How Are Blood Pressure And Pregnancy Related

Blood pressure In Pregnancy

Blood pressure is one of the parameters your gynecologist will check during every prenatal visit. It is normal to have a slight dip in your blood pressure during pregnancy, especially in the first and second trimesters. This can be attributed to the hormone progesterone that relaxes the walls of the blood vessels. A feeling of dizziness may overcome you while standing up for too long or too quickly. As your blood supply increases (by about a liter) to cater to the needs of the growing baby, your blood pressure will also rise from the 24th week of pregnancy.

Procedure To Measure The Blood Pressure

Your doctor will have a machine to measure your blood pressure. They will wrap a cuff around your arm above the elbow and pump air into it. It feels tight on the arm though it doesn’t hurt. The pumping stops, and the air in the cuff is released slowly. The machine then records and displays your blood pressure.
There are two readings on the display, which are in the form of a fraction. For instance, 120/80. The numerator or the reading above is the systolic blood pressure (when the heart pumps the blood around the body), whereas the denominator or the reading at the bottom is the diastolic blood pressure (when the heart relaxes between the beats). Do not compare your results with other moms-to-be as the normal levels could slightly differ from person to person.


High blood Pressure

The normal blood pressure is between 110/70 and 120/80, but, again, it may vary during pregnancy. In case of high blood pressure, you may need to undergo further tests and your blood pressure will be monitored every hour for 3-4 hours. The doctor will diagnose you with high blood pressure if

  • Your pressure readings are 140/90 or higher for 2 measures that are taken 4 hours apart.
  • Your diastolic blood pressure shows a constant reading of 110 or higher. It is the diastolic pressure that is the true indicator of your health. So, if this figure alone is higher, the person is said to have high blood pressure.

High blood pressure during pregnancy can be attributed to two reasons:

  • Being diagnosed with high blood pressure before the 20th week of pregnancy is possibly a pre-existing condition of high blood pressure, probably even before you conceived. This is called chronic hypertension. To ensure you had it previously, you might have to wait until after your baby is born and again go for a pressure checkup.
  • High blood pressure during pregnancy, which is mostly after the 20th week is called gestational hypertension and is solely restricted to the gestation period. It is not a matter of much concern, though you may need to consult a specialist.

Importance Of Measuring Blood Pressure

Your blood pressure determines how your pregnancy proceeds. High blood pressure can be an indicator of a pregnancy complication like pre-eclampsia—when the placenta does not perform its function very well. Though the scientists are still trying to figure out the exact cause and impact of pre-eclampsia, it has been linked to high blood pressure during pregnancy. But, it is not necessary that moms with high blood pressure will develop this condition. Chronic hypertension and gestational hypertension can only increase the risks.
Hence, it becomes important that moms get their blood pressure checked regularly. You can also ask your health expert to give you more information on pre-eclampsia and any symptoms that you must look out for.

Blood Pressure After Birth

Your doctor will check your blood pressure at least once within 6 hours after delivery. If you had gestational diabetes then your pressure will be monitored over the next few days. Usually, it will become normal after giving birth, however, if that doesn’t happen you may be prescribed medicines that are safe to take while breastfeeding.


If you find yourself having a pre-existing high blood pressure or chronic hypertension, your medication will probably continue post delivery.