Typically, if elevated blood pressure (BP) is noted before the 20th week it is considered chronic or preexisting to the pregnancy. After 20 weeks pregnant, new onset blood pressure is often caused by chemicals released by the baby resulting in Preeclampsia or Pregnancy Induced Hypertension (PIH). Both diseases require additional baseline laboratories and fetal surveillance, i.e. ultrasounds and fetal heart monitoring in the office.
Chronic Hypertension usually requires medication throughout the pregnancy to keep it under control. Pregnancy Induced Hypertension may require blood pressure medication at the time of delivery, along with Magnesium Sulfate to prevent maternal seizures. Pregnancy Induced Hypertension is more common with your first baby, in people with preexisting chronic hypertension and in those who had Pregnancy Induced Hypertension with their previous pregnancy.