Dataset Information

Semen quality of 1559 young men from four cities in Japan: a cross-sectional population-based study.

ABSTRACT:

Objectives

To provide information of semen quality among normal young Japanese men and indicate the frequency of reduced semen quality.

Design

Cross-sectional, coordinated studies of Japanese young men included from university areas. The men had to be 18-24 years, and both the man and his mother had to be born in Japan. Background information was obtained from questionnaires. Standardised and quality-controlled semen analyses were performed, reproductive hormones analysed centrally and results adjusted for confounding factors.

Setting

Four study centres in Japan (Kawasaki, Osaka, Kanazawa and Nagasaki).

Participants

1559 men, median age 21.1 years, included during 1999-2003.

Outcome measures

Semen volume, sperm concentration, total sperm count, sperm motility, sperm morphology and reproductive hormone levels.

Results

Median sperm concentration was 59 (95% CI 52 to 68) million/ml, and 9% and 31.9% had less than 15 and 40 million/ml, respectively. Median percentage of morphologically normal spermatozoa was 9.6 (8.8 to 10.3)%. Small, but statistically significant, differences were detected for both semen and reproductive hormone variables between men from the four cities. Overall, the semen values were lower than those of a reference population of 792 fertile Japanese men.

Conclusions

Assuming that the investigated men were representative for young Japanese men, a significant proportion of the population had suboptimal semen quality with reduced fertility potential, and as a group they had lower semen quality than fertile men. However, the definitive role-if any-of low semen quality for subfertility and low fertility rates remain to be investigated.

SUBMITTER: Iwamoto T

PROVIDER: S-EPMC3641477 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Semen quality of 1559 young men from four cities in Japan: a cross-sectional population-based study.

Iwamoto Teruaki T Nozawa Shiari S Mieno Makiko Naka MN Yamakawa Katsunori K Baba Katsuyuki K Yoshiike Miki M Namiki Mikio M Koh Eitetsu E Kanaya Jiro J Okuyama Akihiko A Matsumiya Kiyomi K Tsujimura Akira A Kanetake Hiroshi H Eguchi Jiro J Skakkebaek Niels E NE Vierula Matti M Toppari Jorma J Jørgensen Niels N

BMJ open 20130429 4

<h4>Objectives</h4>To provide information of semen quality among normal young Japanese men and indicate the frequency of reduced semen quality.<h4>Design</h4>Cross-sectional, coordinated studies of Japanese young men included from university areas. The men had to be 18-24 years, and both the man and his mother had to be born in Japan. Background information was obtained from questionnaires. Standardised and quality-controlled semen analyses were performed, reproductive hormones analysed centrall ...[more]

PMID: 23633418

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Dataset Information

Semen quality of 1559 young men from four cities in Japan: a cross-sectional population-based study.

Objectives

Design

Setting

Participants

Outcome measures

Results

Conclusions

Publications

Semen quality of 1559 young men from four cities in Japan: a cross-sectional population-based study.

Similar Datasets

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