What Are The Chances Of Conceiving At The Age Of 38?

Hi. I am 38 yrs old with 2 kids 13 and 7 yrs. Been trying to get pregnant for the last 2years. i have taken clomid for 3 cycles with no success, had a pelvic scan with normal results and hsg done before i started on clomid. Doc suggest that i take ova-mit. please help, any chances of me conceiving some day?