hii.. congratulations on your pregnancy. i understand your concern. salicylic acid is an active ingredient of many cosmetic and acne creams. But the products that you have been using contain topical salicylic acid (local applications like skin, scalp) and percentage, strength of it is very low. so relatively only small portions are absorbed locally through the skin. this do not cause any major risk to the developing baby. As you said the ultrasound and screening tests were fine then you need not worry about your baby. hope this cleared your doubts, have a good health.. thank you.