Home blood pressure in pregnancy-the upper reference limit

Area of Science:

• Obstetrics and Gynecology
• Cardiovascular Health
• Hypertension Research

Background:

• The diagnosis of white coat hypertension in pregnancy often relies on a blood pressure threshold of 135/85 mmHg.
• Establishing accurate reference limits for home blood pressure monitoring in pregnant populations is crucial for effective management.

Purpose of the Study:

• To determine the upper reference limit for home blood pressure in healthy pregnant women.
• To assess if the established limit aligns with the 135/85 mmHg threshold used for white coat hypertension diagnosis outside of pregnancy.

Main Methods:

• A prospective observational study included 103 healthy singleton pregnant women.
• Home blood pressure was measured twice daily for three days using a validated device, alongside routine office measurements.
• Upper blood pressure reference limits were calculated as mean +2 SD.

Main Results:

• Office blood pressure readings were consistently higher than home blood pressure readings across all trimesters.
• In late pregnancy, the upper reference limit for office blood pressure was 140/91 mmHg.
• In late pregnancy, the upper reference limit for home blood pressure was determined to be 123/78 mmHg.

Conclusions:

• The upper home blood pressure reference limit in healthy pregnant women during late pregnancy is 123/78 mmHg.
• This established limit suggests that the commonly used 135/85 mmHg threshold may not be appropriate for diagnosing white coat hypertension in pregnant individuals.