Why do ovaries start to fail us women so young? I was prepared to start ttc at 35 but postponed till 40 and needed donor eggs.

AGE. It is our biggest nemesis in fertility treatment. Egg age is one of the only non correctable problems we face. It's sad but the common knowledge out there and the message from the medical system fails to warn women that fertility begins to fall in the late 20's and rapidly in normal women at 35-38. If one has endometriosis, diminished ovarian reserve will be a significant problem in early 30's.