My dad was 50 when I was born and died when he was 84, when I was 34.
Amongst my peers everyone bar one still had their dad at the time, but I think that would be very different for any baby born now with so many born later through IVF, and people generally having kids later.
There are pros and cons to having kids late or early, my Dad was incredibly patient and during my teenage rebel years, he had just retired, so was always around just to hang out. I think mature people can connect to younger people in ways you just can't in your 40’s or even 50’s.
My mother was your age OP when she had me, 46, and is still going strong, lives alone, no dementia and in her late 80’s.
Some have posted here that its cruel to expect kids in their 20's to care for elderly parents, but you can't live with what if's, most people aren't needing to be looked after 24 hours at 70 , when your baby will be 25. The average age for someone needing care is around mid 80's , that's long after any baby you have will be in their 20's. We all can get ill early, everything is a gamble, but its unlikely at least any child will need to care for you in their 20's all things being equal.
I think you should use the embryo, the real pain for kids born to older parents is they lose them relatively young and don’t have any grandparents for their own kids. My kids WORSHIP their grandma, but I know in 10 years, when they are still only teenagers she’ll more than likely have passed away. I also feel down sometimes they will never know their grandpa, I think for people like me having siblings is more important than other people who have 'young' parents.
I would look at the big picture, have you very young cousins, nephews and nieces that a child born when you’re 46 can bond with? Having another sibling for your current child will help them. I have brothers and sisters, I was the last one born in my family and the support of them REALLY helped when we lost Dad.
So I'll go against the grain and say not only should you go for it, if it doesn't work do consider adoption, maybe of a child a couple of years younger, or even donor egg / donor embryo, my point is for children of older parents, having a family network is very important.
Good luck x