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Q1: I am a 39 yr old mother of one much loved son born eight years ago. Since then we have tried to conceive again with no luck - we have never used contraception. After trying again for years I miscarried four years ago but have endured the pain of infertility since, including two cycles of icsi/ivf. After being told i had no problems we were then told four years ago my husbands sperm count is 97per cent abnormal and that i won't conceive without ivf, it hasnt improved any since despite spending money on supplements etc. We are heartbroken and confused, my husband is healthy, doesnt smoke or drink to excess, how can his sperm count deteriorate so rapidly after having conceived one healthy baby? If we knew why it would be easier to bear, and does the quality of sperm cause miscarriage? Please help time is running out for us. Name withheld, Maidstone, Kent.

A1: Since Biblical times it has been the custom to blame the woman in a partnership for infertility. There are plenty of quotes in the Bible about one woman or another being barren, but few if any about male infertility. It is only in the last fifty years that people have understood that the man is almost as likely as the woman to be either the responsible partner for infertility, or when a couple are infertile that both male and female may have less than an optimal chance of having a baby.

Until a year or two ago seminal analysis was comparatively rough and ready. Seminal volume, the number of sperm, the number of sperm that were abnormal when viewed down the microscope and their vitality and ability to swim fast in a straight line, rather than milling around aimlessly, were all factors that were taken into account.

Recently the likely efficiency of sperm has been measured by studying the sperm DNA and as a result the comprehensive semen analysis now gives a much better picture of a man's probable ability to impregnate. The advantage of the current tests are that they measure the genetic integrity of the sperm, this integrity is essential if a normal embryo is to develop normally. If the DNA is excessively fragmented the man may be infertile although the sperm count, the motility analysis and the assessment of the number of abnormal sperm are all normal.

Examination of sperm should now include the DNA fragmentation index. If it shows than less than 15 per cent of the sperm have evidence of DNA fragmentation specimen is classified as having excellent quality sperm. Between 15 and 30 per cent of sperm showing fragmentation results in this sperm being described as of good fertility potential. Over 30 per cent of fragmented sperm leads to the man's sperm being described as of fair to poor quality. Normal full term pregnancies are perfectly possible with a raised DNA fragmentation index, but these become less likely as the fragmentation index increases.

The factors that may affect the fertility of the male sperm, even though the sperm count is normal are :

A Persistent temperature from an illness and other chronic or acute infections. These infections include those with chlamydia or mycoplasma.
B Poor diet
C Cigarette smoking
D Varicocoeles (varicose veins) in the scrotum
E Increased testicular temperature - the old argument against tight trousers
F Environmental pollutants
G Drugs especially the so-called recreational drugs but any medicinal drugs a patient may be taking should also be reviewed.
H Advanced age of the man. This is interesting because the relationship between age, fertility and sperm count has been inconsistent and it has always been arguable whether increased age alone was a factor contributing to infertility. This new work done on DNA fragmentation may give the clue as to why about one in five older men have a reduced fertility, even though their sperm counts seem to be in good order. The infertility may well related to the increased DNA sperm fragmentation index.

In all cases of infertility I think it is now worthwhile having advanced tests on the actual sperm of a man as well as sperm count. I also think it is helpful if the woman has her ovarian studies done so that such factors as the Anti Mullerian Hormonal (AMH) may be assessed. If you have had IVF you will probably have had these tests carried out. Other women, especially those in their thirties, may also find it worthwhile to check out their ovarian state by having a full ovarian ageing profile. This measures three factors, the FSH (follicle stimulating hormone), the inhibin B levels and the AMH.

It is not unusual for men's sperm levels to alter from time to time. These changes may be temporary or sometimes, as after an attack of epidymitis, could be permanent. It is not unusual for men with a very low sperm count to father a child. Presumably you have tried the technique of IVF that involves injection of a single selected sperm into an ovum.

Q2: Can you tell me where I could get my partners sperm tested? We have had one pregnancy that ended in miscarriage and have tried IVF twice. The first time it didn't work and the second, it did but the embryo died at seven weeks. I seem to have no problem in producing eggs (25 during the last cycle, all fully mature) but am not sure why I can't conceive. I guess my eggs could have a genetic problem but so could my partners sperm. It would be good to get it tested so that we don't continue to waste time, energy and money and more goes at IVF. Thank you. Name and address withheld.