Hypotension - Low Blood Pressure and Pregnancy
Hypertension and pre-eclampsia are two concerns that are common in pregnancy and require adequate treatment in order to ensure a healthy outcome for both mother and baby. Hypertension, high blood pressure, in pregnancy has been extensively studied and as a result, treatments and protocols have been established based on the findings of research and practical experience.
Hypotension and Pregnancy Outcomes
However, little attention has been given to the other end of the spectrum, low blood pressure or hypotension. In a study done in 1977 on pregnancy hypertension, it was found that about 10 percent of the women studied had a low diastolic blood pressure (DBP) and that low systolic blood pressure combine with low diastolic blood pressure were associated with a higher risk for the following health issues:
· low birth weight
· fetal death
· defective intelligence quotient scores at age 4
No further analysis was performed vis-à-vis hypotension. These findings have consistently been cited in literature and agreed with other data at the time. But there was something missing in the assessments.
To understand a little more about hypotension, it is important to know a bit about what the numbers represent in a blood pressure reading. Blood pressure (BP) is the measurement of the pressure in your arteries during the active and resting phases of each heartbeat. Here is what the numbers mean:
· Systolic pressure. This is the top number in a BP reading and indicates the amount of pressure the heart generates when pumping blood through the arteries to the rest of the body.
· Diastolic pressure. The bottom number on the reading refers to the amount of pressure in the arteries when the heart is at rest between beats.
The current guidelines for normal blood pressure show blood pressure that is equal to or lower than 120/80. Many experts think 115/75 is better. However, blood pressure changes frequently in a short period of time and is dependent upon body position, breathing levels, medication being taken, time of day and the physical condition of the individual. (Mayo Clinic)
A New Study on Hypotension and Pregnancy Outcomes
Back to the study mentioned earlier - a later study done in 2000 on low blood pressure during pregnancy and poor pregnancy outcomes looked at data that had been collected over a period of seven years, from 1959 to 1966 and of the nearly 59,000 women in that study, determined 28,095 subjects were eligible. They wanted to determine if poor pregnancy outcomes were indeed associated with low blood pressure. The specific outcomes they investigated were preterm births (less than 34 weeks) and severe small for gestational age (SGA) being less than the 5th percentile.