Introduction: Rate of weight gain during early childhood may have an effect on timing of puberty in girls. Biological mechanisms underlying this condition are not fully understood. Studies examining this association in boys report contradictory results. Our aim was to examine the effects of growth rate during the first years of life on the onset of puberty both in girls and boys.
Description of methods: 159 children aged between 6 and 9 years who were attending the Well Child Clinic between the ages of 1 month and 5 years were included in the study. Anthropometric measurements during the follow-up were obtained from childrens files. Weight, height, waist and hip circumferences were measured and pubertal staging was done at the time of investigation at a mean age of 7.6±0.9 years. Blood samples for LH, FSH and estradiol/testosterone were collected. Breast and pelvic ultrasonography was done.
Results: 21.2% of girls had breast enlargement before the age of 8 years, 17.6% had breast enlargement between 8 and 9 years, and 7.1% had premature pubarche. 12.2% of boys had testicular enlargement starting before the age of 9 years and 7.1% had premature pubarche. The average BMI SDS and waist circumference SDS of girls demonstrating findings of puberty were significantly higher (P=0.001 and P=0.03). Girls having an accelerated weight gain between 6 and 15 months of age demonstrated precocious puberty signs more often (P=0.007) and at the ages of 69 years their average BMI SDS were higher compared to the peers (P=0.01). Boys having an accelerated linear growth between 9 and 15 months of age demonstrated pubertal findings more frequently (P=0.004).
Conclusions: Our results suggest that early growth acceleration is important for the timing of puberty in both sexes but the girls and boys with precocious puberty showed different growth patterns and probably different mechanisms.
20 - 22 Sep 2014
European Society for Paediatric Endocrinology