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Elisabeth Carlsen

Publications and source records attributed to Elisabeth Carlsen.

10 recordsLinked to original sources
PubMed2004

Association of in utero exposure to maternal smoking with reduced semen quality and testis size in adulthood: a cross-sectional study of 1,770 young men from the general population in five European countries.

Between 1996 and 1999, the authors invited all young men from five European countries who were undergoing compulsory medical examination for possible military service to participate in a study on male reproductive health. The participation rate was 19% in two cities in Denmark (n = 889), 17% in Oslo, Norway (n = 221), 13% in Turku, Finland (n = 313), 14% in Kaunas, Lithuania (n = 157), and 19% in Tartu, Estonia (n = 190). Each man provided a semen sample, was examined by a physician, and, in collaboration with his mother, completed a questionnaire about general and reproductive health, current smoking habits, and exposure to smoking in utero. After adjustment for confounding factors, men exposed to smoking in utero had a reduction in sperm concentration of 20.1% (95% confidence interval (CI): 6.8, 33.5) and a reduction in total sperm count of 24.5% (95% CI: 9.5, 39.5) in comparison with unexposed men. Percentages of motile and morphologically normal sperm cells were 1.85 (95% CI: 0.46, 3.23) and 0.64 (95% CI: -0.02, 1.30) percentage points lower, respectively, among men exposed in utero, and exposed men had a 1.15-ml (95% CI: 0.66, 1.64) smaller testis size. The associations were present when data from the study centers were analyzed separately (though not in Lithuania, where only 1% of mothers smoked during pregnancy), although the strength of the association varied. Maternal smoking may have long-term implications for the reproductive health of the offspring. This is another good reason to advise pregnant women to avoid smoking.

Adolescent↗
PubMed2004

Effects of ejaculatory frequency and season on variations in semen quality.

OBJECTIVE: To describe the intraindividual variation in semen parameters. DESIGN: Prospective, longitudinal study. SETTING: Academic research environment. PATIENT(S): Twenty-seven healthy men, followed monthly for 16 months. INTERVENTION(S): Monthly semen samples were collected, as well as information regarding duration of abstinence, febrile episodes, and ejaculatory frequency. MAIN OUTCOME MEASURE(S): Sperm concentration, percentage immotile spermatozoa, and percentage morphologically normal spermatozoa. RESULT(S): There were no significant seasonal variations in sperm concentration, motility, or morphology. The ejaculatory frequency was significantly higher during spring compared with winter months. There was a significant difference in sperm concentration with respect to having one, two, or more than two ejaculations during a 7-day period before the abstinence period. Sperm motility and morphology were not affected by ejaculatory frequency. Duration of abstinence, ejaculatory frequency, and fever accounted only little for the high intraindividual variation in individual semen parameters. Three semen samples compared with two reduced the intraindividual variations as follows: sperm concentration from 41% to 33.5%, percentage normal spermatozoa from 6.9% to 5.7%, and percentage immotile spermatozoa from 19% to 15.5%. CONCLUSION(S): Ejaculatory frequency but not season significantly affected sperm concentration. Most of the intraindividual variations in semen parameters could not be explained by duration of abstinence, fever, or ejaculatory frequency.

Ejaculation↗
PubMed2004

Frequent polymorphism of the mitochondrial DNA polymerase gamma gene (POLG) in patients with normal spermiograms and unexplained subfertility.

BACKGROUND: Male fertility largely depends on the quality of sperm production, which may be affected by environmental and genetic factors. In this study, we explored a possible role of the polymerase gamma (POLG) gene polymorphism, recently reported to be associated with male infertility in some populations. METHODS: The polymorphic CAG repeat (usually 10 codons long) in the POLG gene was studied in 1298 male subjects: 429 patients with infertility/subfertility, and 869 controls (495 men from the general population with unknown fertility and 374 recent fathers). In all subjects, the POLG polymorphism was assessed in relation to their semen quality, and--in the fertile controls--with biological fecundity measured as waiting time-to-pregnancy (TTP) for the couples. In the patients lacking the common POLG allele, the outcome of the assisted reproductive techniques (ART) for the couples was evaluated. RESULTS: The absence of one (10/ not equal to 10) or both common POLG alleles (not equal to 10/not equal to 10) was more frequent among the subfertile patients than among fertile controls (P=0.021 and P=0.04 respectively). The estimated predictive value for infertility in a man homozygous for the POLG polymorphism was 15.5% (95% CI: 4.8-51%). There was a positive association with sperm concentration: 14.3% of the normospermic subfertile patients were homozygous for the absence of the common POLG allele (not equal to 10/not equal to 10), in comparison with 2.3% of unselected controls (P=0.001) and 0.9% of the fertile men (P=0.0001). No association with sperm motility, morphology and TTP was found. Spermatozoa of the three not equal to 10/not equal to 10 patients treated with IVF retained the ability to penetrate the egg, but the fertilization rate was low. Nine homozygous not equal to 10/ not equal to 10 patients were treated with ICSI, resulting in pregnancy in seven couples. CONCLUSIONS: The POLG gene polymorphism should be considered as a possible contributing factor in patients with unexplained subfertility and normal spermiograms. The oocyte penetration ability of sperm may be partially impaired in the not equal to 10/not equal to 10 patients but most of them can be successfully treated with ICSI.

Adult↗
PubMed2003

History of febrile illness and variation in semen quality.

BACKGROUND: The purpose of this study was to analyse the effect of a history of febrile illness on semen quality. METHODS: Twenty-seven healthy men (median age 24.4 years) were followed with monthly semen samples and a daily record of the occurrence of experienced febrile episodes over a 16 month period between March 1998 and June 1999 in Copenhagen, Denmark. Semen samples were analysed for semen volume, sperm concentration, percentage immotile sperm and percentage morphologically normal sperm. RESULTS: Sperm concentration significantly decreased by 32.6% (95% confidence interval -49.9; -9.2) following fever during meiosis and by 35.0% (-50.5; -14.6) following fever during the postmeiotic period of spermatogenesis (spermiogenesis). The percentage of morphologically normal sperm was decreased by 7.4% (-11.6; -3.0) and the percentage of immotile sperm was increased by 20.4% (6.0; 36.8) by fever during spermiogenesis. The number of days the men experienced fever significantly affected their semen parameters. Thus fever during meiosis and spermiogenesis reduced sperm concentration with respectively 7.1% (-12.9; -0.9) and 8.5% (-13.6; -3.0) per day of fever. The percentage of morphologically normal sperm decreased 1.6% (-2.5; -0.6) and the percentage of immotile sperm increased 4.5% (1.7; 7.3) per day of fever during spermiogenesis. There was, however, a large variation in the individual response to fever. CONCLUSIONS: Sperm concentration, morphology and motility in a semen sample are adversely affected by a febrile episode during the postmeiotic period of spermatogenesis (spermiogenesis). Sperm concentration was also adversely affected by fever during the period of meiosis, whereas fever at other time points during spermatogenesis did not seem to significantly affect these sperm parameters. The adverse effect seemed to be dependent upon the number of days with fever.

Adult↗
PubMed2003

Variation in levels of serum inhibin B, testosterone, estradiol, luteinizing hormone, follicle-stimulating hormone, and sex hormone-binding globulin in monthly samples from healthy men during a 17-month period: possible effects of seasons.

To obtain information on the scale of the intraindividual variation in testicular hormone, blood samples for inhibin B determination were collected monthly in 27 healthy male volunteers during a 17-month period. In addition, the traditional reproductive hormones FSH, LH, testosterone, estradiol, and SHBG were measured. The intraindividual variation in inhibin B over the study period was, on the average, 10%, corresponding to the assay variation of the inhibin B assay, indicating that most of the observed day to day variation in inhibin B levels in men could be explained by assay variation. A seasonal variation was observed in LH and testosterone levels, but not in the levels of the other hormones. The seasonal variation in testosterone levels could be explained by the variation in LH levels. The seasonal variation in LH levels seemed to be related to the mean air temperature during the month before blood sampling, but not to the length of daylight or the hours of sunshine. In conclusion, our data showed that day to day levels of inhibin B are relatively constant in men and do not seem to be influenced by seasonal factors. In contrast, we found a seasonal variation in LH and testosterone levels in men. The peak levels of both LH and testosterone were observed during June-July, with minimum levels present during winter-early spring. Air temperature, rather than light exposure, seems to be a possible climatic variable explaining the seasonal variation in LH levels.

Adult↗
PubMed2002

CAG repeat length in androgen-receptor gene and reproductive variables in fertile and infertile men.

Several reports implicated a relation between the trinucleotide (CAG) repeat length in the androgen-receptor gene and male infertility, whereas others failed to find an association. We investigated the CAG repeat length in relation to sperm production and reproductive hormones in 119 infertile men and 110 men with proven fertility. We found no difference in the distribution of CAG repeat lengths between the groups and no association with reproductive parameters. This finding suggests that, within the normal range of 14-33 repeats, there is no biological link between the CAG repeat length and fertility. This lack of association was comfirmed by an analysis of the data from all previously published European studies (in total 674 infertile men and 660 controls).

Adolescent↗
PubMed2002

Poor semen quality may contribute to recent decline in fertility rates.

During past decades, we have witnessed a remarkable decline in fertility rates (number of births per 1000 women of reproductive age) in the industrialized world. It seems beyond doubt that the enormous social changes of our societies play the major role in this decline, but can it be attributed to changing social structures alone or is a reduced fecundity in the population also a factor? To address this we have focused on trends in teenage pregnancies (which to a large extent are unplanned). During the period in question fertility rates among 15-19 year old Danish women have been falling and the decline in fertility rate is not counterbalanced by an increase in the rate of induced abortion. When seen together with recent results from Denmark, which have shown that more than 30% of 19 year old men from the general population now have sperm counts in the subfertile range, we argue that this fall may not be attributable to social factors, changes in conception practices or diminished sexual activity alone. It seems reasonable also to consider widespread poor semen quality among men as a potential contributing factor to low fertility rates among teenagers. Due to the concern caused by the low sperm count among younger Danish men, the Danish Ministries of Health and Environment have launched a surveillance programme which includes an annual examination of the semen quality in 600 young Danes from the general population. We propose that researchers in other countries with low and falling fertility rates among young women should consider the possibility that semen quality of their younger male cohorts may also have deteriorated.

Adolescent↗
PubMed2002

East-West gradient in semen quality in the Nordic-Baltic area: a study of men from the general population in Denmark, Norway, Estonia and Finland.

BACKGROUND: Denmark and Norway have a three-fold higher incidence of testicular cancer than Estonia and Finland. Groups of young men from Denmark, Norway, Finland and Estonia were investigated to elucidate whether semen parameters and other related parameters follow a gradient between these countries, as does the gradient in incidence of testicular cancer. METHODS: In total, 968 young men from the general population in these four countries were investigated according to the same protocol. Possible confounders were evaluated, and included in the statistical analysis when appropriate. Inter-laboratory differences in assessment of sperm concentrations were controlled by an external quality control programme and morphology assessment was centralized to one person. RESULTS: The Finnish and Estonian men had an adjusted median sperm concentration of 54 and 57 x 10(6)/ml, respectively and the Norwegian and Danish men 41 x 10(6)/ml. The corresponding total sperm counts were 185, 174, 133 and 144 x 10(6). The frequency of normal sperm in men from Finland was 8.9%, Estonia 9.2%, Norway 6.9% and Denmark 6.4%. Within all four groups of men, a relationship between increasing levels of inhibin-B and increasing sperm counts was observed. However, inhibin-B levels were not predictive of sperm count differences between countries. CONCLUSIONS: It is believed that the men examined were representative of the normal population of young men in all four countries as they were recruited from groups attending a compulsory medical examination, and not selected for known fertility or semen quality. Moreover, the majority of participants had no prior knowledge of their fertility potential. It appears that an east-west gradient exists in the Nordic-Baltic area with regard to semen parameters, this being in parallel with the incidences of testicular cancer. Further investigations are required to determine whether these findings are due to genetic differences, to different environments, or perhaps to a combination of both factors.

Adult↗
PubMed2002

Inhibin B: a marker for the functional state of the seminiferous epithelium in patients with azoospermia factor C microdeletions.

Testicular production of inhibin B is believed to be dependent on the presence of germ cells within the seminiferous tubules. However, this association has recently been questioned in patients with deletions of azoospermia factor (AZF) on the Y chromosome. We have addressed this problem in 442 unselected infertile/subfertile patients (excluding obstructive and iatrogenic forms) who were analyzed for Yq microdeletions. AZFc microdeletions were found in 16 patients (3.8% of the total infertile group, but 9% of the subgroup with azoospermia or severe oligozoospermia with sperm concentration <1 x 10(6)/ml). The reproductive hormone profiles in patients with AZFc microdeletions were analyzed and compared with those in infertile patients without microdeletions and those in fertile control individuals. The mean serum inhibin B concentration in the patients with AZFc microdeletions (39.5 +/- 36.0 pg/ml) was significantly lower than that in the group of infertile patients without microdeletions (134.6 +/- 88.5 pg/ml). However, no significant difference was found compared with that in a matched group of infertile patients with comparably low sperm counts (72.6 +/- 75.5 pg/ml). Bilateral testicular biopsies in the AZFc-deleted patients revealed a variable histological pattern suggestive of a progressive depletion of seminiferous epithelium. An association between testicular pathology and the reproductive hormone profile was found; the more severe forms had lower inhibin B and higher FSH levels. Importantly, if Sertoli cell-only tubules were prevalent in the biopsy, inhibin B was invariably undetectable. In patients with bilateral spermatocytic arrest, inhibin B remained within the normal range, which is consistent with a role of spermatocytes in the maintenance of inhibin B secretion. Our data support the view that, in contrast to recently published data, in patients with AZF microdeletions the serum concentration of inhibin B is dependent upon the functional interaction between Sertoli cells and spermatocytes and/or spermatids.

Adult↗