Offspring sex ratio of Iranian dentists
Hadi Ghasemi1, Seyedeh Reihaneh Mirdehghan2, Mahshid Namdari2
1Department of Community Oral Health, School of Dentistry, Shahid Beheshti University of Medical Sciences, Daneshjou Blvd., Evin, Postal Code: 1983963113, Tehran, Iran. ha.ghasemi@sbmu.ac.ir.
Objective:
To assess the impact of occupational factors on the sex ratio of dentists' children.
Methods:
A randomly selected 501 Iranian dentists participated in a telephone interview. The participants were contacted by their mobile number to answer questions about demographic variables (gender, age, marriage status), practice-related variables (year of graduation as general or specialist dentist, years of clinical work, working hours, average number of radiographs taken in a day, and spouse's job), and questions about their children (number, gender and date of birth of each child). Kruskal-Wallis and Chi-square tests served for statistical evaluation.
Results:
Of all participating dentists, 71 % were men, about two-thirds were 35- to 50-year olds, and 89 % were married. In total, the dentists had 768 children; about 21 % had no child. Of all the children, 54 % were boys (overall sex ratio = 1.17). The offspring sex ratio was 1.13 among male dentists, 1.50 for female dentists, and 1.44 when both parents were dentists. Higher percentages of boys were prevalent among female dentists, younger dentists, and general dental practitioners (p < 0.008).
Conclusion:
Demographic and practice-related factors showed some impact on proportions of both sexes of dentists' children in this study. However, the result needs evaluation in further studies.
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