Blood pressure is the measure of pressure in the arteries for both the diastolic and systolic phases as the heart pumps blood to the body. Blood pressure is expressed in fraction-like numbers. The systolic pressure is represented as the top number in blood pressure reading and it’s the amount of pressure generated by the heart through pumping of blood to the rest of the body. The diastolic pressure is the bottom number and indicates the amount of pressure in your arteries when your heart relaxes between beats. When a woman is pregnant, her circulatory system expands rapidly. The blood pressure may drop and this is a normal phenomenon. Eventually, the blood pressure returns to your pre-pregnancy level after you have given birth.

Blood Pressure and Pregnancy

Blood pressure is a vital indicator of your health and most doctors will use it more often when diagnosing your problem. Any level of your blood pressure, low or high may indicate that things may not be fine with your body.

If the blood pressure escalates, it can damage some organs. For instance, during pregnancy, elevated blood pressure may damage the placenta, the baby’s only food supply chain. This results in slow growth and even retardation of the growth of the baby in the womb.

If the blood pressure goes down, it means that there will not be enough blood reaching the tissues and organs. The pregnant mother may faint sometimes due to inadequate blood reaching the brain to supply oxygen. The baby may also get limited amount of oxygen due to this condition. It is important to note that blood pressure changes may be prevalent especially during pregnancy; it is caused by the hormonal changes occurring in the body. And in case the pregnant woman shows some signs of blood pressure changes, it is a problem that should be looked at keenly.

What’s Considered Low Blood Pressure During Pregnancy?

Low blood pressure may occur during pregnancy, the systolic reading may drop by 5-10 mm Hg while the diastolic pressure may drop by about 10-15mm Hg. Actually, the readings may vary depending on the overall general health and your past medical history. The table below shows low blood pressure readings during pregnancy.

Severity Level

Systolic Pressure

Diastolic Pressure

Extremely low BP



Low BP (mild)

60 mmHg


Borderline low BP



Causes of Low Blood Pressure During Pregnancy

When you are pregnant, there will be an increased flow of blood in your body to maintain the supply of oxygen and food nutrients to the fetus. This causes your body’s blood pressure to decrease. It can be said that, this is the major cause of low blood pressure or hypotension in most pregnant women. However, there also exist other causes, which include having twins, a medical history of hypotension or low blood pressure or underlying medical illnesses such as dehydration, certain heart diseases and anemia. In addition, factors such as vitamin B12 or folic acid deficiency maybe responsible for low blood pressure, as well as lying on bed for prolonged duration. The administration of epidural may often lead to a drop in the blood pressure.

Symptoms of Low Blood Pressure During Pregnancy

The extent to which blood pressure falls is variable, but in most of the pregnant mothers, the diastolic pressure may drop by up to 15mm Hg while the systolic pressure may drop by about 5-10mm Hg. These lowered systolic and diastolic pressures may last during the pregnancy period and everything goes back to normal afterwards. These symptoms of low blood pressure are not different from any one with low blood pressure whether pregnant or not pregnant, and they include:

  • Dizziness and lightheadedness especially if you stand up abruptly from a sitting position
  • Blurred vision
  • Nausea
  • Concentration difficulty
  • Excessive thirst
  • Pale, clammy and cold skin
  • Fatigue and weakness
  • Elevated heart rate

How to Deal with Low Blood Pressure During Pregnancy

Pregnant women will experience dizziness due to low blood pressure; however, you can try these simple steps to minimize the symptoms as well as promote safety.

  • Try to lie on your left side as it increases the flow of blood to your heart
  • Avoid some sudden movement particularly when standing up from a seated position
  • Avoid standing for long durations of time
  • Wear support stockings, usually compression stockings
  • Avoid caffeinated drinks or beverages and alcohol
  • Consume several small meals during the day instead of the normal three large meals
  • Exercise regularly because it sharpens the reflexes and helps keep the blood pressure within the normal range. Consult with your physician regarding the exercises you can do while pregnant.
  • Drink plenty of fluids; a pregnant woman should drink more water than the recommended amount for normal people, usually drink between three quarts and a gallon of water a day.

When to Call the Doctor

In case the condition gets out of hand, you can always seek for professional help from your medical health care provider. Dizziness may be associated with troubling symptoms which should be observed keenly. It is recommended that any pregnant woman access emergency care in case she starts fainting, or starts experiencing more serious symptoms i.e. severe headache, blurring, weakness or numbness on one side of the body and shortness of breath.