One in 50 teenagers still wet the bed and almost half of 19 year-olds who have a problem are wetting the bed every night, according to research published in the May issue of the UK-based urology journal BJUI International.
Professor Chung K Yeung from the Chinese University of Hong Kong teamed up with colleagues from the Prince of Wales Hospital to analyse the results of more than 16,500 questionnaires surveying children aged from five to 19.
He hopes that his findings will reassure parents of children with mild bed wetting problems, but stress the importance of seeking advice in severe cases, which can often be caused by underlying medical problems and continue into adulthood.
512 children - just over three per cent of those surveyed -reported night-time bedwetting and one in five of those also had daytime incontinence. 302 were boys and 210 were girls.
The researchers found that although bed wetting was less common as children got older, the percentage reporting severe problems increased with age.
Children and adolescents who wet the bed at night also showed a similar pattern when it came to daytime incontinence, with a higher percentage of problems reported in older age groups.
When the researchers looked in detail at the 512 children with bed wetting problems they found that:
- Mild bed wetting was much worse among younger children, with 58 per cent of five to ten year-olds and 18 per cent of 11-19 year-olds wetting the bed less than three times a week.
- But older children reported a higher level of severe problems, with 82 per cent of 11-19 year-olds wetting the bed more than three times a week, compared with 42 per cent of five to ten year-olds.
- Just over 16 per cent of five year-olds wet the bed, with boys (21 per cent) having almost twice as many problems as girls (11 per cent).
- By the age of 19, three per cent of boys and two per cent of girls were still wetting the bed.
- Just under a third of 11-19 year-old boys (32 per cent) also experienced daytime incontinence, almost double the 15 per cent recorded in the under ten age group.
- The figures for girls were lower but showed a similar trend, at 25.5 per cent for 11-19 year-olds and 12 per cent for girls under ten.
- Overall, 29 per cent of children aged 11-19 experienced daytime incontinence, compared with 14 cent of under tens.
"Bed wetting showed a general reduction as children got older" says Professor Yeung, who is also President of the International Children's Continence Society.