Surgery for women is primarily valuable when the fallopian tubes are blocked or damaged, preventing eggs from travelling from the ovaries to the womb. Success rates are now quite high and certainly much higher than for any other form of treatment for blocked tubes. The whole procedure has been improved in the last fifteen years by the advent of microsurgery. This is performed with very fine instruments under a microscope and means that operations can be much more precise, with consequently less damage to surrounding tissues and organs. The value of tubal surgery using microsurgical techniques is most easily illustrated with a diagram. This shows that success rates vary, depending on how severe the blockage is and where it is.
A completely blocked tube becomes filled with fluid and is known as hydrosalphinx. A surgical operation to open it, known as salpingostomy, has a success rate of twenty to twenty-five per cent.
A partially blocked fimbria can be further cleared by an operation known as fimbrioplasty, which carries a success rate of about forty per cent.
A blocked cornu can be cleared by an operation called cornual anastomosis, with success rates of about fifty-five per cent (success rates as reported by Hammersmith Hospital, London, measured in terms of successful pregnancies).
These figures, left unqualified, can be misleading. Many womens' tubes are blocked or damaged in more than one place and in this case the success rates may drop. For instance, the success rate for cornual anastomosis drops to around thirty per cent if the isthmus is also damaged.
These figures are also drawn from work at Hammersmith Hospital in London, which is a recognised world centre for tubal surgery using microsurgical techniques. The success rate will probably be much lower where staff have less experience and is a great deal lower if ordinary surgical techniques are used. Nor are these operations generally available, and you may have to travel a considerable distance to find a medical centre which is able and willing to perform them. For an operation on the NHS you may have to wait up to six months. Some doctors will offer to do it privately. The cost is likely to be around ?1,500, and it is obviously important to be sure that the doctor is experienced in the use of these techniques.
Two other surgical procedures for blocked or damaged tubes have been widely reported in the last year or so. Neither has yet had much success. Since 1974 doctors have been experimenting with fallopian tube transplants, first on animals and then on human beings. But although there have been successes with animals, the only human success has been a woman who had one of her own tubes transferred from one side of the body, where the ovary was not working, to the other, where the ovary functioned but the tube was blocked. Further advances with tubal transplants depend on developing our ability to stop the body rejecting a 'strange' tube, and until this has been done, tubal transplants do not have much of a future. Most of the experimental work is being performed in the USA.
The other surgical procedure is the use of lasers to clear blocked tubes. Laser surgery uses heat instead of a blade to cut and clear blockages. This now has some support in the USA, but is not available in this country on the NHS and has been dismissed by one leading British surgeon as a 'gimmick'. A trial at Hammersmith Hospital found that while healing was quicker using lasers, the operation took a great deal longer, was less accurate and less delicate. In particular there is a danger that laser beams may damage or destroy tissues that he below the area being operated on.
Fallopian tubes are complicated mechanisms which are responsible for wafting the egg from the ovary to the uterus and in which the fertilised egg lives for several days before it passes on down to the womb. During these days the egg undergoes important changes. The mechanisms responsible for all this are not properly understood. Tubal surgery is the first line of treatment for any woman with blocked tubes, but if it doesn't work you may have to think about treatments like in vitro fertilisation.
Surgical operations for men now have good success rates for some causes of infertility. One of the commoner causes of infertility in men is a condition known as varicocele, which is found in about thirty per cent of infertile men. A blood vessel around the scrotum becomes enlarged rather like a varicose vein. Nobody knows quite why this condition should cause infertility (normally in the form of a low sperm count), and some men remain unaffected by it even with an enlarged blood vessel. Nevertheless, experience has shown that simple surgical removal of the engorged vein quickly restores fertility in about eighty per cent of cases. A probable explanation is that the extra venous tissue brings more blood, raising the temperature and reducing the rate of sperm production (or survival) -rather like tight underpants do when they hold the testicles against the body.
It may also be possible to treat surgically men who have conditions such as undescended testicles (and who therefore cannot produce sperm), though this is usually performed in conjunction with hormone treatment which stimulates the biochemical mechanisms responsible for the maturation of the testicles. But as in most cases of infertility treatment the emphasis has been on the treatment of women.