How To Avoid Birth Defects During Pregnancy And Which Are The Test To Detect Birth Defects ?

hi,i am 30 years i have one son his age is ight years he is a healthy boy.one year ago i had a girl but she had a serious problem in heart and died after operation of open heart.She was four months.really i didnot make the torch analysis orany typ of it.after another four months of her death i was pregnant again,it was a girl ,i didnot make any analysis also ,the sonar in every time of check show every thing ok,but when she was born she had a congenital defect in the two nostrils,they were blockd by inside she cannot breathe well and a problem in heart.she died in the sam day of birth .after making analysis of caryotypings, blood ,RH which is positive,and torch igm and igg,we discovered that i had all negative in igm but in igg rubella resulted 400 and cmv is 900, is this means a remains of infections because the level of antibodioes are very high and may b afected th baby in the second time because there was a short time between the first and th sedond girl.also i found that the anticardiolivin was positive in igm and igg and was high is this can afect the baby and what i shoud do now to dis cover the problem or when iam prgnant again thank you