I've a cat I took responsibility for a year ago. He is now 2 years old. He was 'fixed' before I got him. He was never declawed. He is usually REALLY good about not scratching furniture or things he shouldn't. Until Saturday morning. I left my closet open a crack, and he is a curious fellow, and loves the closet for some reason.
Ovarian dysgenesis is a major cause of premature menopause. Ovarian dysgenesis is seen in 30% of the cases.[3] Sex chromosome anomalies predominate as a cause. The commonest abnormality is 45X0 (Turner's syndrome). Chromosomal abnormalities are reported in 10-20% of cases involving X sex chromosomes.[3]
1 Changes in the levels of these two hormones happen when the ovaries, for unknown reasons, prematurely stop releasing eggs. When this happens before the age of 40, it's called premature ovarian failure. Unlike premature menopause, premature ovarian failure is not always permanent.  Induced menopause.