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Age-specific prevalence rates of phimosis and circumcision in Taiwanese boys
Ming-Chung Ko1, Chih-Kuang Liu, Wen-Kai Lee
1Department of Surgery, Taipei City Hospital, College of Medicine, Fu-Jen Catholic University, Taipei, Taiwan.
Insights
Phimosis, or nonretractable prepuce, is common in Taiwanese newborns but significantly decreases with age. By age 13, most boys achieve full preputial separation, with circumcision rates remaining low.
Area of Science:
- Pediatrics
- Urology
- Public Health
Background:
- Phimosis, characterized by nonretractability of the prepuce, is a common condition in male newborns.
- Understanding the prevalence and natural progression of phimosis is crucial for pediatric and urological care.
Purpose of the Study:
- To determine the age-specific prevalence of phimosis and circumcision in Taiwanese boys.
- To analyze the developmental changes in preputial retractability from infancy through adolescence.
Main Methods:
- Cross-sectional evaluation of 1145 boys aged 7-13 years for preputial retractability and circumcision status.
- Examination of 59 newborn male infants to assess preputial development at birth.
Main Results:
- None of the newborn infants exhibited a completely retractable prepuce (Type 3).
- The prevalence of Type 3 prepuce increased with age, reaching 84.1% by age 13.
- Conversely, Type 1 prepuce prevalence decreased from 83.1% in newborns to 0.3% in 13-year-olds.
- Circumcision prevalence showed a slight increase from 7.2% at age 7 to 8.7% at age 13.
Conclusions:
- Nonretractability of the prepuce is highly prevalent in Taiwanese newborns.
- Preputial separation and glans exposure increase with age, particularly during adolescence.
- By age 13, unretractable prepuce is rare in this population.
Background/Purpose:
To estimate the age-specific prevalence rates of phimosis and circumcision in an urban sample of Taiwanese boys.
Methods:
A convenience sample of 1145 boys aged from 7 to 13 years was enrolled and cross-sectionally evaluated for preputial retractability and status of circumcision. Another convenience sample of 59 newborn male infants was enrolled from the infant room of a city municipal hospital. These infants were examined for preputial development at birth.
Results:
None of the newborn male infants had a completely retractable prepuce (i.e. type 3). The prevalence rate of type 3 prepuce increased with age from 71.7% (95% confidence interval [CI], 66.5-75.5%) for boys aged 7 years to 72.4% (95% CI, 67.3-77.0%) for boys aged 10 years and 84.1% (95% CI, 79.6-88.0%) for boys aged 13 years. In contrast, the prevalence rate of type 1 prepuce decreased with age from 83.1% (95% CI, 71.0-91.6%) for newborn infants to 0.3% (95% CI, 0.0001-1.8%) for boys aged 13 years. On the other hand, the prevalence of circumcision slightly increased with age from 7.2% (95% CI, 5.3-10.8%) for boys aged 7 years to 8.7% (95% CI, 6.5-13.3%) for boys aged 13 years.
Conclusion:
Nonretractability of the prepuce was very common among the Taiwanese newborns. Among the school boys, the degree of preputial separation and exposure of glans increased with age and progressed even more rapidly in adolescence. Very few boys still suffered from unretractable prepuce by the age of 13.
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