Hello, Thanks for writing to Health Care magic, I am Dr , Muhammad Ahmad , I have read your question closely, I understand your concern and will be helping you with your health related problem. Such white discharge in pregnancy is very common in fungal infections, You don t need specifically an ultrasound for that but you do need to get a medical checkup with a doctor and start using anti fungal medication prescribed by your doctor. Usually fungal infections are not a dangerous in a normal healthy person they can well be controlled by using simple medication and topical creams, there is nothing to panic about, it wont need extensive tests to detect and start treatment for. I hope this answered your question, If you have more queries I am happy to answer you. Regards. Dr.Muhammad Ahmad