BMI in relation to sperm count: an updated systematic review and collaborative meta-analysis

• Published in: Human Reproduction Update
• Main Authors: Sermondade, N., Faure, C., Fezeu, L., Shayeb, A. G., Bonde, J. P., Jensen, J. K., Van Wely, M., Cao, J., Martini, Ana Carolina, Eskandar, M., Chavarro, J. E., Koloszar, S., Twigt, J. M., Ramlau Hansen, C. H., Borges Jr, E., Lotti, F., Steegers Theunissen, R. P. M., Zorn, B., Polotsky, A. J., La Vignera, S., Eskenazi, B., Tremellen, K., Magnusdottir, E. V., Fejes, I., Hercberg, S., Lévy, R., Czernichow, S.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Oxford University Press
• Subjects: Obesity; BMI; Sperm concentration; Total sperm count; Meta-analysis; Andrología; Medicina Clínica; CIENCIAS MÉDICAS Y DE LA SALUD; Argentina; Bajos; Faure; Verdier; Iceland; Islandia
• Online Access: http://hdl.handle.net/11336/11779

Background: The global obesity epidemic has paralleled a decrease in semen quality. Yet, the association between obesity and sperm parameters remains controversial. The purpose of this report was to update the evidence on the association between BMI and sperm count through a systematic review with meta-analysis. Methods: A systematic review of available literature (with no language restriction) was performed to investigate the impact of BMI on sperm count. Relevant studies published until June 2012 were identified from a Pubmed and EMBASE search. We also included unpublished data (n ¼ 717 men) obtained from the Infertility Center of Bondy, France. Abstracts of relevant articles were examined and studies that could be included in this review were retrieved. Authors of relevant studies for the meta-analysis were contacted by email and asked to provide standardized data. Results: A total of 21 studies were included in the meta-analysis, resulting in a sample of 13 077 men from the general population and attending fertility clinics. Data were stratified according to the total sperm count as normozoospermia, oligozoospermia and azoospermia. Standardized weighted mean differences in sperm concentration did not differ significantly across BMI categories. There was a J-shaped relationship between BMI categories and risk of oligozoospermia or azoospermia. Compared with men of normal weight, the odds ratio (95% confidence interval) for oligozoospermia or azoospermia was 1.15 (0.93–1.43) for underweight, 1.11 (1.01–1.21) for overweight, 1.28 (1.06– 1.55) for obese and 2.04 (1.59–2.62) for morbidly obese men. Conclusions: Overweight and obesity were associated with an increased prevalence of azoospermia or oligozoospermia. The main limitation of this report is that studied populations varied, with men recruited from both the general population and infertile couples. Whether weight normalization could improve sperm parameters should be evaluated further. Fil: Sermondade, N. Hôpital Jean Verdier; Francia. Universite de Paris 13-nord; Francia Fil: Faure, C. Hôpital Jean Verdier; Francia. Universite de Paris 13-nord; Francia Fil: Fezeu, L. Universite de Paris 13-nord; Francia Fil: Shayeb, A. G. University Hospital of Wales; Reino Unido Fil: Bonde, J. P. Bispebjerg Hospital of Copenhagen University; Dinamarca Fil: Jensen, J. K. University Department of Growth and Reproduction; Dinamarca Fil: Van Wely, M. Academic Medical Centre; Países Bajos Fil: Cao, J. Third Military Medical University; China Fil: Martini, Ana Carolina. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Cordoba. Instituto de Investigaciones en Ciencias de la Salud; Argentina Fil: Eskandar, M. King Khalid University; Arabia Saudita Fil: Chavarro, J. E. Harvard University. Harvard School Of Public Health; Estados Unidos. Harvard Medical School; Estados Unidos Fil: Koloszar, S. University of Szeged; Hungría Fil: Twigt, J. M. University Medical Center; Países Bajos Fil: Ramlau Hansen, C. H. Aarhus University; Dinamarca Fil: Borges Jr, E. Fertility-Assisted Fertilization Center; Brasil Fil: Lotti, F. Universita Degli Studi Di Firenze; Italia Fil: Steegers Theunissen, R. P. M. University Medical Center; Países Bajos Fil: Zorn, B. University Medical Center Ljubljana; Eslovenia Fil: Polotsky, A. J. University of Colorado Denver; Estados Unidos Fil: La Vignera, S. University of Catania; Italia Fil: Eskenazi, B. University Of California Berkeley; Estados Unidos Fil: Tremellen, K. University of South Australia; Australia Fil: Magnusdottir, E. V. University of Iceland; Islandia Fil: Fejes, I. University of Szeged; Hungría Fil: Hercberg, S. Universite de Paris 13-nord; Francia. Hôpital Avicenne; Francia Fil: Lévy, R. Hôpital Jean Verdier; Francia. Universite de Paris 13-nord; Francia Fil: Czernichow, S. University of Versailles Saint Quentin en Yvelines; Francia. Centre for Research in Epidemiology and Population Health; Francia