, phenobarbital, ritonavir, St John’s wort and rifampicin.). In this case patients should take progestogen only contraceptives or intra-auterine devices.
  • No additional contraceptive measures are needed if COCs are taken with antibiotics unless, vomiting and diarrhoea occur, or the antibiotic is an enzyme inducer.
17
Q

Progestogen-only contraceptives

A
  • Progestogen-only pills may be more suitable for patients with a history of VTE, they do not interact with enzyme inducers.
  • They do however, require more strict dosing times and do not provide protection if missed by just 3 hours.
18
Q

Intra-auterine devices

A
  • The intra-auterine device (IUD) is a suitable contraceptive for women of all ages, however it is less appropriate for those with an increased risk of pelvic inflammatory disease e.g. women under 25 years.
  • Smaller devices have been introduced to minimise side effects
  • Fertility declines with age and therefore a copper IUD which is fitted in a woman over the age of 40 may remain in the uterus until menopause.
19
Q

Emergency contraception - most effective

A

Insertion of a copper IUD is the most effective form of emergency contraception and should be offered to all women who have had UPSI but do not want to conceive. It can be inserted up to 5 days after UPSI. It is not affected by BMI, body-weight or by other drugs.

20
Q

Emergency hormonal contraception includes

A

Levonorgestrel and Ulipristal – they should be taken as soon as possible following unprotected sexual intercourse (UPSI) for increased efficacy.

21
Q

Emergency contraception

A
  • Levonorgestrel (Levonelle) is effective for up to 72 hours after sex but can be used unlicensed for up to 96 hours. Ulipristal (ellaOne) is effective for up to 120 hours. They are equally effective.
  • It is possible that a higher bodyweight or BMI could reduce the effectiveness of oral emergency contraception, particularly Levonorgestrel – if BMI is greater than 26kg/m2 or bodyweight greater than 70kg, it is recommended that either ulipristal or a double dose of levonorgestrel (unlicensed) is given.
  • Vomiting: same as above
  • Levonelle should not be taken if the woman’s period is overdue, if they have severe hepatic dysfunction or acute porphyria.
  • If the patient is currently taking regular hormonal contraception… they should continue as normal.
  • EHC drugs interact with enzyme-inducing drugs and may not work. A double dose (3mg) of Levonelle can be given (unlicensed) if necessary – but this may increase the chances of nausea and unusual bleeding
  • Situations involving children under the age of 13 should be classified as ABUSE and referred to social services. Children under 16 should be treated as adults (Use fraser guidelines).
  • EHC can be supplied to patient representative if satisfied it is a genuine request - speak to patient over the phone if representative cannot answer all questions.
  • Emergency hormonal contraception methods do not provide ongoing contraception. After taking levonorgestrel, women should start suitable hormonal contraception immediately. However, women should wait 5 days after taking ulipristal acetate before starting hormonal
22
Q

After taking EHC, the woman may experience

A

• unusual bleeding, headaches and nausea, and their next period may be early or late. They should use condoms until their next period and seek medical attention if lower abdominal pain is present (could be ectopic pregnancy), of if their next period is abnormally light, heavy or missing.

23
Q

Levonelle 1500 is a POM, but the pharmaceutically identical Levonelle OneStep

A

•can be sold to women >16. It can be supplied OTC in advance of UPSI… as long as woman is competent, and use is appropriate

24
Q

ulipristal and breastfeeding

A

If ulipristal taken as emergency contraception. Avoid breastfeeding for one week after taking it

25
Q

Contraceptives interactions

A

The effectiveness of combined oral contraceptives, progestogen-only oral contraceptives, contraceptive patches, vaginal rings, and emergency hormonal contraception can be considerably reduced by interaction with drugs that induce hepatic enzyme activity (e.g. carbamazepine, eslicarbazepine acetate, nevirapine, oxcarbazepine, phenytoin, phenobarbital, primidone, ritonavir, St John’s Wort, topiramate and, above all, rifabutin and rifampicin) and possibly also griseofulvin.

26
Q

Contraceptives interactions - Women on COCs should be advised to change to a

A

Women on COCs should be advised to change to a reliable contraceptive method that is unaffected by enzyme- inducers, such as some parenteral progestogen-only contraceptives (medroxyprogesterone acetate and norethisterone) or intra-uterine devices (levonorgestrel). This should be continued for the duration of treatment and for four weeks after stopping.

27
Q

Contraceptives interactions - Short course (<2 months) of an enzyme-inducing drug

A

Continuing the combined hormonal contraceptive method may be appropriate if used in combination with consistent and careful use of condoms for the duration of treatment and for four weeks after stopping the enzyme-inducing drug.

28
Q

Contraceptives interactions - Long-term course (>2 months) of an enzyme-inducing drug (except rifampicin/rifabutin) or griseofulvin:

A

Use a monophasic COC at a dose of ethinylestradiol 50mcg or more daily [unlicensed use] and use either an extended or a ‘tricycling’ regimen (i.e. taking three packets of monophasic tablets without a break followed by a shortened tablet-free interval of four days [unlicensed use]); continue for the duration of treatment with the interacting drug and for four weeks after stopping.
Use of contraceptive patches and vaginal rings (including concurrent use of two patches or two vaginal rings) is not recommended for women taking enzyme-inducing drugs over a long period.

29
Q

Contraceptives interactions - Long-term course (>2 months) of rifampicin or rifabutin:

A

An alternative method of contraception (such as an IUD) is always recommended because they are such potent enzyme-inducing drugs; the alternative method of contraception should be continued for four weeks after stopping the enzyme-inducing drug.

30
Q

Contraceptives interactions - Hormonal emergency contraception interactions:

A

Levonorgestrel should not be used (as emergency hormonal contraception) within 5 days of administration of ulipristal acetate (as emergency hormonal contraception), as the contraceptive effect of ulipristal acetate may be reduced by progestogens.
Ulipristal acetate is not recommend for use in women who have severe asthma treated by oral corticosteroids, due to the antiglucocorticoid effect of ulipristal acetate.

31
Q

Oestrogens - increased risk of

A

• Increased risk of VTE. Certain risk factors further increase risk of VTE:
o Type of progestogen: Desogestrel, Gestodene, Drosperinone
o Obesity BMI >30 - Age >35y
o Smoking - Superficial thrombophlebitis
o Primary relative <45y with VTE - Long term immobilisation
• Increased risk of arterial thromboembolism. Certain risk factors further increase risk of ATE:
o Diabetes Mellitus, HTN, Migraine without aura

                                                                                        AVOID IF 2 OR MORE RISK FACTORS PRESENT
32
Q

travel + using COC

A

journeys longer than 3h : reduce risk by wearing compression stocking + leg exercises

33
Q

benefits of COC

A
  • reduces risk of ovarian and endometrial cancer
  • reduces dysmenorrhea and menorrhagia, premenstrual tension, reduced risk of PID, less benign breast cancer, less symptomatic fibroids or functional ovarian cysts
34
Q

POP missed pill

A

> 3h (desogestrel >12h)

  • Take ASAP + use condom for 2 days
  • Take EHC if unprotected sex occurs before 2 pills are taken correctly
35
Q

Missed patch

A

EVRA

  • 1 cycle weekly patch for 3 weeks then 1 week patch free
  • Detached for >24h or delayed application of start of cycle - apply new patch ASAP, start a new 1 cycle + condom for 7 days
  • Delayed application in middle of cycle (start of week 2 day 8 or week 3 day 15) - <48h apply a new patch and continue as normal. >48h start a new day 1 cycle + condom for 7 days
36
Q

IUD side effects

A
  • pain on insertion and bleeding
  • Uterine perforation
  • risk of infection
37
Q

Parenteral contraceptives

A
  • Medroxyprogesterone injection - 2years
  • Norethisterone injection - 8 weeks
  • Etonogestrel implant - 3 years
38
Q

Nexplanon (etonogestrel) MHRA

A

Reports of device in vasculature and lung

- Implants may reach the lung via pulmonary artery