In 1933 one of us (Lewis1) showed that by administering estrogenic substance it was possible to change the thin vaginal mucosa of the child to that resembling the thick epidermis-like structure of the adult. This change is a temporary one and subsides when treatment is withdrawn, with a reversion to the normal vaginal mucosa characteristic of childhood. Together with the report of this observation were recorded eight cases of gonorrheal vaginitis in children, treated with estrogenic substance. Most of these were treated with hypodermic injections of aqueous solutions of the principle. In some, estrogen suppositories were used as adjuvants. All were improved and some cured.
Later we2 reported that the building up of the vaginal mucosa in this way produced a strongly acid vaginal secretion like that of the adult menstruating woman. Before puberty and after the cessation of ovarian activity the vaginal mucosa is a delicate thin
LEWIS RM, ADLER EL. ENDOCRINE TREATMENT OF VAGINITIS OF CHILDREN AND OF WOMEN AFTER THE MENOPAUSE. JAMA. 1937;109(23):1873–1875. doi:10.1001/jama.1937.02780490011004