Hypertension in Pregnancy: Which Drug Is Best?

Caring for the hypertensive pregnant patient is a daunting challenge. With limited research into effective therapies and the ever-present risk of harm to the unborn child, nephrologists must rely on old science and good fortune to manage both mother and child. Delayed treatment can result in irreparable fetal harm, and often, early delivery is the only option available. With more research in this area, nephrologists and obstetricians can rely less on such extreme measures to protect mom and baby. In one of the few randomized trials involving pregnant women, researchers evaluated the efficacy and safety of three commonly used oral antihypertensive agents: nifedipine, labetalol, and methyldopa. Nearly 900 women in their third trimester with high systolic or diastolic blood pressure were randomly assigned to receive one of the three drugs.

Download here

Patients in the nifedipine arm were more likely to achieve the primary efficacy endpoint of control of both systolic and diastolic blood pressure within 6 hours of treatment initiation (without adverse events) compared with those in the methyldopa arm. The results were equivalent for women treated with labetalol or methyldopa, but patients in the former arm required fewer additional doses or additional antihypertensive medications to control their blood pressure. For patients who did not receive additional drugs, those assigned labetalol were more likely to achieve the primary endpoint than those on methyldopa. A closer look at the data shows that both the nifedipine and labetalol arms were more likely than the methyldopa group to reach target blood pressure within 3 hours.

Labor and delivery outcomes were no different among the three treatment groups. Neonatal outcomes were also similar except that more children were born at a low or very low birthweight in the nifedipine arm, resulting in a larger percentage of newborns to mothers on nifedipine being admitted to the intensive care unit (ICU). Thankfully, there was no difference observed in neonatal survival, need for mechanical ventilation, or length of stay in the ICU.

Overall this is an excellent study that highlights the value of nifedipine and labetalol over methyldopa. Patients were included in the third trimester (28 weeks gestational age) so it is unlikely that the results can be extrapolated to patients in the second trimester (20 weeks gestational age). The low birthweight of neonates in the nifedipine arm is concerning despite no differences in any other neonatal complication. Together, these data give us a better understanding of the efficacy and safety of nifedipine and labetalol, and a realization that either can replace methyldopa.

Tejas Desai is a practicing nephrologist in Charlotte, North Carolina. His academic interests include the use of social media for physician, student, and patient education. He is the founder of NOD Analytics, a free social media analytics group that serves the medical education community. He has two wonderful children and enjoys spending time with them and his wife.

Follow Tejas P. Desai, MD, on Twitter: @nephondemand

Follow Medscape on Facebook, Twitter, Instagram, and YouTube

Any views expressed above are the author's own and do not necessarily reflect the views of WebMD or Medscape.

Cite this: Tejas P. Desai. Hypertension in Pregnancy: Which Drug Is Best? - Medscape - Jun 10, 2020.

Commenting is limited to medical professionals. To comment please Log-in.

Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.