Sexual and reproductive health

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Sexual and reproductive health

Roger Pepperell

Contraception and termination of pregnancy

The ability to control fertility by reliable artificial methods has transformed both social and epidemiological aspects of human reproduction. Family size is determined by a number of factors, including social and religious customs, economic aspirations, knowledge of contraception and the availability of reliable methods to regulate fertility.

Artificial methods of contraception act predominantly by the following pathways:

The effectiveness of any method of contraception is measured by the number of unwanted pregnancies that occur during 100 women years of exposure, i.e. during 1 year in 100 women who are normally fertile and are having regular coitus. This is known as the ‘Pearl index’ (Table 19.1).

Table 19.1

Failure rates per 100 women for different methods of contraception

  USA data used by WHO: % of women having an unintended pregnancy within the first year of usea Oxford/FPA Study (all women married and aged above 25)b
Typical use* Perfect use Overall (any duration) Age 25–34 (≤2 years use) Age 35+ (≤2 years use)
Sterilization
 Male (after azoospermia) 0.15 0.1 0.02 0.08 0.08
 Female (Filshie clip) 0.5 0.5 0.13 0.45 0.08
Subcutaneous implant 0.05 0.05
 Nexplanon®          
Injectable (DMPA) 3 0.3
Combined pills
 50 µg oestrogen 8 0.3 0.16 0.25 0.17
 <50 µg oestrogen 8 0.3 0.27 0.38 0.23
Evra® patch 8 0.3
NuvaRing® 8 0.3
Cerazette® progestogen-only pill   0.17
Old-type POP 8 0.3 1.2 2.5 0.5
IUD
 Levonorgestrel-releasing intrauterine system (LNG-IUS) 0.2 0.2
T-Safe® Cu 380 A 0.8 0.6
 Other >300 mm copper-wire IUDs (Nova-T 380®, Multiload® 375, Flexi-T® 300) ≈1 ≈1
Male condom 15 2 3.6 6.0 2.9
Female condom 21 5
Diaphragm (all caps believed similar, not all tested) 16 6 1.9 5.5 2.8
Withdrawal 27 4 6.7
Spermicides alone 29 18 11.9
Fertility awareness 25        
 Standard days method 5 15.5
 Ovulation (mucus) method 3–4
 Persona 6
 No method, young women 80–90
 No method at age 40 40–50
 No method at age 45 10–20
 No method at age 50 (if still having menses) 0–5

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Sources: aTrussell J (2007) Contraceptive efficacy. In: Hatcher RA, Trussell J, Nelson AL, et al. (eds). Contraceptive technology: nineteenth revised edition. Ardent Media, New York.

Other Notes (1) Note influence of age: all the rates in the fifth column being lower than those in the fourth column. Lower rates still may be expected above age 45. (2) Much better results also obtainable in other states of relative infertility, such as lactation. (3) Oxford/fpa users were established users at recruitment – greatly improving results for barrier methods (Qs 1.19, 4.9). (4) The Nexplanon, Cerazette and Persona results come from pre-marketing studies by the manufacturer, giving an estimate of the Pearl ‘method-failure’ rate.

bVessey M, Lawless M, Yeates D (1982) Efficacy of different contraceptive methods. Lancet 1(8276):841–842.

*Typical use: Among typical couples who initiate use of the method (not necessarily for the first time), the percentage who experience an accidental pregnancy during the first year if they do not stop use for any other reason.

Perfect use: Among typical couples who initiate use of the method (not necessarily for the first time), and who then use it perfectly (both consistently and correctly), the percentage who experience an accidental pregnancy during the first year if they do not stop use for any other reason.

Data not available from Trussell, so best alternative data given, e.g. from manufacturer’s studies.

(This Table was published in Guillebaud J, MacGregor A (2013) Contraception 6e. ©Elsevier. Reproduced from Trussell J, Wyn LL (2008) Reducing unintended pregnancy in the United States. Contraception 77(1): 1–5, with permission.)

Barrier methods of contraception

These techniques involve a physical barrier that reduces the likelihood of spermatozoa reaching the female upper genital tract. Barrier methods also offer protection against sexually transmitted infection (STIs). The relative risk of an STI-induced pelvic inflammatory disease (PID) is 0.6 for women using these methods. Women who use another method of contraception to prevent pregnancy are often advised to use a condom as well to reduce an otherwise increased risk of STI.

Male condoms

The basic condom consists of a thin, stretchable latex film, which is moulded into a sheath, lubricated and packed in a foil wrapper. The sheath has a teat end to collect the ejaculate. The disadvantages of sheaths are that they need to be applied before intercourse and that they reduce the level of sensation for the male partner. The advantages are that they are readily available, are without side effects for the female partner and provide a degree of protection against infection. They have an efficiency of 97–98% with careful use, although typical failure rates can be as high as 15 pregnancies per 100 women years. Common reasons for failure are leakage of sperm when the penis is withdrawn, putting the condom on after genital contact, use of lubricants that cause the latex to break and mechanical damage. Condoms should be unrolled completely on to the penis before genital contact occurs and held when the penis is withdrawn to avoid leakage. The penis needs to be withdrawn from the vagina before the erection is lost, or sperm will inevitably be lost from it.

Diaphragms and cervical caps

The modern vaginal diaphragm consists of a thin latex rubber dome attached to a circular metal spring. These diaphragms vary in size from 45–100 mm in diameter. The size of the diaphragm required is ascertained by examination of the woman. The size and position of the uterus are determined by vaginal examination and the distance from the posterior vaginal fornix to the pubic symphysis is noted. The appropriate measuring ring, usually between 70 mm and 80 mm, is inserted. When in the correct position the anterior edge of the ring or diaphragm should lie behind the pubic symphysis and the lower posterior edge should lie comfortably in the posterior fornix (Fig. 19.1).

The woman should be advised to insert the diaphragm either in the dorsal position or in the kneeling position while bending forwards. The diaphragm can be removed by simply hooking an index finger under the rim from below and pulling it out. The diaphragm should be smeared on both sides with a contraceptive cream, and it is usually advised that it should be inserted dome down. However, some women prefer to insert the diaphragm with the dome upwards.

The diaphragm must be inserted prior to intercourse and should not be removed until at least 6 hours later. The main advantage of this technique is that it is free of side effects to the woman, apart from an occasional reaction to the contraceptive cream. The main disadvantages are that the diaphragm must be inserted before intercourse and typical failure rates are between 6 and 16 pregnancies per 100 women years. The main reason for failure is probably that the diaphragm size chosen is actually too small and when orgasm occurs in the woman, when the vaginal size can increase dramatically, the diaphragm no longer fits adequately.

There are a variety of vault and cervical caps, which are of much smaller diameter than the diaphragm. These are suitable for women with a long cervix or with some degree of prolapse, but otherwise have no particular advantage over the diaphragm.

Spermicides and sponges

Spermicides are only effective, in general, if used in conjunction with a mechanical barrier. Pessaries or suppositories have a water-soluble or wax base and contain a spermicide. They must be inserted approximately 15 minutes before intercourse. Common spermicides are nonoxynol-9 and benzalkonium. Creams consist of an emulsified fat base and tend not to spread. Care in insertion is essential so that the spermicide covers the cervix.

Jellies or pastes have a water-soluble base that spreads rapidly at body temperature. They therefore have an advantage over creams, as they spread throughout the vagina.

Foam tablets and foam aerosols contain bicarbonate of soda so that carbon dioxide is released on contact with water. The foam spreads the spermicide throughout the vagina. Pregnancy rates vary with different agents, but average around 9–10 per 100 women years.

Sponges consist of polyurethane foam impregnated with nonoxynol-9. The failure rate is between 9% and 32%, and their use in isolation is therefore not recommended. They are inserted at least 15 minutes before intercourse and can be left in for a maximum of 12 hours.

Intrauterine contraceptive devices

Intrauterine contraception is used by 6–8% of women in the UK. A wide variety of intrauterine devices (IUDs) have been designed for insertion into the uterine cavity (Fig. 19.2). These devices have the advantage that, once inserted, they are retained without the need to take alternative contraceptive precautions. It seems likely that they act mainly by preventing fertilization. This is a result of a reduction in the viability of ova and the number of viable sperm reaching the tube.

The first device to be widely used was the Graefenberg ring, which was made of a silver–copper alloy. Introduced in the 1930s, it ran into considerable difficulties with haemorrhage, infection, miscarriages and uterine perforation. Later, inert plastic devices such as the Lippes loop were associated with a significant increase in menstrual blood flow in many users. The development of copper IUDs has been associated with improved contraceptive efficacy and a lessening of excess menstrual blood loss.

Types of devices

The devices are either inert or pharmacologically active.

Devices containing progestogen

The levonorgestrel-releasing intrauterine system or Mirena® contains 52 mg of levonorgestrel (Fig. 19.2) which suppresses the normal build up of the endometrium so that, unlike most IUDs, it causes a reduction in menstrual blood loss. However, there is a high incidence of irregular scanty bleeding in the first 3 months after insertion of the device. Unlike previous progestogen-containing devices it does not appear to be associated with a higher risk of ectopic pregnancy. The superior efficacy of third-generation copper IUDs and the levonorgestrel-releasing system means that these are now considered the devices of choice.

Insertion of devices

The optimal time for insertion of the device is in the first half of the menstrual cycle. With postpartum women, the optimal time is 4–6 weeks after delivery. Insertion at the time of therapeutic abortion is safe and can be performed when motivation is strong. It is unwise to insert IUDs following a miscarriage because of the risk of infection. Devices may be inserted within a few days of delivery but there is a high expulsion rate.

Ideally, the woman should be placed in the lithotomy position. A cervical smear should be taken, and a swab taken for culture if there is any sign of infection. The uterus is examined bimanually and its size, shape and position are ascertained. The cervix is swabbed with an antiseptic solution and a vulsellum can be applied to the anterior lip of the cervix, although this is not essential and may cause discomfort.

The passage of a uterine sound will indicate the depth and direction of the uterine cavity and the dimensions of the cavity may be assessed by devices known as cavimeters, which measure its length and breadth. Many IUDs are available in different sizes, and cavimeters help to choose the appropriate IUD.

Insertion devices vary in construction but generally consist of a stoppered plastic tube containing a plunger to extrude the device, which may be linear or folded. The device is inserted in the plane of the lumen of the uterus and care must be taken not to push it through the uterine fundus.

Attempts at insertion of a device where the cervical canal is tight may result in vagal syncope. Acute pain following insertion may indicate perforation of the uterus. The woman should be instructed to check the loop strings regularly and to notify her doctor immediately if the strings are not palpable.

Complications

The complications of IUDs are summarized in Figure 19.3.

Perforation of the uterus

About 0.1–1% of devices perforate the uterus. In many cases, partial perforation occurs at the time of insertion and later migration completes the perforation. If the woman notices that the tail of the device is missing, then it must be assumed that one of the following has occurred:

If there is no evidence of pregnancy, an ultrasound examination of the uterus should be performed. If the device is located within the uterine cavity (Fig. 19.4A), unless part of the loop or strings is visible, it will generally be necessary to remove the device with formal dilatation of the cervix under general or local anaesthesia. If the device is not found in the uterus, a radiograph of the abdomen will reveal the site in the peritoneal cavity (Fig. 19.4B). It is advisable to remove all extrauterine devices by either laparoscopy or laparotomy. Inert devices can probably be left with impunity, but copper devices promote considerable peritoneal irritation and should certainly be removed.

Pelvic inflammatory disease

Pre-existing PID is a contraindication to this method of contraception. There is a small increase in the risk of acute PID in IUD users, but this is largely confined to the first 3 weeks after insertion. If PID does occur, antibiotic therapy is commenced and, if the response is poor, the device should be removed. If the infection is severe, it is preferable to complete 24 hours of antibiotic therapy before removing the device. It is not uncommon to find evidence of Actinomyces organisms in the Pap smear routinely collected in an asymptomatic woman who has an IUD in place. This is generally not due to an actinomycotic pelvic infection, but due to the presence of these organisms on the surface of the IUD. There is no absolute consensus of what should be done if such organisms are found in the Pap smear. Some would remove the IUD, repeat the smear in 3 months and reinsert another IUD if the smear is clear, whereas others would leave the IUD in place but give a 2 week course of penicillin therapy.

Hormonal contraception

Oral contraception is given as a combination of oestrogen and progestogen, as a combined pill, or as progestogen only.

Combined pill

Most of the current combined pills contain 20–30 µg of ethinyl oestradiol and 150–4000 µg of progestogen. The progestogens used are derived from 17-hydroxyprogesterone or 19-norsteroids (Box 19.1).

The pill is usually taken for 21 days, followed by a 7-day pill-free interval during which there is a withdrawal bleed. Everyday (ED) preparations include seven placebo pills that are taken instead of a pill-free week. The concentration of the hormones may be the same throughout the 21 days (monophasic preparations) or vary across the cycle (biphasic and triphasic preparations) in order to reduce breakthrough bleeding.

Contraindications

There are various contraindications to the pill, some being more absolute than others.

The absolute contraindications include pregnancy, previous pulmonary embolism or deep vein thrombosis, sickle-cell disease, porphyria, current active liver disease or previous cholestasis (particularly where it is associated with a previous pregnancy), migraine associated with an aura or carcinoma of the breast. It is necessary to maintain a high level of vigilance in women with varicose veins, diabetes, hypertension, renal disease and chronic heart failure but none of these conditions constitutes an absolute contraindication and, in some cases, the adverse effects of a pregnancy may substantially outweigh any hazard from the pill. Women who smoke and are also over the age of 35 years have a significantly increased risk of coronary artery and thromboembolic disease.

The occurrence of migraine for the first time, severe headaches or visual disturbances, or transient neurological changes are indications for immediate cessation of the pill. There are a series of minor side effects that may sometimes be used to advantage or may be offset by using a pill with a different combination of steroids (Table 19.2).

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Major side effects

The risk of venous thrombosis is increased from 5/100 000 to 15/100 000 women per year and is further increased in smokers and women with a previous history of venous thrombosis. This compares to a risk in pregnancy and the puerperium of 60/100 000 women. Several studies have suggested that so-called ‘third and fourth-generation’ combined pills containing desogestrel, gestodene or drospirenone, are associated with a twofold greater risk of venous thrombosis than those containing other progestogens, although the risk of venous thrombosis was lower in these studies than had previously been reported.

There is an increase in arterial disease, with a 1.6 to 5.4-fold increase in stroke and 3 to 5-fold increase in myocardial infarction (although there is no significant increase in women under 25 or in non-smokers). However, both these conditions are rare in women under the age of 35 years so the overall risk remains low, with deaths from venous thrombosis attributable to the combined pill of no more than 1–2/million women years.

Although some reports have suggested there is a small increase in the relative risk of breast (relative risk 1.24) and cervical cancer (relative risk 1.5–2) in pill users, especially if it is commenced before a first pregnancy, the breast cancer increased risk is not definitely proven, and the cervical cancer risk is probably due to the incidence of wart virus infection and not the taking of the oral contraceptive pill (OCP).

There is an increase in gallstone formation and cholecystitis and an increase in glucose intolerance.

The progestogen-only pill has a higher failure rate and is more likely to be associated with irregular bleeding. If it fails there is a higher risk of ectopic pregnancy.

Beneficial effects

In addition to the prevention of unwanted pregnancy, the use of the combined pill is associated with a 30% reduction in blood loss at menstruation, a lower incidence of ectopic pregnancy (0.4/1000) and some protection against PID and benign ovarian cysts. Pill users also have a reduced risk of both endometrial and ovarian cancer of up to 50%, depending on the length of use with this benefit lasting for up to 10 years after the OCP therapy has been ceased.

imagePractical patient care of a patient requesting to use the combined OCP

It is important to obtain a complete general history and examination before prescribing the pill, and also to perform annual check-ups and cervical cytology. There are a large number of compounds commercially available, and some pills are marketed by different companies but contain the same compounds at the same concentrations. The history taken must exclude the contra-indications detailed above. Examination should include breast examination, blood pressure assessment and, except in women who have never been sexually active, speculum examination, Pap smear testing, and PV assessment. An appropriate pill for that particular patient should then be chosen, and counselling then given along the following lines.

Which pill should you choose?

In general a 30 µg ethinyl oestradiol-containing pill is usually chosen first because of its effectiveness and low cost. The 20 µg containing preparations are much more expensive but preferred by many women, and the side effects are usually less, except that breakthrough bleeding during the first few months of treatment is more common. If the woman had evidence of androgen excess, hirsutism or clinical PCOS, the OCP Diane 35 should be given because its progestogen is cyproterone acetate, an anti-androgen. If the woman has fluid retention problems, an OCP containing drospirenone is usually advisable.

If the woman has used the OCP previously and had major problems with breakthrough bleeding, has conceived when taking the pill correctly, or is on treatment with an anti-epileptic medication, it is safer to advise them to take an OCP containing 50 µg of ethinyl oestradiol.

When should it be commenced?

It is best commenced on day 2–3 of the next period but can be commenced at any time. Many combined pills include 7 days of placebo (‘sugar’) tablets so that the user takes a pill every day of the month and so reduces the risk of forgetting when to restart the pill after the normal 7 ‘pill free’ days each cycle (sometimes labelled ‘ED’ or everyday preparations). Each tablet including the placebos are labelled with a day of the week in these calendar packs with the placebos being a different colour (Fig. 19.5) With these pills a woman should start taking the pill on the first day of her next period starting with the inactive tablet corresponding to the current day of the week. When changing from a higher to a lower dose pill preparation women should be advised to start taking the active tablets of the new pill immediately on completing the last tablet of her previous pill, omitting the normal 7 day gap.

When is further review needed and why?

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