Babies Tale

Contraceptive methods are only very rarely a cause of infertility. The interuterine device (IUD) can increase a woman’s chance of suffering from pelvic inflammatory disease (PID), which can lead to infertility. The contraceptive pill sometimes leads to a condition called post-Pill amenorrhoea, in which a woman’s periods do not return when she stops taking the Pill. Research has shown that this condition lasts for a maximum of two years after Pill use. It can also be treated with drugs.

A woman used to taking the Pill for several years, or using an IUD or cap regularly and worrying every time her period is late, may well expect to get pregnant as soon as she stops using her chosen contraception. But often she does not. This does not necessarily mean she is infertile. However, as a woman gets older her fertility declines. Using contraception for years may mean she is less fertile by the time she stops and tries to get pregnant. Also, using contraception, and particularly the Pill, can disguise infertility problems for years. The Pill usually means that a woman has a regular cycle; she may not realize she is not ovulating.

Hormonal Problems

One of the most common causes of infertility in women is a malfunctioning of the complex hormonal interactions that govern a woman’s menstrual cycle. The woman’s monthly cycle is controlled by the pituitary gland in the brain which, in tum, is governed by another gland called the hypothalamus. The pituitary produces a follicle-stimulating hormone (FSH), which controls the production of the hormone estrogen by the ovary. It also prepares one of the follicles inside the ovary to release the egg. A second pituitary hormone, luteinizing hormone (LH), enables the ovary to release its egg. Estrogen causes the lining of the womb to thicken in readiness to receive the fertilized egg.

If the egg is not fertilized, the corpus luteum begins to shrink, levels of estrogen and progesterone decrease, the lining of the womb disintegrates and menstrual bleeding results. Falling levels of estrogen and progesterone stimulate the pituitary to produce more FSH, and the cycle begins again.

If the egg is fertilized, however, and implants into the womb, the corpus lute urn continues to produce estrogen and progesterone until the placenta attaching the fetus to the wall of the womb is mature enough to produce the necessary hormones itself.

Failure to ovulate is normally caused by the woman’s body’s failure to produce enough of the pituitary hormones, or by their release at the wrong time. Since the pituitary is ultimately controlled by the hypothalamus, anything that affects the hypothalamus can also affect this gland. The hypothalamus can be affected by severe physical and emotional stress, as many women know when the stress of travel, work, illness or emotional turmoil disrupts their menstrual cycle. As women age, fewer menstrual cycles actually involve ovulation, so that in her early forties as few as one in every two or three cycles will produce an egg.

Treatment

Help for women unable to ovulate has been available for many years in the form of fertility drugs. There are two main types: those that prod the pituitary into producing FSH and LH on time and those that replace FSH and LH if this approach fails.

Clomiphene citrate (Clomid’P) is an artificial drug that triggers the release of FSH and LH in the pituitary. It seems to induce ovulation in about 80% of women treated with it, though not all will succeed in getting pregnant. One reason for this is that clomiphene tends to prevent the cervical mucus from becoming fluid at the fertile time in the month to enable the sperm to enter the womb. This problem can sometimes be overcome by giving estrogen as well in the few days before ovulation.

Sometimes a combination of clomiphene and human chorionic gonadotrophin (HCG, a hormone produced by the placenta and young embryo) given on the fourteenth day of the cycle will induce women to ovulate who would not do so on clomiphene alone. Clomiphene also seems to help women with a progesterone deficiency. It has been in use for many years and is considered safe, although a few women do have unpleasant side effects, such as nausea, a bloated feeling, or very rarely, enlargement of the ovaries accompanied by pain in the pelvis. Some infertility specialists deny the severity of these symptoms, or fail to inform women of them. Severe symptoms may indicate over-stimulation of the ovaries.

Recently there has been some concern that clomiphene citrate might cause more eggs, which have chromosomal abnormalities, to be released following its use. Others have questioned whether there might be other long-term effects on the children who are conceived after their mothers took fertility drugs, as happened with the children of women who took the drug DES (diethylstilbestrol) in early pregnancy to prevent a miscarriage. This is of particular concern to women who take large doses of fertility drugs to make them produce more than one egg, as is done for IVF and other treatments. However, there is no evidence to support such fears yet.

Human menopausal gonadotrophin (HMG), trade name Pergonalf and Humegonw, is a hormone extracted from the urine of pregnant women. It stimulates the follicles containing the egg. HMG is usually given as a daily injection, followed by the injection of another drug, HCG, which actually triggers ovulation. About 90% of women will ovulate with this treatment, though again, not all will conceive and some will miscarry. About 20% to 30% of pregnancies resulting from this treatment will be multiple births. HMG is responsible for most of the multiple pregnancies that occur with fertility drugs.

The hormone HMG is potent and may over-stimulate the ovaries, so the level of estrogen in the blood must be monitored daily and the follicles are often monitored by ultrasound. A new development, which might overcome this problem, is a small “pump” about the size of a wallet that, attached to the woman’s arm, provides small, even doses of hormone through a fine needle. However, having a pump attached day and night and having to have the needle repositioned when necessary can be unpleasant.

Some women do not ovulate because their blood contains a high level of a hormone called prolactin, which is normally produced in quantity only while breastfeeding and which tends to prevent ovulation. For women with this problem there may be hope with a drug called bromocriptine. Bromocriptine prevents the pituitary from producing prolactin, and after treatment ovulation occurs in about 95% of women who previously produced too much.

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