BACKGROUND AND PURPOSE:

• Bruno et al. (Obstetrics and Gynecology, 2022) evaluated national trends in hypertensive disorders of pregnancy (HDP), chronic hypertension and eclampsia using vital statistics data

METHODS:

• Repeated cross-sectional analysis
  • Data derived from the National Vital Statistics System (NVSS), from 1989 to 2020
• Population
  • Singleton pregnancies
  • Delivered >20 weeks
• Definitions
  • Hypertensive disorders of pregnancy: Increase in blood pressure in pregnancy inclusive of hypertensive disorders of pregnancy, preeclampsia, eclampsia, and HELLP syndrome
  • Chronic hypertension: Blood pressure elevation before pregnancy
  • Eclampsia as any hypertension with generalized seizures or coma
• Primary outcomes
  • Temporal trends in HDP, chronic hypertension, and eclampsia

RESULTS:

• Overall 122,329,914 deliveries
  • Cesarean: 26%
  • Nulliparous: 40%
  • Obesity: 26%
  • Mean maternal age: 28 years

Proportion of deliveries associated with HDP and chronic hypertension increased significantly over the study period

• HDP
  • 1989: 2.79% of pregnancies
  • 2020: 8.22% of pregnancies
  • Average annual percentage change: 3.6% (95% CI, 3.0 to 4.1)
• Chronic hypertension
  • Average annual percentage change: 4.1% (95% CI 3.3 to 4.9)

Proportion of deliveries associated with eclampsia declined significantly over the study period

• Eclampsia
  • 1989: 0.42%
  • 2020: 0.27%
  • Average annual percentage change: −2.5% (95% CI, −4.0 to −1.0)

Limited to 2016 to 2022

• Similar trends noted for HDP and chronic hypertension
• Decreasing trends for eclampsia were no longer significant

Nulliparity

• Results did not differ when analyses restricted to nulliparous individuals

CONCLUSION:

• The incidence of pregnancies complicated by HDP and chronic hypertension is increasing, while the rate of eclampsia decreased
• The authors state

It is unknown whether clinical practice changes or population-level risk factors altered these rates

Nonetheless, it is concerning that rates of hypertensive disorders continue to increase given the associated maternal morbidity and mortality

Learn More – Primary Sources:

Trends in Hypertensive Disorders of Pregnancy in the United States From 1989 to 2020

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