Skip to main content

Table 1 Main characteristics of studies on caffeine intake and male fertility

From: Coffee and caffeine intake and male infertility: a systematic review

First author, year Country Number Design Setting Outcome measure Age (range or mean)
Full text
 Cole, 2006 [34] Canada 41 Retrospective cohort Obstetrics Department: planned pregnancies Fecundability 22-45
 Curtis, 1997 [27] USA 2607 Retrospective cohort Couples from farms in Ontario: planned pregnancies Fecundability 17- > 30
 Figà-Talamanca, 1996 [26] Italy 72 Cross-sectional Taxi drivers Semen variables 43.2
 Florack, 1994 [25] The Netherlands 259 Prospective cohort Non medical hospital workers’ partners Fecundability Not reported
 Horak, 2003 [32] Poland 179 Cross-sectional Fertility clinic: healthy donors and men from infertile couples Bulky DNA adducts in human sperm cells as a measure of DNA lesions 35.2
 Jensen, 1998 [30] Denmark 450 Prospective cohort Trade union members Fecundability Not reported
 Jensen, 2010 [38] Denmark 2554 Cross-sectional Young healthy men Semen variables 18-22
 Jurewicz, 2014 [40] Poland 212 Cross-sectional Healty men Sperm aneuploidy 22-45
 Klonoff-Cohen, 2002 [31] USA 221 Prospective cohort Fertility Clinic: infertile couples undergoing ART Semen variables, clinical pregnancy, live birth 38.4
 Kobeissi, 2007 [36] USA 120/100 Case-control Fertility Clinic: infertile couples Cases suffered from impaired sperm count and function; controls were the fertile husbands of infertile women 38.6 cases/39.3 controls
 Marshburn, 1989 [22] USA 446 Cross-sectional Infertile men Semen variables Not reported
 Oldereid, 1992 [23] Norway 252 Cross-sectional Men attending a fertility laboratory Semen variables Not reported
 Parazzini, 1993 [24] Italy 97/105/120 Case-control Fertility clinic Cases of dyspermia; controls: 1. normospermic men of infertile couples; 2. Fertile men of unknown semen quality Not reported
 Radwan, 2016 [42] Poland 286 Cross-sectional Healthy men DNA Fragmentation Index 22.7-44.8
 Ramlau-Hansen, 2008 [37] Denmark 344 Cross-sectional Young men, sons of mothers in Healthy Habits for Two cohort Semen variables 18-21
 Robbins, 1997 [29] USA 45 Cross-sectional Young healthy men Sperm aneuploidy 19-35
 Schmid, 2007 [35] USA 80 Cross-sectional Non smoker healthy men DNA damage 46.4
 Sobreiro, 2005 [33] Brazil 500 Cross-sectional Candidates to vasectomy Semen variables 35
 Vine, 1997 [28] USA 88 Cross-sectional Healthy males Sperm nuclear morphometric parameters 18-35
 Wesselink, 2016 [43] USA 2135 Prospective cohort Couples planning a pregnancy Fecundability 31.8
 Wogatzky, 2012 [39] Austria 1683 Cross-sectional Fertility clinic: infertile couples Semen variables 40.4
 Yang, 2015 [41] China 796 Cross-sectional Young men Semen variables 20 (median)
Published or only accessible as abstract
 Adelusi, 1998 [44] Saudi Arabia 68/28 Case-control Fertility Clinic: infertile couples Sperm motility Not reported
 Al-Inany, 2001 [45] Egypt 200 Cross-sectional Fertility Clinic: infertile couples Semen variables 23-45
 Belloc, 2013 [46] France 4474 Cross-sectional Fertility Clinic: infertile couples Semen variables, DNA fragmentation and chromatin decondensation Not reported
 Karmon, 2013 [47] USA 166 Cross-sectional Fertility Clinic: infertile couples Semen variables 36.6
 Karmon, 2014 [48] USA 105 Prospective cohort Fertility Clinic: infertile couples Clinical pregnancy rate 37
 Pecoraro, 2015 [49] Italy 1134 Cross-sectional Fertility clinic: infertile couples Fertility 33.4 fertile/38.3 infertile