Minipuberty: Why Does it Happen?

Abstract

Minipuberty describes the transient sex-specific activation of the hypothalamic-pituitary-gonadal (HPG) axis during the first 6 months of life in boys and during the first 2 years in girls. It leads to a rise of luteinizing hormone, follicle-stimulating hormone, estradiol, and testosterone. The existence of minipuberty has been known for >40 years, but we still do not fully understand why it takes place. Current thinking suggests that it is an essential imprinting period for different body functions. Firstly, minipuberty plays an important role in genital organ development; testosterone influences penile growth, the number of Sertoli cells, and spermatogenesis. Secondly, it seems to influence the infant's body composition; testosterone likely has an imprinting effect on BMI and body weight of boys and growth velocity in the first 6 months of life. Thirdly, it affects cognitive functions; testosterone has an impact on language organization in the infant brain and estradiol affects laryngeal sound production and baby babbling. There are inconsistent findings concerning the impact of minipuberty on sex-specific playing behavior. Minipuberty is an interesting field of research, and further studies in this area will teach us more about this exciting period of human development.

Keywords: Estradiol; Gonadotropin; Hypothalamic-pituitary-gonadal axis; Minipuberty; Testosterone.