Recategorisation of body mass index to achieve andrological predictive power: a study in more than 20 000 patients

RAMÍREZ N; MOLINA RI; TISSERA A; LUQUE EM; TORRES PJ; BIANCONI S; BELTRAMONE, F; SAD-LARCHER, J; ESTOFÁN, G; MANGEAUD A; MARTINI AC

REPRODUCTION FERTILITY AND DEVELOPMENT

CSIRO PUBLISHING

Lugar: Collingwood; Año: 2020 vol. 32 p. 648 - 656

1031-3613

The aim of this study was to recategorize body mass index (BMI) in order to classify patients by their risk of suffering semen abnormalities. Patients (n=20563) assisted to an andrology laboratory and were classified in groups: underweight (BMI40). Semen quality was evaluated, determining: a) differences between groups (Anova); b) chances of suffering semen abnormalities (generalized linear models, Chi-square and Odds-ratios); c) reference values in BMI with andrological predictive power (multivariate conglomerate analyses and Manova) and d) expected values of abnormalities for each new group resulted from BMI recategorization. Morbidly obese and underweight patients showed the highest decrease in semen quality and higher chances of suffering semen abnormalities. The smallest summatory in sperm abnormalities were found at BMI=27kg/m2. Four reference values were identified, recategorizing BMI in groups according to their risk of suffering semen abnormalities. From lowest to highest: group1=BMI between 20 and 32kg/m2; group2=BMI32 to 37kg/m2; group3=BMI>37 to 42kg/m2 and group4=BMI>42kg/m2. A BMI below 20 or above 32kg/m2 is negatively associated with semen quality; these alterations increase from BMI>37kg/m2 and even further, from BMI>42kg/m2. The BMI recategorization carried out in this study has andrological predictive power.