Thanks for your query.
Boy’s testicles normally descend from within the abdomen into the
scrotum before birth. Around 3% of boys are born with their testicles undescended (not within the scrotum).
At six months of age and beyond only about 0.8% of boys have undescended testicles. That means in other about 2.2 % the testicles descend down into scrotum by 6 months.
Sometimes a testicle may move back and forth between the scrotum and the groin and when so called retractile testicle is residing in the groin, it may be easily guided by hand into its proper position in the scrotum during a physical examination.
For most boys, the problem of a retractile testicle goes away sometime before or during
puberty, the time when an out-of-place testicle moves to its correct location in the scrotum and stays there permanently.
Ultrasound and
MRI are not generally helpful in determining whether testes are retractile or not. It is in fact only by clinical examination similar to how his mum was asked to assist.
The definitive treatment of truly
undescended testes is by surgery ideally around one year of age.
Hope you find the information helpful.