Introduction: Due to the COVID 19 pandemic and home confinement measures, many of our routine and daily habits have been both affected and modified. Have these factors conditioned a real increase in Precocious (PP) and Accelerated Puberty (AP)?

Objectives: This is an observational and retrospective study in which the incidence of medical consultations due to Premature Thelarche is compared between March to December 2019 and 2020. The medical consultations occurred in the Pediatric Endocrinology (PE) consultation of our hospital.
Patients and Methods: The analysis involved 75 cases of young girls consulted with Premature Thelarche in 2019 and 97 girls which were consulted in 2020. From each patient different variables were analyzed, such as somatometry, hormones, eco and treatment.

Results: In 2019, 75 first visits of PE were due to Premature Thelarche in young girls (accounting for 2.46% of the total number of first visits carried out in Pediatrics Outpatient Clinics (POC) and 16.77% of PE first visits). However, in 2020, 97 first visits were due to PE (3.52% the total first time visits of OC and 23.3% in PE). It was found that, in 2020 the number of first time visits due to Premature Thelarche increased by 28% compared to 2019 (p = 0.0001 mean comparison).
In 2019, out of the 75 consultations due to premature Thelarche, 40% were diagnosed with an earlier physiological puberty. Conversely in 2020, out of the 97 consultations, 61.77% had a normal physiological puberty. These figures represent an OR of 1.54 (p = 0.02 t Student for independent samples). It was evaluated whether the patients had experienced > 3 kg weight gain above 6 months prior to the medical visit. In 2020, 31.57% of patients experienced weight gain, whereas 68.42% did not. In 2019 patients who experienced weight gain accounted for 12.16% and 87.83% did not experience significant weight gain (p = 0.01 t Student for independent samples).

Conclusion: Our data demonstrates there has been an increase in the incidence of the referrals from Primary Attention to Pediatric Endocrinology to examine advanced Thelarche during the period of lockdown measures (2020), in addition to an increase in the number of diagnostics of PP and AP in young girls in our hospital when compared to figures of 2019. Furthermore, in 2020 there was a greater number of patients who experienced weight gain increase 6 months prior to the medical consultations.

We hypothesize that lockdown inflicted sedentary lifestyles together with changes in dietary habits, promoting weight gain in patients. This effect could have caused a body fat mass increase in girls, suggesting a “trigger effect” in the activation of the gonadal axis, causing a rise in the number of early puberty cases.