Ovarian reserve denotes the size of the ovarian follicle pool .And also the quality of oocytes inside them .
This reserve declines with age and hence reproductive function in females also decreases.
During fetal life, ovaries contain several millions of follicles. Around 2.5 million follicles are present at birth, which decreases to 3-4 lakh at puberty. And with aging only few follicles are left in the late 40’s. Finally at menopause there are no follicles present in the ovaries.
Amh is the clinical marker of this ovarian reserve.
Throughout the life , follicles grow to pre antral and antral stages . Majority of these follicles are lost due to atresia.
After puberty , HPO ( hypothalamus pituitary ovarian) axis gets activated, and there is aggressive production of FSH .
( follicle stimulating hormone)
FSH stimulates the follicles to grow but only one dominant follicle is selected in each cycle.
This dominant follicle gets ruptured to release the egg, as a consequence of the mid cycle LH surge . This is called as ovulation.
Now as this proces continues, there comes a time when the primordial follicle pool gets exhausted. This is menopause .
But nowadays, we see that before the age of menopause, the ovarian reserve is getting exhausted. And the functioning of ovaries is lost .
This functional failure of ovaries is called as
Premature ovarian failure .