Anterior fontanelle closure time in 684 healthy Portuguese children


  • Ricardo Craveiro Costa Medical Genetics Unit, Hospital Pediátrico, Unidade Local de Saúde de Coimbra
  • Joana Rosmaninho Salgado Medical Genetics Unit, Hospital Pediátrico, Unidade Local de Saúde de Coimbra
  • Daniela Oliveira Medical Genetics Unit, Hospital Pediátrico, Unidade Local de Saúde de Coimbra
  • Francisca Mendes Family Medicine, Unidade de Saúde Familiar – Briosa
  • Alexandre Silva Instituto Politécnico de Coimbra-Coimbra Business School - CEISUC- Centro de Estudos e Investigação em Saúde da Universidade de Coimbra
  • Manuel Salgado Ambulatory Pediatrics Unit, Hospital Pediátrico, Unidade Local de Saúde de Coimbra



child, cranial fontanelle, development, growth, pediatrics


Introduction and Aim: The timing of anterior fontanelle (AF) closure may be a useful marker for early disease detection. However, the few published studies on this topic have reported significant differences in the normal age ranges of AF closure between countries. The aim of this study was to report AF closure time in the Portuguese population during the last two decades.
Methods: This was a 21-year retrospective observational study of healthy Portuguese children conducted from January 1999 to December 2019. Data on the age of AF closure were collected by a single pediatrician during outpatient child visits at specific ages (1, 2, 4, 6, 9, 12, 18, 24, 30, and 36 months) and during unscheduled visits due to appointment changes or illness. Clinically closed AF was defined as the absence of a depressible fontanelle on physical examination. AF closure time was calculated as the mean age between the age of the last palpable AF and the age of the first clinically closed AF.
Results: A total of 684 children (gestational age ≥37 weeks, birth weight ≥2500 grams) were evaluated, of whom 364 (53.2%) were boys. The mean ± 1 standard deviation (SD) age of AF closure was 14.3 ± 4.9 months (range 2−33 months). The 2.5th and 97.5th percentiles, representing ± 2 SD of AF closure time, were 6 and 25 months, respectively. Other percentiles were P5 - 7 months, P25 - 11 months, P50 - 14 months, P75 - 16 months, and P95 - 22 months. Noteworthy, 0.6% and 3.1% of children had a closed AF at three and six months, respectively, while 2.9% still had an open AF at 24 months. AF closure occurred earlier in males than in females (13.6±4.7 vs. 15.1±5.0, p <0.001). A statistically significant difference was found in the mean ± 2 SD of the gender comparison (p=0.045).
Conclusions: This study showed a normal distribution of AF closure age in Portuguese children. The acknowledgment of age-related variations in AF closure timing in different populations is important to raise clinicians’ awareness for timely suspicion and detection of pathologic cases and the need for clinical study.


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How to Cite

Costa RC, Rosmaninho Salgado J, Oliveira D, Mendes F, Silva A, Salgado M. Anterior fontanelle closure time in 684 healthy Portuguese children. REVNEC [Internet]. 2024Jun.27 [cited 2024Jul.23];33(2):95-9. Available from:



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