title: Semen quality and alcohol intake: a systematic review and meta-analysis.
abstract: Alcohol consumption is widespread in the Western world. Some studies have suggested a negative association between alcohol intake and semen quality although others have not confirmed this. MEDLINE and Embase were searched using 'alcohol intake' OR 'alcohol consumption' OR 'alcohol drinking' OR 'lifestyle' combined with 'semen quality' OR 'sperm quality' OR 'sperm volume' OR 'sperm concentration' OR 'sperm motility' for full-length observational articles, published in English. Reference lists of retrieved articles were searched for other pertinent studies. Main outcome measures were sperm parameters, if provided as means (standard deviation or standard error) or as medians (interquartile range). Fifteen cross-sectional studies were included, with 16,395 men enrolled. Main results showed that alcohol intake has a detrimental effect on semen volume (pooled estimate for no/low alcohol consumption 0.25 ml, 95% CI, 0.07 to 0.42) and normal morphology (1.87%, 95% CI, 0.86 to 2.88%). The difference was more marked when comparing occasional versus daily consumers, rather than never versus occasional, suggesting a moderate consumption did not adversely affect semen parameters. Hence, studies evaluating the effect of changes on semen parameters on the reproductive outcomes are needed in advance of providing recommendations regarding alcohol intake other than the advice to avoid heavy alcohol drinking.
authors.affiliation: Dipartimento di Scienze Cliniche e di Comunità, Università di Milano, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milano, Italy. Electronic address: ed.ricci@libero.it.
authors.forename: Elena
authors.initials: E
authors.lastname: Ricci
authors.affiliation: Obstetrics and Gynaecology Department, IRCCS San Raffaele Scientific Institute, Milan, Italy.
authors.forename: Suha
authors.initials: S
authors.lastname: Al Beitawi
authors.affiliation: Dipartimento di Scienze Cliniche e di Comunità, Università di Milano, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milano, Italy.
authors.forename: Sonia
authors.initials: S
authors.lastname: Cipriani
authors.affiliation: Obstetrics and Gynaecology Department, IRCCS San Raffaele Scientific Institute, Milan, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Candiani
authors.affiliation: Dipartimento di Scienze Cliniche e di Comunità, Università di Milano, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milano, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Chiaffarino
authors.affiliation: Reproductive Sciences Laboratory, Division of Genetics and Cell Biology, IRCCS Ospedale San Raffaele, Milan, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Viganò
authors.affiliation: Dipartimento di Scienze Cliniche e di Comunità, Università di Milano, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milano, Italy.
authors.forename: Stefania
authors.initials: S
authors.lastname: Noli
authors.affiliation: Dipartimento di Scienze Cliniche e di Comunità, Università di Milano, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milano, Italy.
authors.forename: Fabio
authors.initials: F
authors.lastname: Parazzini
mesh_terms: D000428:Alcohol Drinking; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007248:Infertility, Male / Q000209:etiology; D008019:Life Style; D008297:Male; D011247:Pregnancy; D011256:Pregnancy Outcome; D012307:Risk Factors; D012661:Semen / Q000187:drug effects*; D055101:Semen Analysis; D013076:Sperm Count; D013081:Sperm Motility; D013094:Spermatozoa / Q000187:drug effects
keywords: alcohol consumption; lifestyle; meta-analysis; risk factors; semen quality; sperm parameters