Association of obesity and occupational factors with infertility in Pakistani men seeking treatment at an infertility centre in Karachi_Pakistan : a case control study
Date of Award
Master of Science in Epidemiology & Biostatistics (MSc Epidemiology & Biostats)
Community Health Sciences
Male infertility has a wide range of causes ranging from genetic, environmental, biological, behavioral to lifestyle risk factors. In Pakistan the burden of infertility is 21% of which 35% is contributed by the male factor. Studies have shown the association of modifiable risk factors with male infertility but this information is lacking from Pakistani context. Objective: The objective of the study was to determine the association of obesity and occupational factors with infertility in Pakistani men seeking treatment at an infertility centre in Karachi-Pakistan. Methods: We conducted a case control study enrolling 201 infertile men (cases) and 200 fertile men (controls) from January to March 2013 from Australian Concept Infertility Medical Centre (ACIMC). Participants were Pakistani married men seeking infertility treatment at the study centre (ACIMC). Cases were men with impairment of any one of the normal semen parameter, while controls were men with normal semen parameters. A structured questionnaire &bodily measurement tools (such as height scale, weight scale, measuring tape and 'bioelectrical impedance analyser) were administered to collect the history of exposure to potential risk factors of male infertility among patients, after they consented to participate in the study. Results: The mean age of infertile men was 33.34 years (SD 6.04) and of fertile men was 33.74 years (SD 7.07). Infertile men had a higher mean BMI, were socioeconomically better-off as compared to fertile men with monthly income of >25000PKR (48.6% vs 32.0%), had a higher educational status of intermediate or above as compared to the fertile men (55.7% vs 35.5%) and had previous medical conditions increasing the risk of infertility as compared to the fertile men (20% vs 8.5%). The final logistic regression model included BMI, occupational exposure, educational status and previous conditions that could account for infertility. After adjusting for the effect of other covariates in the model we concluded that with every 1 kg/m2 increase in BMI the odds of being infertile was 6% higher as compared to being fertile (aOR=1.06; 95% CI=1.01, 1.11). Moreover infertile men had higher odds of being exposed to high risk occupations for >2 hours/day as compared to fertile men (a0R=1.05; 95% CI=0.69, 1.59). Conclusion & recommendations: This study indicates that obesity is associated with male infertility. Obesity is an emerging public health problem in Pakistan affecting both males and females. It not only increases the risk of hypertension, cardiac disorders, diabetes and other chronic disorders, but contributes to causing infertility in men. Moreover our findings also indicated that, higher educational status and previous medical conditions were also associated with male infertility. Thus, males with previous medical conditions should be made aware of being extra cautious for monitoring their body weight, not sitting for prolonged hours at a stretch and wearing loose clothing. These recommendations are beneficial for all men in general. The awareness can be raised through treating physicians, and public health messages. Hence, we may conclude that modifiable risk factors play an essential role in the disturbance of the semen parameters.
Zahid, N. (2013). Association of obesity and occupational factors with infertility in Pakistani men seeking treatment at an infertility centre in Karachi_Pakistan : a case control study (Unpublished doctoral thesis). Aga Khan University, Karachi, Pakistan.