Family Doctor Books


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Family Doctor Books
Preview of Understanding Infertility

Absolute infertility, or sterility, with no chance of natural conception is very rare. It occurs only if, for example, the man is not producing sperm, the woman has had a premature menopause and has no eggs remaining in her ovaries, or both of the woman’s fallopian tubes are blocked (pre-venting sperm from reaching her eggs). These problems can often be overcome with fertility treatments.

Most fertility problems, how-ever, are in fact low fertility, or subfertility, where a couple has been trying to conceive for some time without success. How long is ‘some time’? This depends on a number of factors, particularly the woman’s age and whether there are other reasons to suspect a fertility problem.

Most of us were told as teenagers, by well-meaning parents and teachers, that getting pregnant was very easy unless we used a reliable form of contraception. In fact, compared with most other animal species, humans have relatively poor natural fertility. In young fertile couples, the highest chance of conceiving in each monthly cycle, when they first start to try, is only 33 per cent (one in three), or throwing a six with two dice.

For young fertile couples, the chance of conceiving may be as high as one in three (33 per cent), or throwing a six with two dice.
For most couples, the chance of conceiving is on average one in six (17%), or throwing a six with one dice.

For most couples, the chance of conceiving is lower than this, on average a one in five or six chance each month – about the same chance as throwing a six with a dice.

Just like throwing a six, the chance of pregnancy increases with the number of monthly cycles a couple has been trying. Fifty per cent of couples who are fertile will have conceived by three months, 75 per cent by six months and 90 per cent by twelve months. By two years, this has increased only slightly to 95 per cent.

In general, you should consult your doctor if you have not conceived within one year of trying, and certainly after two years. However, this does not take account of the woman’s age. A woman’s natural fertility starts to reduce from her late 20s – slowly at first, more rapidly after the age of 35 and very sharply after the age of 40. This is mainly a result of the reduction in the quality of the eggs remaining in her ovaries.

Not only does a woman’s chance of achieving a pregnancy decrease as she gets older, but also her risk of miscarriage increases if she does conceive. This is probably related to the quality of her eggs and the resulting embryo rather than any problem with the lining of her uterus. In addition, the risk of conceiving a child affected by a chromosome abnormality (such as Down’s syndrome) rises progressively after a woman reaches the age of 35. Therefore, if the woman is over 35, couples should seek expert advice promptly if they have not conceived within one year. If the woman has reached 40 years of age, they should seek advice after six months.

There are many other reasons why some couples should seek help even earlier. For the man, this may be a past infection of his testes (orchitis) or surgery (perhaps to correct the failure of his testes to descend properly into his scrotum in childhood). For the woman, this may be irregular or infrequent periods, previous pelvic infection, severe appendicitis or abdominal surgery (perhaps to remove an ovarian cyst). For more on this, see ‘Why can’t we conceive?’.

Seeking advice

Some couples delay seeking medical advice because they are finding it difficult to accept that they may have a problem or because they are concerned that they will be asked questions about personal and private aspects of their lives. Your GP and the staff at a fertility clinic will be aware of these feelings. They are familiar with the anxieties and fears about the investigations, the problems that they may find and the treatment options. The information that they will give you will enable you to decide whether and how you wish to proceed. Delay in seeking advice may limit the treatment options that may be available or their chance of success.

Even if you seek medical advice because of infertility, it does not necessarily follow that you will need any treatment to improve your chance of pregnancy. Some couples find that they have conceived while waiting for a clinic appointment or during the course of their blood tests and other investigations. Many others find that the results of the various tests are all normal. If you have been trying to conceive for a relatively short time, you may simply be reassured by the clinic that your chance of pregnancy remains high, and you may be advised to return for a review appointment if you have not been successful after a few more months. In addition, some investigations, such as those to check that your fallopian tubes are open, may temporarily enhance fertility.

You may be concerned that all you will be offered are expensive, high-technology infertility treat-ments, such as in vitro fertilisation (IVF). This is understandable given the huge amount of media interest that these treatments have attracted. However, many of the potential causes of infertility can be corrected with much simpler treatments, such as drug therapy.

Is infertility on the rise?

The brief answer is no. However, there has been a large increase in the number of couples seeking specialist help over the past 15 years. This is partly because there is now a greater awareness about the increasing range and effectiveness of infertility treatments. The increased media attention has made infertility less of a taboo, which means that friends and acquain-tances may be more open in talking about their own experiences of fertility problems.

Many couples now delay having children. This may be for the woman to pursue her career, or for a couple to achieve greater financial stability or pursue other ambitions before having a family. Twenty-five years ago, the average age for a woman to have her first child was in her early 20s, a decade ago it was 25 years, now it is 28 years. This delay, to an age at which the woman’s natural fertility is starting to reduce, inevitably means that more couples will experience difficulty in conceiving and will seek medical advice. Research from the USA shows that, in more than half the couples seen at infertility clinics, the woman is over 35. By this age, natural fertility is reducing rapidly, and many couples may need to consider more effective (but also more stressful and expensive) high-technology treatments to optimise their chance of pregnancy.

The question of whether men’s fertility is declining is also important. There have been several reports recently in the media and scientific press suggesting that sperm counts are falling. Some of these have looked at results over time and have found a fall in overall sperm numbers. Others have found no change, and some have even found an increase within their own laboratory. It may be that, as examination techniques have become more rigid, the actual sperm counts being reported are lower.

On the other hand, the reported trends may reflect a real fall in sperm numbers, possibly as a result of toxins (poisons) in the environment and the increasing use of steroid hormones in food production. At present, the scientific community does not believe there is any great cause for concern, as the evidence for a reduction in sperm counts is not particularly strong. However, this issue is not yet resolved.