Early puberty can lead to a reduction in final adult height because high estrogen levels close growth plates approximately two years after ovulation begins.

“so not only are we seeing a change in this getting starting earlier what we're also seeing is probably some reduction in height from having gone through puberty at an earlier process because once you start actually menstrating once the ovaries have really started to learn how to respond to that FSH and grow the follicle and it gets to the point where you can start ovulating so about two years later then that ovulatory period those high levels of estrogen are going to go and they're going to close those growth plates so you've really started to limit your final adult height as well when you go through puberty earlier”