What happens to our body after the age of 30?
A natural dip in estrogen and progesterone levels at about age 35 can cause your cycle to change—it might be shorter or longer, lighter or heavier, or earlier or later than usual. Some women also enter perimenopause (the transitional phase before menopause) as early as their latr 30s, and that also bring on period changes, says ob-gyn Jessica Shepherd, MD, assistant professor of clinical obstetrics and gynecology at the University of Illinois College of Medicine.