Frequent Blood Pressure Monitoring Is Needed During and After Pregnancy

Health care providers must check pregnant patients’ blood pressure regularly, starting early in pregnancy and continuing for at least six weeks after childbirth, according to new draft recommendations from the U.S. Preventive Services Task Force.

The task force issued the draft recommendations on Tuesday amid growing concern about a rise in maternal mortality. Pregnancy-related deaths in the United States are the highest among industrialized nations, and hypertensive disorders of pregnancy are among the leading causes.

Blood pressure disorders in pregnancy have doubled in prevalence in the past three decades, affecting one in 10 pregnancies now, up from one in 20 in 1993. They are a leading cause of death during and after pregnancy among Native American women and the leading cause of death among Black women.

The groups face maternal mortality rates that are up to three times as high as those among white women. The disorders pose a high risk of stroke to Black and Hispanic women, the task force noted. Yet women of color were underrepresented in most clinical trials that tested screening regimens for the condition.

The task force called on health care providers to offer better support for pregnant women of color, and for physicians to be aware of their increased risks so they can “focus clinical energy and resources to those most likely to suffer morbidity or mortality.”

“Our moms are dying,” Dr. Wanda Nicholson, vice chair of the task force, said, adding that the new draft recommendations aimed “to call attention to the racial disparities in maternal deaths and morbidity.”

The recommendations call for more research into the conditions, and they urge doctors and midwives to use standard, evidence-based treatment for all patients. 

Not all pregnant women who are affected receive the recommended care for blood pressure disorders, though Black women are more likely to get appropriate care than white women.

“The take-home point is that we know, unequivocally, that consistent checking of blood pressure during pregnancy makes a difference for our moms and babies,” said Dr. Nicholson, a senior associate dean for diversity, equity and inclusion at the Milken Institute School of Public Health at George Washington University.

The onset of a severe blood pressure condition called pre-eclampsia/eclampsia often occurs after the first 20 weeks of pregnancy. Low-dose aspirin starting at 12 weeks gestation is recommended for women at heightened risk — a large group that includes patients with pre-existing conditions like diabetes or lupus, those who are 35 and older or under the age of 15, patients who have undergone in vitro fertilization, and those pregnant for the first time.

The report suggests all Black women who are pregnant and have at least one risk factor for pre-eclampsia/eclampsia should be put on low-dose aspirin, which may prevent or at least delay the development of the condition.

Patients with high blood pressure during pregnancy must be monitored very closely, said Dr. Christian Pettker, a professor of obstetrics, gynecology and reproductive science at Yale School of Medicine and a co-author of treatment guidelines for the American College of Obstetricians and Gynecologists.

“People who have elevated blood pressure in pregnancy are managed very differently than those who don’t,” Dr. Pettker said.

Health care providers should prescribe medication for the blood pressure, and run additional blood tests and urine tests to check for abnormalities, as well as fetal ultrasounds to monitor the baby’s growth, Dr. Pettker said.

In severe cases, the baby may be delivered early. Patients should report to their doctors symptoms including unusual headaches, sharp upper abdominal pain and blurry vision. The postpartum period is a critical one, as the risk of dying of a hypertensive disorder is highest then.

Dr. Pettker warned that there may be a tendency among some health providers to dismiss high blood pressure readings in pregnant patients because they are generally young and healthy. But that is a mistake.

“We sometimes try to normalize it — they look healthy, and seem to be doing great. But it might be an important signal,” Dr. Pettker said, adding that the medical community had “a lot of work to do to make sure that we take even mild blood pressure as a signal to pay attention to, and to pay attention in the same way for all the different people who present to us for prenatal care.”

Blood pressure disorders have potentially serious long-term repercussions for the mother and the baby, and they are linked to preterm births and stillbirths, as well as to a long-term risk of heart disease in the mother.

Hypertension can restrict fetal growth because it impedes blood flow, and can result in a medically induced preterm birth, because delivery of the baby resolves the disease and may be necessary to save the mother’s life and health.

Women who had pre-eclampsia when they delivered are also at high risk of developing heart failure after childbirth, and Black women are at double the risk of white women, according to new findings by Truveta Research, the research arm of Truveta, a for-profit collective of health systems that uses de-identified patient data for research.

Though the reasons for the disparity are not known, some may be caused by unequal access to care and by the failure of care givers to listen when women report unusual symptoms, Dr. Charlotte Baker, Truveta’s director of epidemiology, said. Dr. Baker lost a friend to the condition just months after the friend gave birth.

“My friend had complained multiple times to her physicians, but they brushed her off,” she said.

No one knows exactly why hypertensive disorders have doubled in prevalence in the past three decades, but women are having children at older ages than in the past. They are heavier than they used to be, as are all Americans, and a greater number have high blood pressure even before they become pregnant.

Living conditions, known as social determinants of health, also play a role in maternal health, and recent studies have implicated housing instability and food insecurity in blood pressure disorders and other pregnancy complications. Disparities in access to health care services may also play a role.

Maternal mortality rates in the United States have been rising in recent decades, and rose in 2021 to 1,178 deaths, up from 861 deaths in 2020, according to provisional figures in a recent Government Accountability Office report.