Hello, I have gone through your query and understood the concern. Transient hypotension is a common phenomenon during pregnancy due to the altered vascular state. You seem to be suffering from postural hypotension, but, other organic causes also have to ruled out. I would ask you to see a general physician for a proper assessment. In addition, if you have had a normal sonogram picture in compliance with your stage of pregnancy, check for abnormal blood pressure, electrolyte imbalances and anemia. further management can be planned accordingly. Hope this helps.