ABSTRACT
Infertility can be a major concern for couples trying to conceive, and occupational hazards may constitute a main cause of infertility in men. Studies conducted throughout the world indicate that physical and chemical hazards in the workplace can have a negative impact on male fertility. The main objective of this study was to determine the frequency of occupational categories of men who attended an infertility clinic, and to evaluate the differences in the semen quality parameters among occupational categories. This cross-sectional study was conducted on 1164 males who were referred to the Infertility Research Center in Tehran for treatment of infertility in order to evaluate the effects of certain occupations on infertility. The participants were divided into several categories according to their occupations and evaluated by means of a questionnaire for duration of infertility, BMI, sperm count, percentage of normal sperm morphology and percentages of sperm with class A and class B motilities. Descriptive statistics, analysis of variance, and correlations were conducted using SPSS 16.0 for Windows. There were no statistically significant differences in the mean sperm count or sperm morphology between occupational categories. Assessment of the differences in the frequency of sperm motility classes between occupational categories revealed a significant difference only in the frequency of sperm with class B motility. The lowest mean percentages of sperm with class B motility were seen in those involved in the transportation industry, a finding in agreement with a number of other researches. Our findings revealed an association between occupation and sperm motility. Since our study population was relatively small and in many cases exposures to work hazards were brief, a larger study group must be evaluated in order to support the preliminary results of this study
ABSTRACT
Artificial stimulation of mouse oocyte, in the absence of sperm contribution, can induce its parthenogenic activation of oocyte. Ultrasound is one of the newest methods for artificial activation of mammal oocytes, and its successful utilization in pig oocyte activation has been recently reported. Our objective was to assess the effect of ultrasound on mouse oocyte activation. Our groups included1 control group, 3 experimental groups consisting of 1, 2 and 3 repetitions of ultrasound exposure, and 3 sham groups handled similar to experimental groups but ultrasound system was off during treatments. In experimental groups, adult female NMRI mice at the interval between pregnant mare serum gonadotropin [PMSG] and human corionic gonadotropin [hCG] injections, were exposed to continuous ultrasound with 3.28 MHz frequency and peak intensity [I pk]=355 mW/cm2. Sixteen hours after injection of hCG, the mice were euthanized and their oocytes were collected; thereafter, parthenogenic oocytes were counted. Data analysis using the ANOVA test shows a significant increase in the number of parthenogenic oocytes in mice with 3 overall exposures to ovarian ultrasound [p<0.05]. A significant decrease in the number of metaphase II [MII] oocytes numbers was also seen in mice treated with ultrasound [p<0.05]. Ultrasound is thought to induce pores generation in oocyte membranes and provides an easier inward transport of Ca++ into oocytes. This phenomenon can induce meiosis resumption in immature oocytes. With increased exposure repetitions from 1 to 3 times and greater Ca++ arrival, oocytes can be parthenogenetically activated