My maternal grandmother at 46.
BUT…I am unable to have a live birth ages 37-40, ten natural losses and LOTs of arrested and abnormal embryos later!
Having quizzed both leading embryologists (part if a Harvard study) and urologists, eggs and sperm are going massively downhill. What your grandmother was exposed to (even in utero), what your mother was exposed to in utero etc, will all be impacting on your egg quality, decades later! They all tell me that plastic exposure is behind the gradual decline of human fertility. They have known for years. Even if my children (if I have any) are never exposed to those things in their lifetime, they will still be affected, through the generations. Your children and their children will have more problems as it passes down. It’s a ticking time bomb they say but despite lobbying, governments aren’t interested (short-termism).
So the fact that my grandma managed it, doesn’t mean I will - her grandmother and mother were exposed to far less plastic etc.