As such, in early pregnancy, transient hypotension
can cause syncopal attacks. Since you have hypothyroidism
, the basal metabolic rate
of your system would be low; you have associated bradycardia also. Though your body would be functioning without any trouble in the normal state, in the pregnant condition there is increased metabolism and demands rise; as such your body is probably not able to cope with the raised demand and you pass out. You need proper evaluation from a cardiologist and an endocrinologist
for future management. Wish you good health.