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[Development of anterior fontanelle in Chinese children in 2015]
1Department of Growth and Development, Capital Institution of Pediatrics, Beijing 100020, China.
Insights
The anterior fontanel (AF) in healthy Chinese children closes around 14.5 months, with size decreasing with age. Fontanel closure correlates positively with height and weight, but not head circumference.
Area of Science:
- Pediatrics
- Human Growth and Development
- Craniology
Background:
- The anterior fontanel (AF) is a key indicator of infant growth.
- Understanding AF development and closure is crucial for assessing physical development in children.
- Previous studies have established general timelines for AF closure, but regional and temporal variations require ongoing investigation.
Purpose of the Study:
- To document the developmental trajectory of the anterior fontanel (AF) in healthy Chinese children aged 1–36 months.
- To determine the mean age of AF closure and its associated percentile ranges.
- To investigate the relationship between AF closure and physical development parameters, including height, weight, and head circumference.
- To analyze secular trends in AF closure over 30 years (1985–2015).
Main Methods:
- A cross-sectional study involving 104,147 healthy Chinese children aged 1–36 months.
- Measurements of AF size and closure status were recorded.
- Probit analysis was used to calculate the age of AF closure.
- Data from 2015 were compared with historical data from 1985, 1995, and 2005.
Main Results:
- The mean AF size decreased with age, measuring 2.0 cm at 1 month and closing to 0.0 cm by 21–23 months.
- The mean age of AF closure was 14.5 months (95% CI: 14.4–14.6 months), with 3rd and 97th percentiles at 6.6 and 22.4 months, respectively.
- Significant positive correlations were observed between AF closure and increased height and weight (P<0.01), but not head circumference.
- No significant secular changes in the mean age of AF closure were found overall, though a trend towards earlier closure was noted in suburban areas.
Conclusions:
- The AF exhibits maximum size at 1 month, gradually decreasing with age, with a mean closure age of 14.5 months.
- AF development shows a positive correlation with height and weight, but not head circumference.
- Secular trends indicate stability in the mean age of AF closure over the past three decades.
Abstract:
Objective: To observe the development of the anterior fontanel (AF) in healthy Chinese children from 1 to 36 months, and to assess the relationship between the closure of the AF and physical development in Chinese children. Method: This was a cross-sectional evaluation of the AF in a series of 104 147 healthy children between June 2015 and October 2015 from nine cities in China. The size and closure of AF of the children were measured and recorded, and the age for the closure of AF was calculated using probit analysis. The data in 2015 were compared with the data from the same surveys in 1985, 1995 and 2005 respectively. Result: (1) Totally, 104 147 healthy children (52 216 boys and 51 931 girls; range 1 month to 36 months) from nine cities enrolled in this cross-sectional study. (2)The size of AF gradually decreased with age, and the mean size of AF was 2.0(95% confidence interval (CI)2.0-2.1) cm at the age of 1 month, 0.6(95% CI 0.5-0.6) cm at the ages of 12-14 months, and 0.0(95% CI 0.0-0.0) cm at the ages of 21-23 months, respectively. (3) The percentage for the closure of AF was 0.1% at the age of 3 months, 67.5% at the ages of 15-17 months. The oldestt age for closure was 35 months. The mean age for the closure of AF was 14.5 months (95% CI 14.4-14.6), and the 3rd and 97th centiles of the age for the closure of AF were 6.6 and 22.4 months. (4) Over the past 30 years from 1985 to 2015, no significant change was found regarding the mean age for the closure of AF in children from urban area, contrarily, the mean age was 1.1 months earlier in suburban area. (5) The height and weight of children in the closed AF group were significantly higher than those of children in unclosed AF group(all P<0.01), but no significant difference was found regarding the head circumference between the two groups. Conclusion: The size of AF at 1 month was maximum, then decreases gradually with age, and the mean age for the closure of AF was 14.5 (95% CI 14.4-14.6) months. No significant correlation was found between the development of AF and the head circumference, but there was a positive correlation between the development of AF and the height and weight. There was no significant change regarding the secular trend of the age for the closure of AF.
