Contraception

Combined oral contraceptive pill: overview 622 Combined oral contraceptive pill: regimes 624 Progestagen-only pill 626

Other forms of contraception 628 Emergency contraception 630

Female sterilization: preoperative considerations 632 Female sterilization: procedure 634

622 CHAPTER 20 Contraception

Combined oral contraceptive pill: overview

COCP provides reliable, effective contraception, with a failure rate of 0.2–0.3 per 100 woman-years. Modern COCPs all contain ethinylestradiol (20–35 micrograms) and are classified by type of progestagen they contain. The newer quadriphasic COCP Qlaira® is an exception; it contains estradiol valerate.

Type of progestagen in the COCP

•2nd generation:

•norethisterone

•levonorgestrel.

•3rd generation:

•desogestrel

•gestodene (less androgenic)

•norgestimate (metabolized to levonorgestrel).

•Yasmin®: contains drospirenone (antiandrogenic and weak antidiuretic properties).

•Co-cyprindiol:

•contains cyproterone acetate (antiandrogenic)

•useful in the treatment of hirsutism and acne.

Mode of action

•Ovulation inhibition (–ve feedback on hypothalamus + pituitary).

•Thickened cervical mucus preventing sperm penetration.

•Thin endometrium preventing implantation.

Side effects

•Breakthrough bleeding: may occur especially in the first 3mths. Missed pills, STIs, and pregnancy should all be considered.

•Headache: try dose of ethinylestradiol or change of progestagen.

•Weight gain: no evidence of additional weight gain due to COCP.

Contraindications to the COCP

•Pregnancy.

•Personal history of thromboembolic disease.

•Undiagnosed genital tract bleeding.

•Cardiovascular disorders.

•Migraine with aura.

•Oestrogen dependent tumours.

•Active hepatobiliary disease or liver tumours.

•Hypertension and diabetes.

•35yrs old who smoke (may use 1yr after cessation).

•BMI 35.

COMBINED ORAL CONTRACEPTIVE PILL: OVERVIEW 623

Advantages and disadvantages of the COCP

Advantages

•dMenstrual blood loss and pain.

•Menstrual cycle can be regulated and controlled.

•dRisks of benign ovarian tumours.

•dIncidence of PID.

•Improvement in skin condition in acne vulgaris.

•Possible dsymptoms:

•premenstrual syndrome

•endometriosis.

•dRisks of colorectal cancer.

•dOvarian cancer risk 50% during use and for >15yrs after.

Disadvantages

•iRisks (although absolute risk is very low)

•VTE

•stroke

•cardiovascular disease.

•Small irisk of breast cancer: returns to the background risk 10yrs after stopping.

•Very small association with irisk of cervical cancer.

The pill and VTE

The absolute risk of VTE is:

•Background risk: 5:100 000 women/yr.

•2nd generation COCP: 10–15:100 000 women/yr.

•3rd generation COCP: 25:100 000 women/yr.

•Pregnancy: 60:100 000 women/yr.

Current CSM advice regarding the COCP and VTE

As long as women are well informed of the small increased risk of thrombosis associated with 3rd generation pills, and do not have any medical contraindications, it should be a matter of user preference and clinical judgement on which COCP is to be prescribed. Combined hormonal contraception is contraindicated where there is a personal history of VTE or a known thrombogenic gene mutation.

COMBINED ORAL CONTRACEPTIVE PILL: REGIMES 625

Missed pill rules

If 1 pill is missed

•Take the missed pill as soon as possible.

•Continue the rest of the pack as usual.

•No additional contraception is required.

If 2 or more pills are missed

•Take the most recent missed pill as soon as possible.

•Continue the rest of the pack as normal.

•Additional contraceptive cover is required until 7 consecutive pills have been taken.

•If the missed pills are in day 1–7: emergency contraception should be considered.

•If the missed pills are in day 8–14: emergency contraception not needed.

•If the missed pills are in day 15–21: omit the pill free interval.

1Qlaira® has different missed pill rules (see manufacturer’s advice).

Other combined hormonal contraceptives

Vaginal ring

•Ethinylestradiol with etonogestrel.

•Remains in situ for 21 days, then removed for 7 days to induce a withdrawal bleed.

Transdermal patch

•Ethinylestradiol with norelgestromin.

•Replaced weekly for 21 days, then 7 patch-free days to induce a withdrawal bleed.

2Efficacy and side effect profile as for COCP.

626 CHAPTER 20 Contraception

Progestagen-only pill

POPs currently marketed contain either levonorgestrel, norethisterone, or etynodiol acetate. The failure rate ranges from 0.3 to 4.0% per 100 woman-years and decreases with age.

2 Cerazette®, a POP (75 micrograms desogestrel), reliably blocks ovulation, increasing efficacy.

1To be reliable, a POP must be taken at the same time every day.

Mode of action

•Thickened cervical mucus (4h after dose).

•Thin endometrium preventing implantation.

•Inhibition of ovulation (60% old POP, 97% desogestrel).

Indications

Useful in conditions where COCP is contraindicated:

•During lactation—has no effect on quality or quantity of milk.

•Sickle cell disease.

•SLE and other autoimmune diseases.

Side effects

•Menstrual disturbance—regular (40%), irregular (40%), or amenorrhoea (20%).

•Headaches, nausea, mood swings, abdominal bloating, and breast tenderness—usually subside after a few months.

Drug interactions

•Broad spectrum antibiotics do not affect the efficacy of POP.

•Rifampicin and other enzyme-inducing drugs increase the metabolism of POP, leading to a reduction in efficacy.

Contraindications to the POP

•Pregnancy.

•Undiagnosed genital tract bleeding.

•Severe arterial disease.

•Active hepatic disease.

•History of recurrent follicular cysts.

PROGESTAGEN-ONLY PILL 627

How to take the POP

•Take the pill daily, at the same hour.

•If started on day 1 of the cycle no extra contraception is required.

•If started after day 5, extra contraception should be used for 48h.

•After miscarriage or TOP: start on the day of the miscarriage or TOP.

•After delivery: start on day 21 (whether breast-feeding or not). From COCP to POP: if the first POP is taken the day after the last active COCP, no other contraception is needed.

Missed POP rules

•If >3h late or 27h since last dose:

•take missed pill as soon as possible

•take subsequent pill at the usual time

•use extra contraception for the next 48h.

•If vomit within 2h of ingestion:

•take another pill now

•use extra contraception for the next 48h.

1For Cerazette® same rules apply if missed pill is >12h late.

628 CHAPTER 20 Contraception

Other forms of contraception

Injectable progestagen

Depo-Provera® (MDPA) (given 12-weekly)

•Useful for women who are unable or unwilling to take a pill.

•Contains 150mg of medroxyprogesterone.

2Very effective (failure rate <1 per 100 woman-years).

Side effects

•Menstrual disturbance (regular, irregular, or even amenorrhoea).

•Delayed conception (fertility may not return for 6–12mths).

•Weight gain (probably due to progestagen iappetite).

•Bone loss (small risk of dbone density with prolonged use).

Progestagen-only subdermal implant

Nexplanon® (has replaced Implanon® in the UK):

•Contains etonogestrel.

•Insertion and removal involves a small procedure under local anaesthetic (inserted into the arm).

•It lasts for 3yrs.

•Is radio-opaque.

•Specially designed applicator to minimize incorrect insertion.

2Highly effective (failure rate reported as <0.1 per 100 woman-years).

Side effects

Menstrual disturbance—20% amenorrhoea, 50% erratic bleeding.

Copper-bearing IUCD

•Provides long-term reversible contraception.

•Insertion is usually easy.

•May be retained beyond the menopause.

2Very effective (failure rate of 0.6–0.8 per 100 woman-years).

Mode of action

•Foreign body reaction in the endometrium prevents implantation.

•Copper content may inhibit spermatozoa motility.

Complications

•Irregular PV bleeding, especially first 3–6mths.

•Risk of infection: screen for Chlamydia prior to insertion.

•IUCD expulsion: most common in the first 3mths after insertion.

•Perforation: poor insertion technique or <4wks post-partum.

•Dysmenorrhoea.

Timing of IUCD insertion

•Insert any time during cycle (as long as pregnancy excluded).

•Post-partum: safe to insert IUCD from 4wks after delivery.

•Following TOP: insert within first 48h after termination.

•Switching from other contraception: any time as long as not pregnant.

OTHER FORMS OF CONTRACEPTION 629

Contraindications to copper-bearing IUCD

•Pregnancy.

•Undiagnosed genital tract bleeding.

•Active genital tract infection or PID.

•Uterine anomalies or fibroids distorting cavity.

•Copper allergy.

Levonorgestrel-releasing system (Mirena® IUS)

The LNG-releasing system has a T-shaped rod containing 52mg LNG (20 micrograms released daily). It is a reversible, highly effective contraceptive with a failure rate of 0.18 per 100 woman-years.

Due to its progestagenic content, menstrual blood loss is decreased by >90%, and it is as effective as endometrial ablation in the management of menorrhagia at 1yr.

Mode of action

•It acts on the endometrium, leading to endometrial atrophy and preventing implantation.

•Thickened cervical mucus inhibits sperm penetration.

2It is particularly useful when oestrogen is contraindicated.

•May be used in patients with a history of breast cancer: no disease for 5yrs and after consultation with breast surgeon.

•Breast-feeding: can be inserted 4 or more weeks post-partum.

Side effects

•Irregular PV bleeding is common in the first 3–4mths: amenorrhoea in up to 30% by 1yr.

•Hormonal symptoms: nausea, headache, breast tenderness, bloating.

630 CHAPTER 20 Contraception

Emergency contraception

Emergency contraception (EC) is licensed for use to protect women from unwanted pregnancy following UPSI or contraceptive failure.

The two main forms are:

•Oral EC—LNG or ulipristal (ellaOne®).

•Copper IUCD EC.

Levonogestrel (LNG EC)

•Consists of a single oral dose of 1.5mg of LNG.

•If taken within 72h of unprotected coitus it is estimated to prevent 85% of expected pregnancies.

•It may be used up to 120h after, but efficacy is uncertain and it is not licensed for use after 72h.

•It may also be used more than once in a cycle if clinically indicated.

•It does not provide contraceptive cover for the remainder of the cycle, another method of contraception must be used.

Side effects

•Nausea is common after ingestion.

•Vomiting only affects 1%.

•If a woman vomits within 2h of ingestion, she should take a further dose as soon as possible.

•Erratic PV bleeding is common in the first 7 days following treatment.

Ulipristal

•Progesterone receptor modulator.

•Licensed for use within 120h of UPSI.

•Can only be used once per cycle.

•Due to mode of action may impair the effectiveness of progestagencontaining contraceptives for the remainder of the cycle and so alternative contraceptive methods are advised.

Copper IUCD

•IUCD acts as an emergency contraceptive by inhibiting fertilization by direct toxicity.

•Affects implantation by inducing an inflammatory reaction in the endometrium.

•The copper content may also inhibit sperm transport.

•IUCD EC can be inserted within 120h following UPSI.

•Failure rates are less than 1%.

The risks and complications for IUCD EC are similar to IUCD use in general. It can be removed after the next menstruation provided that no unprotected coitus has occurred since menstruation, or retained for ongoing contraception.

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FEMALE STERILIZATION: PREOPERATIVE CONSIDERATIONS 633

Women at higher risk of regret

Care must be taken when considering sterilization for women from the following groups, as they are more likely to have regret and present requesting reversal:

•Under the age of 30yrs: current RCOG recommendation to avoid.

•Who do not have children.

•Who decide during pregnancy.

•Who have had recent relationship loss.

634 CHAPTER 20 Contraception

Female sterilization: the procedure

Preoperative—mandatory checklist

•Document LMP.

•Check current contraception has been used to date.

•Pregnancy test must be performed (a negative test does not exclude the possibility of a luteal phase pregnancy).

•If any doubt exists about certainty of wishes or risk of pregnancy, the procedure should be abandoned.

Intraoperative

•Day case laparoscopic procedure is associated with quicker recovery rates and less morbidity than mini-laparotomy.

•Usually general anaesthesia, but local anaesthesia is an acceptable alternative.

•Laparascopic mechanical occlusion of the tubes by either Filshie clips or rings: diathermy ithe risk of ectopic pregnancies and is less easy to reverse.

•When a mini-laparotomy is used, any effective surgical or mechanical method of tubal occlusion can be used (a modified Pomeroy procedure may be preferable for post-partum sterilization or at the time of CS due to lower failure rates).

Postoperative

•The patient must be informed about the method of occlusion used and any procedural complications.

•She must be advised to use effective contraception till her next menstrual period.

Special circumstances

•Tubal occlusion should ideally be performed after an appropriate interval following pregnancy.

•Sterilization post-partum or post-abortion carries a higher risk of regret and possibly increased failure rates.

•In cases of sterilization at the time of CS, counselling and consent should be taken at least 1wk before the procedure.

Newer techniques

Hysteroscopic methods for sterilization are still under evaluation. Essure is the only form of hysteroscopic tubal occlusion licensed for use in the UK at present. It involves placing a metal micro-insert in the fallopian tubes under hysteroscopic guidance. This causes tubal blockage by subsequent fibrosis. A hysterosalpingogram is usually done 3mths after the operation to confirm tubal blockage.