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CME Credit Offered
CME Credit Offered
Abstract Award
Abstract Award
Recording available 2/16-5/2
Recording available 2/16-5/2
AIUM Credit
AIUM Credit
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Foundation Awardee
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Abstract Award
Abstract Award
Foundation Awardee
Foundation Awardee

Poster Session 1

Category: Hypertension

Poster Session 1

(240) Evaluating the real-world impact of the CHAP trial on blood pressure control and perinatal outcomes

Wednesday, February 11, 2026
10:30 AM - 12:00 PM  
Objective:
The Chronic Hypertension and Pregnancy (CHAP) trial shifted paradigms around blood pressure (BP) control in pregnant women with chronic hypertension (CHTN). We assessed whether national and local recommendations to target BPs in pregnancy to < 140/90 mmHg resulted in lower blood pressure and improved perinatal outcomes using both cohort and time series analyses. 

Study Design:
We conducted a retrospective cohort study of all pregnant women with CHTN who initiated prenatal care with at least 2 prenatal visits prior to 20 weeks’ gestation and delivered at a single medical center between 1/1/2018 and 7/1/2024. The primary outcome was visit systolic blood pressure (SBP). Individual patient records were reviewed to assess composite outcomes from the CHAP trial. The p</span>re-Chap period spanned visits from 1/1/2018 through the CHAP trial publication (4/2/2022) and the post-CHAP period spanned 6-weeks after rollout of local guidelines for CHTN management (7/1/2022) through the end of the study period (7/1/2024). We conducted an interrupted time series analysis using mixed effects models to analyze the effects of guideline changes. 

Results:
Of 12,979 pregnancies meeting inclusion criteria, 556 (4.3%) had CHTN (346 deliveries pre-CHAP, 210 post-CHAP). On average, SBP decreased 0.020 mmHg (95% CI -0.027, -0.013) weekly during the study period. Guideline changes were associated with a 2.25 mmHg lower SBP (95% CI -4.19, -0.32) but no additional SBP decrease was noted after guidelines. Guideline changes were not associated with a decrease in the CHAP trial outcomes (Table 2). However, during the overall time period, each 1-unit decrease in SBP was associated with a 1.2% decreased risk for the CHAP trial outcomes (aRR -0.012, 95% CI -0.021, -0.002, p=0.014).

Conclusion:

In a real-world situation, average visit SBP decreased over a 6-year period and was impacted by national and local implementations of guidelines from the CHAP trial. The overall decrease in SBP was associated with a reduction in the composite outcome reported in the CHAP trial.