Is high blood pressure in pregnancy linked to later health risks?

As many as 15% of women who become pregnant develop either gestational hypertension or pre-eclampsia. Gestational hypertension is defined as high blood pressure that appears after 20 weeks gestation without other clinical signs of pre-eclampsia, which is a potentially life-threatening condition for both mother and child.

Women who develop gestational hypertension or pre-eclampsia nearly always see their blood pressures return to normal after delivery, but it seems from several small studies that such women still have a greater risk of developing high blood pressure, poor cholesterol scores, or even type 2 diabetes.

An article just published in the Annals of Internal Medicine (doi:10.7326/M17-2740) makes use of data gathered from the Nurses' Health Study II, which began in 1989 and enrolled over 115,000 women between the ages of 25 and 42. Every two years the participants respond to detailed questionnaires regarding their health and lifestyle - including pregnancies and conditions such as high blood pressure, cholesterol scores, and medications.

For their research, the authors of this study excluded women who had never reported a pregnancy as well as those whose first pregnancy was before the age of 18 or after the age of 45. Similarly, they also excluded women who reported having hypertension, diabetes, poor cholesterol scores, heart attack, or stroke before their first pregnancy. This left over 55,000 women in their sample.

The questionnaire the participants received in 1989 asked them to report on their pregnancy history, including diagnoses of gestational hypertension, gestational diabetes, or pre-eclampsia. For nearly two-thirds of these women, the authors were able to verify their self-reported diagnoses by reviewing their medical records. From 1989 onwards the participants also reported any diagnosis of (non-gestational) high blood pressure, whether they developed type 2 diabetes, and whether they were taking cholesterol-lowering medication.

After taking into account variables such as age at first birth, race/ethnicity, amount of physical activity, family history of high blood pressure or diabetes, Body Mass Index before pregnancy, overall diet quality, alcohol use, and smoking history, the authors found that those who developed gestational hypertension were almost 3 times as likely to become hypertensive later in life, 65% more likely to develop type 2 diabetes, and 36% more likely to have poor cholesterol scores.

Women who had pre-eclampsia in their first pregnancy were just over twice (2 times) as likely to develop high blood pressure, 75% more likely to develop diabetes, and 30% more likely to experience poor cholesterol scores.

What this means for you

You might be wondering what this has to do with food. Perhaps the most significant step a prospective mother can take to ensure a healthy pregnancy is to follow a healthy diet before they get pregnant - one that helps reduce their risk of high blood pressure and diabetes and improves their cholesterol scores.

A Mediterranean-style diet has been shown to do all of these things - and you can still eat great food. Here's more information on what a Mediterranean-style diet looks like. Or take the Mediterranean Diet Score Quiz, which includes tips on how you might improve it.

First posted: July 11, 2018