hi, my age is 34, i am thyroid patient but my report is fine i have taken 75 mg from last 6 years, i have 5 years old baby,with 27 days(fix circle)i don't have any fertility problem as per my doctor,circle length is ok,ovulation day is ok, egg size is ok, my husband reports is ok, but i cant conceive, i m try from last 18 months,what should i have taken next step?my fallopian tube test is ok and folical study is ok.....pls help