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How does semen analysis relate to actual fertility? August 2000 Welcome This is the second Case Discussion in our series designed to give you some further insights into managing cases of infertility. This case follows the path of a couple where the male partner has an abnormal sperm test. It discusses the short comings of semen analysis in predicting potential fertility. It also discusses different management options. Initial Presentation Anne has been trying to conceive for the last 15 months. She has regular periods without dysmenorrhoea and has intercourse approximately three times a week. She has had regular pap smears and is generally healthy. Neither she nor her partner Brendan have had children in previous relationships.Initial investigations are performed which show the folllowing: Anne Serum progesterone taken on day 23 of a 30 day cycle: 40 nmol/l (luteal phase level) Rubella titre - 1:40 Brendan Semen analysis: Vol 2.5 mls (RR 3-6) Viscosity normal Motility: 40% rapid progressive 5% slow progressive 55% non-motile Abnormal morphology 80% Sperm count 15 x 10 6 /ml (>20x10 6 ) Serum FSH 6 iu/l (RR 2-10) Consultant Comment Anne's cycles seem regular and ovulatory. It is important to interpret the progesterone result in relation to the timing of the next period. Peak levels of progesterone occur 5-10 days before the next period and the level should be greater than 20 nmols/l. The semen analysis is abnormal but it is not a test which gives an absolute indication of infertility - unless sperm is totally absent from the ejaculate. A number of general observations can be made The lower limit of sperm number is set at 20 x 10 6 /ml but 20% of men who have fathered children and who request vasectomy have a sperm count of 20 x 10 6 or less. When azoospermic men with gonadotropin deficiency are treated with gonadotropins, pregnancies begin to occur when sperm counts rise above 2 x 10 6 /ml. Sperm counts can vary by as much as 100% in individuals. A febrile illness may cause a temporary cessation of sperm production but since it takes 72 days for sperm to mature, the effect of this on the sperm count may not be apparent until months after the illness. A repeat semen analysis at least a month after the first is advisable, if an abnormality is found. Sperm motility is a valuable indication of the quality of healthy sperm. Loss of sperm motility may mean that sperm are immature or dead or that sperm antibodies are clumping the sperm tails together preventing movement. Abnormal morphology is another non-specific indicator of sperm quality. Sperm in normal fertile men have a variable appearance and "normal morphology" is defined very strictly. This does not mean that some sperm with abnormal morphology are not able to fertilise. Nor does it imply that such sperm carry abnormal chromosomes. The serum FSH is normal - this is often the case in men with moderate abnormalities of their semen. A level greater than 10 iu/l indicates that the Sertoli cells which nurture the developing sperm are substantially damaged, suggesting a poor prognosis. Subsequent Assessment Brendan is reviewed and a more thorough history is taken. He has had no significant past illness or injury and he takes no medications. Examination shows normal genitalia with normal sized testes. A repeat semen analysis is essentially unchanged. Consultant Comment Unfortunately, a cause of impaired spermato-genesis is rarely found. It is worth asking about delayed descent of the testes and exposure to drugs such as sulphasalazine or toxins such as heavy metals, pesticides and herbicides or occupations with exposure to excessively high temperatures. Mumps without orchitis or occurring before puberty is unlikely to cause infertility. The examination should determine that there is normal secondary sexual development and that the size and consistency of the testes is normal. The vas should be identified on both sides and a varicocele should be sought with the patient standing up and doing a vasalva manoeuvre if necessary. Examination of the prostate is not usually necessary unless there is a history compatible with urethritis or prostatitis. In the absence of a diagnosed cause, there is no empirical treatment that will improve sperm counts. Bearing in mind the large normal variability of sperm counts and the back-ground rate of fertility in men with sperm of reduced quality, it is important to refer to randomised, placebo controlled trials assessed by life-table analysis to control for increasing chance of fertility with time. There is no evidence to support the value of herbs and vitamins, anabolic steroids or testosterone, empirical clomiphene or gonadotropins, boxer shorts or stress free holidays. Maintaining a healthy lifestyle, reduction of alcohol, caffeine and smoking are recommended but are unproven with respect to fertility. Treatment of varicocele remains controversial: a recent randomised trial showed an improvement in sperm quality without an overall improvement in pregnancy rates. Subsequent Consultations Anne and Brendan were reviewed again. After 18 months of trying, with the semen analysis being the way it is and with Anne's age of 28, the chances of her becoming pregnant over the next 12 months is about 25% as opposed to the usual expectation of 70%. Several plans of action are discussed: No active treatment for 12 months. Exclude tubal occlusions with laparoscopy and dye study. This would pinpoint the semen factor as being the only identifiable abnormality. Referral for a more detailed evaluation of Brendan to ensure no diagnosable abnormality. Referral for assisted reproduction (probably IVF, possible ICSI). The expectation of successful pregnancy with this treatment is around 30% with each cycle of treatment. Conclusion Anne and Brendan decided to wait another 6 months and if no pregnancy has occured by that time, they thought they would begin evaluation for assisted reproduction. Since both IVF and ICSI do not require tubal patency, Anne decides not to proceed with laparoscopy. Table : Percentage chance of conceiving over next 12 months
From Hargreave TB, Elton RA, Brit J. Urol 1983: 55 780-784  PRINT THIS PAGE
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