For the duration of one to six months of pregnancy, a lot of women experience a low blood pressure during pregnancy. This is because their body is adjusting to the increase in the circulatory blood volume because of the presence of the developing fetus.
With proper management, this can be resolved. But if neglected it can cause signs and symptoms that can be dangerous to both the mother and the fetus. As the blood pressure increases constantly, pregnant mothers will experience dizziness.
Also, pregnant women are not advised to lie on their backs because the enlarged fetus may compress large blood vessel causing a decrease in blood pressure. You can prevent this by side-lying position.
A decrease in blood pressure can be cause by dehydration of the mother because of the increase circulatory needs of both the mother and baby. It is advisable to increase oral fluid intake to prevent this from happening.