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Background: Several studies have suggested a population-wide decline in the quality of semen over the past 50 years, but clear evidence for decreasing semen quality in recent decades is lacking., Methods: From 1973 through 1992 we measured the volume of seminal fluid, the sperm concentration, and the percentages of motile and morphologically normal spermatozoa in 1351 healthy fertile men. The data on the semen samples were collected at one sperm bank in Paris. The data in each calendar year were analyzed as a function of the year of donation, the age of each patient, the year of birth, and the duration of sexual abstinence before semen collection., Results: There was no change in semen volume during the study period. The mean concentration of sperm decreased by 2.1 percent per year, from 89 x 10(6) per milliliter in 1973 to 60 x 10(6) per milliliter in 1992 (P < 0.001). During the same period the percentages of motile and normal spermatozoa decreased by 0.6 percent and 0.5 percent per year, respectively (both P < 0.001). After adjustment in multiple regression analyses for age and the duration of sexual abstinence, each successive calendar year of birth accounted for 2.6 percent of the yearly decline in the sperm concentration and for 0.3 percent and 0.7 percent, respectively, of the yearly declines in the percentages of motile and normal spermatozoa (all P < 0.001)., Conclusions: During the past 20 years, there has been a decline in the concentration and motility of sperm and in the percentage of morphologically normal spermatozoa in fertile men that is independent of the age of the men.

In recent years, chemotherapy and radiations for cancer patients has become increasingly successful, and sustained remissions have been achieved. However, in young men, most of the current therapies still presently induce temporary or permanent sterility without any means of prediction. The present paper largely based on data accumulated over two decades at CECOS Paris-Bicêtre reassess the clinical role of semen cryopreservation from young men with cancer before chemotherapy and/or radiotherapy. Recent use of assisted reproduction technologies with pretherapy cryopreserved specimens (including semen of poor quality) has provided a growing number of pregnancies. These new data strongly reaffirm that semen cryopreservation should be offered to all men diagnosed with cancer since it presently provides the only reasonable chance of establishing a pregnancy after therapy.

From a collaborative study of the French "Federation des CECOS" who collected the follow up of 11,535 pregnancies, the effect of parental age on the offspring is studied. A significant influence of the donor's age is demonstrated for the occurrence of trisomy 21 (37.4 +/- 7.8 vs 34.5 +/- 6.0; p < 0.05).

The relationship between age and semen characteristics has been studied; any effect due to the influence of the length of abstinence preceding ejaculation was eliminated. There is an improvement in semen characteristics up to 25 years of age, followed by a leveling off and a subsequent decrease. This variation is not significant as far as the sperm count, semen volume, and the total number of spermatozoa are concerned. The variation, although small, is highly significant for the morphologic characteristics and prefreeze and postthaw motility. The values for the older subjects were significantly lower for postthaw motility in the group 36 to 40 years of age, in the group 41 to 45 years of age for morphologic normality, and in the group 46 to 50 years of age for prefreeze motility. The lower values in the group 21 to 25 years of age are particularly noticeable with regard to morphologic characteristics. The same curve is encountered in the variation with age of each abnormal form, but the most marked variation is found in the increased percentage of coiled tails, which first appears in the group 36 to 40 years of age.

Among the men who volunteered to become semen donors for artificial insemination at the sperm bank of Centre d'Etude et de Conservation du Sperme Humain, Paris-Bicêtre, some were brothers of the infertile men of couples entering the Artificial Insemination with Donor program. Their sperm characteristics, compared with those of other donor candidates, are clearly lower. The difference is significant for count (78.0 versus 102.8, P less than 0.05) and very significant for the percentage of motile spermatozoa (61.5 versus 66.9, P less than 0.01) and for the percentage of normal forms (51.8 versus 62.7, P less than 0.00001). The differences are even more pronounced when the brothers of azoospermic men are considered. The possibility that some cases of infertility could have a genetic origin is discussed.

Sperm examinations and/or measurements of plasma FSH, LH and testosterone were performed on 54 patients with Hodgkin's disease before and/or after 3 or 6 courses of multiagent chemotherapy (MOPP). In 24 patients without constitutional symptoms the results of fresh and frozen sperm examination were similar to those of a fertile control population. In 23 patients, pretreatment hormone levels were identical with those of controls. During the first year following completion of chemotherapy all patients had azoospermia and high FSH levels. From the second year onwards, 2 out of 16 patients had normal spermatogenesis (the wife of one of these gave birth to a healthy child), while 4 had grossly deficient spermatogenesis and 10 azoospermia. All male patients suffering from Hodgkin's disease should be asked to give sperm for freezing before chemotherapy and should be informed that spermatogenesis may be resumed from the second posttreatment year.

Between subject and within subject variances and correlations for different semen characteristics have been determined for a population of 315 fertile men who provided one or more ejaculates within an abstinence period of 1 to 5 days. The semen characteristics measured were sperm count, semen volume, pre-freeze motility and post-thaw motility. An approach via a decomposition of the variance or via a decomposition of correlation leads essentially to the same conclusions i.e. the within subject factors are not negligible but are less important than the between subject ones. Thus there is broad evidence for overall differences in the quality of the ejaculate from one subject to the other but not for different ejaculates of the same subject.

For the 13 abnormalities under consideration, the mean percentages were found to be the following: irregular head (15.2), microcephalic (9.8), elongated head (5.9), coiled tail (5.8), bent tail (4.7), thin head (4.6), cytoplasmic remains (3.2), macrocephalic (1.6), short tail (1.1), no tail (0.6), duplicate tail (0.5), duplicate head (0.4), lysis (0.4). In so far as the group studied is representative, the results obtained may be considered as "norms" with the 90th percentiles showing the upper limit of the "normal". The same mean percentages were found by MacLeod and Gold (1951) for the five abnormalities they had identified. The length of abstinence preceding the collection of the ejaculate was found to have no influence on the percentage of abnormal forms.

The experience of a sperm bank during a five year period is reported. Artificial insemination by donor (AID) was carried out on 1188 women using frozen sperm prepared in doses of 0.25 ml. A single insemination was called for during each of the first two cycles. The patients were classified in 4 categories: lost to follow-up, successes, dropouts and open cases. The success rate per cycle was about 10 per cent and was very stable for each of the first 12 cycles. The cumulative success rate was calculated by the life table technique adapted for AID analysis. A theoretical success rate (without dropouts) and an effective success rate (with dropouts) were calculated. These two rates were 68 and 55 per cent respectively after 12 cycles. The median delay to conception was 7 and 9 cycles, respectively, under theoretical and effective conditions. The spontaneous abortion rate (17 per cent) and sex-ratio (106 males for 100 females) resemble those for natural reproduction but the success rat per cycle was markedly lower even after adjusting for age.

830 couples who had asked for Artificial Insemination by Donor (AID) were questioned using separate questionnaires for the husband and for the wife. The questions were directed to the reactions that followed in succession to discovery of the sterility, the psychological conditions that led to choosing AID, their attitude as far as secrecy was concerned and finally their contribution to finding donors of sperm. Overall the husband-wife replies corresponded to one another. Frequently the reaction to the news that the man is sterile is a depressive one and to a lesser degree followed by troubles in sexual performance. The choice of AID is usually a decision of both members of the couple. Most couples express themselves as hesitant about adoption. Most of them said that secrecy about the procedure was an essential condition. It appears that, above all, male sterility had to be hidden from the circle in which they associated and from the child. It is this position as far as secrecy is concerned that makes it difficult for the couples to help in recruiting sperm donors.

The aim of this study based on the investigation of 570 semen specimens providing from 251 patients is to determine the correlation existing between initial sperm quality and its ability to bear cryo-preservation. Semen quality was estimated according to the usual parameters : numeration, motility and morphology of spermatozoa. Motility recovery on the one hand, and fertilizing capacity after cryo-preservation on the other hand, allowed an estimation of the sperm ability to bear thawing. Motility recovery seems to depend widely on the initial sperm quality. The persistence of sperm fertilizing capacity partly depends on the motility recovery and consequently partly on the initial quality. However, some semen specimens seem to lose their fertilizing capacity in spite of a good motility after deep-freezing.