The combined oestrogen-progestogen pill is widely used for contraception and has a low failure rate « 1 per 100 woman-years). ‘Pills’ contain 20-50 J.Lgof oestrogen, usually ethinyloestradiol, together with a variable amount of one of several progestogens.
The mechanism of action is twofold:
Suppression by oestrogen of gonadotrophins, thus preventing follicular development, ovulation and luteinization 2 Progestogen effects on cervical mucus, making it hostile to sperm, and on tubal motility and the endometrium Side-effects of these preparations; most of the serious ones are rare and are less common on modern 20-30 J.Lgoestrogen pills.
While some problems require immediate cessation of the pill, the importance of other milder side-effects must be judged against the hazards of pregnancy occurring with inadequate contraception, especially if other effective methods are not practicable or acceptable. It is clear, however, that the hazards of the combined pill are greater in women over 35 years, especially in smokers and those with other risk factors for cardiovascular disease (e.g. hypertension, hyperlipidaemias). The ‘mini-pill’ (progestogen only) is less effective but is often suitable where oestrogens are contraindicated. A progesterone antagonist, mifepristone, has recently been introduced which, in combination with a prostaglandin analogue, induces abortion of pregnancy up to 9 weeks’ gestation. It prevents progesteroneinduced inhibition of uterine contraction.
Loss of libido
Increased growth rate of some malignancies
Increased blood pressure”
Deep vein thrombosis’
Nausea and vomiting
Abnormal liver biochemistry’
Possible increase in cancer of the breast
Increased dotting tendency
Impaired glucose tolerance
Worsened lipid profile
Drug interactions (reduced contraceptive effect due to enzyme induction)
‘Common reasons for stopping oral contraceptives.
This term, kinder than infertility, is defined as the inability of a couple to conceive after 1 year of unprotected intercourse. Investigation requires the combined skills of gynaecologist, endocrinologist and, ideally, andrologist. Both partners must be considered and every aspect of the physiology critically examined.
MALE FACTOR. About 30–40% of couples have a major identifiable male factor.
FEMALE FACTORS. Female tubal problems account for perhaps 20%; a similar proportion have ovulatory disorders.
UNCOMMON CAUSES. Inadequate intercourse, hostile cervical mucus and vaginal factors are uncommon (5%).
‘IDIOPATHIC’-15% have no apparent explanation.
BOTH PARTNERS. A significant proportion have both male and female problems.
The major factors involved in subfertility and their investigation. SCMC, sperm-cervical mucus contact test.
Both partners should be seen, not just the woman, and the following factors checked: THE MAN: previous testicular damage (e.g. orchitis, trauma, undescended testes), urethral symptoms and venereal problems, local surgery and use of alcohol and drugs. A semen analysis early in the investigations is essential.
THE WOMAN: previous pelvic infection, regularity of periods, previous surgery, alcohol intake and smoking. Adequacy of body weight.
TOGETHER: frequency and adequacy of intercourse, use of lubricants.
Examination should include an assessment of secondary sexual characteristics, body habitus and general health. In men, size and consistency of the testes are important, plus exclusion of a varicocele. In women, vaginal examination allows a check on the uterus and ovaries.
Appropriate tests for particular defects.
Counselling of both partners is essential. Any defect(s) found should be treated if possible. Ovulation can usually be induced by exogenous hormones if simpler measures fail, while in vitro fertilization (IVF) and similar techniques are becoming more widely used, especially where there is tubal blockage, oligospermia or ‘idiopathic subfertility’ .
DISORDERS OF SEXUAL DIFFERENTIATION
An individual’s sex can be defined in several ways:
CHROMOSOMAL SEX. The normal female is 46XX, the normal male 46XY. The Y chromosome confers male sex; if it is not present, development follows female lines.
GONADAL SEX. This is obviously determined predominantly by chromosomal sex but requires normal embryological development.
PHENOTYPIC sex=-the normal physical appearance and characteristics of male and female body shape. This in turn is a manifestation of gonadal sex and subsequent sex hormone production.
SOCIAL SEX (GENDER) -heavily dependent on phenotypic sex and normally assigned on appearance of the external genitalia at birth. SEXUAL ORIENTATION-heterosexual, homosexual (male/male or female/female) or bisexual (both sexes).
Recent studies suggest that there may be some element of genetic determination of homosexuality. Disorders of sexual differentiation are rare but may affect chromosomal, gonadal, endocrine and phenotypic development.