title: Body mass index and human sperm quality: neither one extreme nor the other.
abstract: The aim of the present study was to investigate the still contentious association between body mass index (BMI) and seminal quality. To this end, 4860 male patients (aged 18-65 years; non-smokers and non-drinkers), were classified according to BMI as either underweight (UW; BMI <20kgm-2; n=45), normal weight (NW; BMI 20-24.9kgm-2; n=1330), overweight (OW; BMI 25-29.9kgm-2; n=2493), obese (OB; BMI 30-39.9kgm-2; n=926) or morbidly obese (MOB; BMI ≥40kgm-2; n=57). Conventional semen parameters and seminal concentrations of fructose, citric acid and neutral α-glucosidase (NAG) were evaluated. The four parameters that reflect epididymal maturation were significantly lower in the UW and MOB groups compared with NW, OW and OB groups: sperm concentration, total sperm count (103.3±11.4 and 121.5±20.6 and vs 157.9±3.6, 152.4±2.7 or 142.1±4.3 spermatozoa ejaculate-1respectively, P<0.05), motility (41.8±2.5 and 42.6±2.6 vs 47.8±0.5, 48.0±0.4 or 46.3±0.6 % of motile spermatozoa respectively, P<0.05) and NAG (45.2±6.6 and 60.1±7.9 vs 71.5±1.9, 64.7±1.3 or 63.1±2.1 mU ejaculate-1 respectively, P<0.05). Moreover, the percentage of morphologically normal spermatozoa was decreased in the MOB group compared with the UW, NW, OW and OB groups (4.8±0.6% vs 6.0±0.8%, 6.9±0.1%, 6.8±0.1 and 6.4±0.2%, respectively; P<0.05). In addition, men in the MOB group had an increased risk (2.3- to 4.9-fold greater) of suffering oligospermia and teratospermia (P<0.05). Both morbid obesity and being underweight have a negative effect on sperm quality, particularly epididymal maturation. These results show the importance of an adequate or normal bodyweight as the natural best option for fertility, with both extremes of the BMI scale as negative prognostic factors.
authors.affiliation: Cátedra de Fisiología Humana, Instituto de Investigaciones en Ciencias de la Salud (INICSA), CONICET and Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Santa Rosa 1085, X5000ESU Córdoba, Argentina.
authors.forename: E M
authors.initials: EM
authors.lastname: Luque
authors.affiliation: Laboratorio de Andrología y Reproducción (LAR), Chacabuco 1089, X5000IIK Córdoba, Argentina.
authors.forename: A
authors.initials: A
authors.lastname: Tissera
authors.affiliation: Laboratorio de Andrología y Reproducción (LAR), Chacabuco 1089, X5000IIK Córdoba, Argentina.
authors.forename: M P
authors.initials: MP
authors.lastname: Gaggino
authors.affiliation: Laboratorio de Andrología y Reproducción (LAR), Chacabuco 1089, X5000IIK Córdoba, Argentina.
authors.forename: R I
authors.initials: RI
authors.lastname: Molina
authors.affiliation: Cátedra de Estadística y Biometría, Facultad de Ciencias Exactas, Físicas y Naturales, Universidad Nacional de Córdoba, Vélez Sarsfield 299, 5000 Córdoba, Argentina.
authors.forename: A
authors.initials: A
authors.lastname: Mangeaud
authors.affiliation: Cátedra de Fisiología Humana, Instituto de Investigaciones en Ciencias de la Salud (INICSA), CONICET and Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Santa Rosa 1085, X5000ESU Córdoba, Argentina.
authors.forename: L M
authors.initials: LM
authors.lastname: Vincenti
authors.affiliation: Centro Integral de Ginecología, Obstetricia y Reproducción (CIGOR), Chacabuco 1123, X5000IIL Córdoba, Argentina.
authors.forename: F
authors.initials: F
authors.lastname: Beltramone
authors.affiliation: Centro Integral de Ginecología, Obstetricia y Reproducción (CIGOR), Chacabuco 1123, X5000IIL Córdoba, Argentina.
authors.forename: J Sad
authors.initials: JS
authors.lastname: Larcher
authors.affiliation: Centro Integral de Ginecología, Obstetricia y Reproducción (CIGOR), Chacabuco 1123, X5000IIL Córdoba, Argentina.
authors.forename: D
authors.initials: D
authors.lastname: Estofán
authors.affiliation: Cátedra de Fisiología Humana, Instituto de Investigaciones en Ciencias de la Salud (INICSA), CONICET and Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Santa Rosa 1085, X5000ESU Córdoba, Argentina.
authors.forename: M
authors.initials: M
authors.lastname: Fiol de Cuneo
authors.affiliation: Cátedra de Fisiología Humana, Instituto de Investigaciones en Ciencias de la Salud (INICSA), CONICET and Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Santa Rosa 1085, X5000ESU Córdoba, Argentina.
authors.forename: A C
authors.initials: AC
authors.lastname: Martini
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015992:Body Mass Index; D005298:Fertility / Q000502:physiology*; D006801:Humans; D007248:Infertility, Male / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D009767:Obesity, Morbid / Q000503:physiopathology*; D055101:Semen Analysis; D013076:Sperm Count; D013081:Sperm Motility / Q000502:physiology; D013094:Spermatozoa / Q000502:physiology*; D013851:Thinness / Q000503:physiopathology*; D055815:Young Adult