What causes menopause is variable. So we know that menopause happens when a woman runs out of ovulation eggs. So we are born with the maximum number of O sites or eggs that we will ever have. And each month we ovulate or each month that we're ovulating, we will ovulate out in egg and ultimately through aging and through various factors that lead to decline in the ovarian function, we will end up with no more eggs to ovulate. Now it is interesting that, for example, if we're on a birth control pill, we don't ovulate eggs and therefore we may actually save some eggs, but that doesn't mean that we prolong the menopause or the time when our ovaries will decide they're finished. And so factors such as smoking or health conditions, factors like chemotherapy or radiation, or even some surgeries will impact the function of the ovaries and surgeries that remove the ovaries, obviously create immediate perimenopause and menopause because there's no more ovarian function. There's no more ovarian hormones from the ovaries and, and a woman's body will ultimately enter menopause as soon as the ovaries are removed. But other surgeries, for example, a woman who's had a hysterectomy, but her ovaries remain intact, will sometimes have earlier menopause because the blood supply to those ovaries may be impacted in that surgery. And just mainly to a slightly earlier menopause, certain medications can lead to menopause. And for some people there's this term called premature ovarian failure, which can mean that the ovaries stop working at a very young age, or in fact, in some cases they don't start working at all.