A first menstrual cycle usually occurs between the ages of 10 and 16 with the average age of a first period being 12.4 years old. That’s a pretty wide range, so how do you know when your kid needs ...

Puberty often begins at around 11 years old, although anywhere between about 8 and 14 is considered within the typical range. One of the hallmarks of puberty is getting a first period or beginning ...

There is unexpectedly large variation in height growth in girls after their first period. Every second girl grows either more or less in length than the 6-8 centimeters that is considered standard.