Question on fertility rates on glow

Julie • 37 year old woman trying to conceive. Lost my baby boy from trisomy 18 n have 2 beautiful children.
I know the other you get the lesser chance but on glow for women 25-35 is the percentage on where it says day of period or ur ovulating days is the percentage higher? I'm 38 n have 21 percent chance what are some other of younger age?