Page modified at: 31/08/2010
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30-40% Tubal blockage or endometriosis
10-15% Ovulation problems
to see a Youtube Video on Ovulation
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30-40% Male (sperm) problems
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In almost half the cases of subfertility, there is a male contribution to the problem.
The initial investigation requires a sample of semen for analysis.
This is usually produced at home after abstaining from ejaculation for 2-3 days. A shorter time than this will reduce the total number and longer abstinence can lead to a falsely high number of poorly motile (slow swimming) sperms. The sample needs to be delivered to the laboratory within one hour for analysis. The following are considered a normal result:
Concentration: more than 20 million per ml
Motility: more than 50% progressively motile
Form: more than 30% normal appearance
White blood cells: less than 1 million per ml
Most clinics suggest two samples be received for analysis, particularly if there are any abnormalities with the first test. It takes around 74 days to make sperm, so if 2 samples are checked in a shorter time than this, it is likely that they are from the same population. This might be important if, for example, a man had a viral infection, or a poor result followed a period of particularly heavy alcohol intake. In this case, it would be better to delay the second sample for 3 months.
There are several other specialised tests for semen analysis, but these are not routinely recommended, as their ability to predict infertility and direct the correct treatment has not been proven. One particular test is the anti-sperm antibody test. Antibodies normally fight infections, but sometimes a man produces antibodies that bind to his own sperm, either reducing the motility or interfering with fertilisation of the egg. Many studies have looked at the exact implications for this and it now seems that only heavy antibody binding seen on the semen analysis, when associated with the problems mentioned above, are likely to be significant. In any case, there is no proven treatment apart from intracytoplasmic sperm injection (ICSI).
Almost 90% of male problems are not amenable to treatment to improve the sperm count, and will require some form of assisted conception if pregnancy does not occur naturally.
CAUSES OF MALE INFERTILITY
Idiopathic abnormal sperm count
’Idiopathic’ refers to the fact that no cause for the problem is found. This happens about 75% of the time when there is a male contribution to the infertility. Even with moderate problems such as low counts less than 5 million/ml or poor motility, it is still possible to conceive normally. When there is no sperm (azoospermia) then clearly it is unlikely.
An absence or blockage in the tube from the testes to the urethra (the vas deferens) is an uncommon cause of male infertility. It may be discovered on a scan if there are no sperms found at all, but it is treatable by surgery.
A varicocele is a swelling of the veins around the testes and for some time this was thought to be a significant cause of infertility, but it is now clear that this is less likely. As only one in 15-20 men who have surgery would be likely to benefit, it is important to consider the risks of an operation.
Gene problems are unusual, but are more common in men who have very few or no sperms (about 10%). Whilst most gene abnormalities are not overtly apparent, there is concern that one particular type which is associated with infertility (Y-chromosome deletions) may be passed on to male offspring when assisted techniques such as ICSI do result in pregnancy.
Once again, a hormone disorder is an unusual cause of male infertility. This is sometimes treatable if the signal from the brain is the problem (gonadotrophin deficiency), but if the testes have stopped working altogether, as happens in around 13% of male infertility, success is unlikely.
Men who smoke have a 13-17% lower sperm count that those who do not. High alcohol intake can markedly reduce the sperm count and motility, however low and moderate consumption up to normal recommended levels has not been found to lead to problems.
Tight fitting clothes and prolonged periods of sitting can lead to a reduction in sperm count, through excessive heating of the testes. Men who have an abnormal semen analysis should wear loose fitting trousers and underwear such as boxer shorts.
Cannabis, cocaine and anabolic steroids all reduce the sperm count and affect motility and number of normal sperms.
CAUSES OF FEMALE INFERTILITY
Blockage of the fallopian tubes can be suggested on a hysterosalpingogram (HSG), but it is important to do a laparoscopy to confirm whether this is the case or not. Sometimes inadequate pressure when inserting the dye during a HSG can lead to a suggestion of blockage when one doesnt exist. Laparoscopy also gives the opportunity of taking a close look at the tubes to decide on the usefulness of tubal surgery to open them.
The most common cause of blocked tubes is infection, and the most common infection implicated is called chlamydia. About 70% of women who have blocked tubes have had a chlamydia infection, though half the time it will have been silent and they will not have even been aware of it.
Where the tubes look otherwise quite normal and the block is close to the uterus, or where scar tissue adhesions are causing a distinct blockage, it is possible to do tubal surgery to open them up. Adhesions can sometimes be broken down through the laparoscopic adhesiolysis. Other times or where a small segment of blocked tube needs to be removed, an open operation is needed. The tube may be swollen and full of fluid (hydrosalpinx) or the damage may be more severe and close to the finger-like fimbrial end of the tube where the egg first enters. In these situations tubal surgery is much more unlikely to be successful and in-vitro fertilisation (IVF) will often be suggested in the first instance. In any case if pregnancy hasnt happened within 12 months following tubal surgery, IVF should be considered as the chance of success after this time is much lower.
Reversal of sterilisation is successful about 50-70% of the time, but is only rarely available on the NHS.
It is ovulation and the hormone changes that subsequently follow which leads to the normal menstrual cycle. Thus, irregular periods strongly suggest that an egg is not being released each month.
Sometimes women still cycle but ovulation does not happen every month. The test for ovulation is the day 21 progesterone (for a 28 day cycle), and the term anovulation means that ovulation is not taking place. Sometimes women don't ovulate because of an overactive pituitary gland, leading to high levels of the hormone prolactin. Bromocriptine is a drug that is used to suppress this excess and it also leads to the return of ovulation in most cases. Where the ovary has exhausted its egg supply and premature ovarian failure is the diagnosis, donor eggs with IVF is the only treatment.
Polycystic ovary syndrome (PCOS) is another cause of anovulation.
Hormonal problems are sometimes found and on scan the ovary has lots of small cysts around the edge.
These are not harmful in themselves, just a sign that eggs have started to develop, but never got released.
Endometriosis is a condition where spots of the lining of the uterus (endometrium) are found inside the pelvis on the ovaries, the back of the uterus and the ligament supports of the uterus. Although extensive endometriosis involving the tubes and distorting the ovary are clearly likely to interfere with egg transport and ovulation, it is less clear how mild to moderate endometriosis exerts an effect on fertility.
The aim of treatment is to remove all the endometriosis by either cutting it out or burning it away with diathermy or laser, break down any associated adhesions and leave as much normal ovary tissue as possible. Mild to moderate endometriosis can usually be managed laparoscopically, but more severe cases require open surgery. Drug treatment may be useful after surgery, but as a primary treatment for infertility, it only delays pregnancy further.
In around 15-20% of cases no obvious cause is found, and the diagnosis of unexplained infertility is made.
Apart from being terribly frustrating, unexplained infertility means that treatment is not directed at any known cause. Approximately 60% of couples with unexplained infertility of less than 3 years duration will fall pregnant in the next 3 years without any treatment at all. Recent analysis of all the studies of clomiphene has not found it to be beneficial.
One useful treatment option is ovarian stimulation combined with a direct insemination of prepared and optimised sperms from the partner. This involves the usual monitoring of ovarian stimulation and insemination around the time of ovulation, which is achieved by passing a speculum, as during a smear test, and injecting the sample into the uterus. Pregnancy rates are typically 15% per cycle. If this is unsuccessful after 6 cycles then IVF is usually advised.