Identification of factors associated with delayed treatment of obstetric hypertensive emergencies

Published:February 14, 2020DOI:


      Obstetric hypertensive emergency is defined as having systolic blood pressure ≥160 mm Hg or diastolic blood pressure ≥110 mm Hg, confirmed 15 minutes apart. The American College of Obstetricians and Gynecologists recommends that acute-onset, severe hypertension be treated with first line-therapy (intravenous labetalol, intravenous hydralazine or oral nifedipine) within 60 minutes to reduce risk of maternal morbidity and death.


      Our objective was to identify barriers that lead to delayed treatment of obstetric hypertensive emergency.

      Study Design

      A retrospective cohort study was performed that compared women who were treated appropriately within 60 minutes vs those with delay in first-line therapy. We identified 604 patients with discharge diagnoses of chronic hypertension, gestational hypertension, or preeclampsia using International Classification of Diseases–10 codes and obstetric antihypertensive usage in a pharmacy database at 1 academic institution from January 2017 through June 2018. Of these, 267 women (44.2%) experienced obstetric hypertensive emergency in the intrapartum period or within 2 days of delivery; the results from 213 women were used for analysis. We evaluated maternal characteristics, presenting symptoms and circumstances, timing of hypertensive emergency, gestational age at presentation, and administered medications. Chi square, Fisher’s exact, Wilcoxon rank-sum, and sample t-tests were used to compare the 2 groups. Univariable logistic regression was applied to determine predictors of delayed treatment. Multivariable regression model was also performed; C-statistic and Hosmer and Lemeshow goodness-of-fit test were used to assess the model fit. A result was considered statistically significant at P<.05.


      Of the 213 women, 110 (51.6%) had delayed treatment vs 103 (48.4%) who were treated within 60 minutes. Patients who had delayed treatment were 3.2 times more likely to have an initial blood pressure in the nonsevere range vs those who had timely treatment (odds ratio, 3.24; 95% confidence interval, 1.85–5.68). Timeliness of treatment was associated with presence or absence of preeclampsia symptoms; patients without preeclampsia symptoms were 2.7 times more likely to have delayed treatment (odds ratio, 2.68; 95% confidence interval, 1.50–4.80). Patients with hypertensive emergencies that occurred overnight between 10 pm and 6 am were 2.7 times more likely to have delayed treatment vs those emergencies that occurred between 6 am and 10 pm (odds ratio, 2.72; 95% confidence interval, 1.27–5.83). Delayed treatment also had an association with race, with white patients being 1.8 times more likely to have delayed treatment (odds ratio, 1.79; 95% confidence interval, 1.04–3.08). Patients who were treated at <60 minutes had a lower gestational age at presentation vs those with delayed treatment (34.6±5 vs 36.6±4 weeks, respectively; P<.001). For every 1-week increase in gestational age at presentation, there was a 9% increase in the likelihood of delayed treatment (odds ratio, 1.11; 95% confidence interval, 1.04–1.19). Another factor that was associated with delay of treatment was having a complaint of labor symptoms, which made patients 2.2 times as likely to experience treatment delay (odds ratio, 2.17; 95% confidence interval, 1.07–4.41).


      Initial blood pressure in the nonsevere range, absence of preeclampsia symptoms, presentation overnight, white race, having complaint of labor symptoms, and increasing gestational age at presentation are barriers that lead to a delay in the treatment of obstetric hypertensive emergency. Quality improvement initiatives that target these barriers should be instituted to improve timely treatment.

      Key words

      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'


      Subscribe to American Journal of Obstetrics & Gynecology
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect


        • American College of Obstetricians and Gynecologists
        Task Force on Hypertension in Pregnancy. Hypertension in pregnancy: report of the American College of Obstetricians and Gynecologists’ Task Force on hypertension in pregnancy.
        Obstet Gynecol. 2013; 122: 1122-1131
        • Creanga A.A.
        • Syverson C.
        • Seed K.
        • Callaghan W.M.
        Pregnancy-related mortality in the United States, 2011-2013.
        Obstet Gynecol. 2017; 130: 366-373
        • Leeman L.
        • Dresang L.T.
        • Fontaine P.
        Hypertensive disorders of pregnancy.
        Am Fam Physician. 2016; 93: 121-127
        • Hitti J.
        • Sienas L.
        • Walker S.
        • et al.
        Contribution of hypertension to severe maternal morbidity.
        Am J Obstet Gynecol. 2018; 219: 405.e1-405.e7
        • Say L.
        • Chou D.
        • Gemmill A.
        • et al.
        Global causes of maternal death: a WHO systematic analysis.
        Lancet Glob Health. 2014; 2: e323-e333
        • Shahul S.
        • Tung A.
        • Minhaj M.
        • et al.
        Racial disparities in comorbidities, complications, and maternal and fetal outcomes in women with preeclampsia/eclampsia.
        Hypertens Pregnancy. 2015; 34: 506-515
        • Too G.T.
        • Hill J.B.
        Hypertensive crisis during pregnancy and postpartum period.
        Semin Perinatol. 2013; 37: 280-287
        • Vadhera R.B.
        • Simon M.
        Hypertensive emergencies in pregnancy.
        Clin Obstet Gynecol. 2014; 57: 797-805
        • ACOG Committee on Obstetric Practice
        Emergent therapy for acute-onset, severe hypertension during pregnancy and the postpartum period.
        Committee Opinion No. 767. Obstet Gynecol. 2019; 133: 409-412
        • Nathan H.L.
        • Seed P.T.
        • Hezelgrave N.L.
        • et al.
        Early warning system hypertension thresholds to predict adverse outcomes in pre-eclampsia: a prospective cohort study.
        Pregnancy Hypertens. 2018; 12: 183-188
        • Martin J.N.
        • Thigpen B.D.
        • Moore R.C.
        • et al.
        Stroke and severe preeclampsia and eclampsia: a paradigm shift focusing on systolic blood pressure.
        Obstet Gynecol. 2005; 105: 246-254
        • Bernstein P.S.
        • Martin J.N.
        • Barton J.R.
        • et al.
        National partnership for maternal safety: consensus bundle on severe hypertension during pregnancy and the postpartum period.
        Obstet Gynecol. 2017; 130: 347-357
        • Shields L.E.
        • Wiesner S.
        • Klein C.
        • et al.
        Early standardized treatment of critical blood pressure elevations is associated with a reduction in eclampsia and severe maternal morbidity.
        Am J Obstet Gynecol. 2017; 216: 415.e1-415.e5
        • Ackerman C.M.
        • Platner M.H.
        • Spatz E.S.
        • et al.
        Severe cardiovascular morbidity in women with hypertensive diseases during delivery hospitalization.
        Am J Obstet Gynecol. 2019; 220: 582.e1-582.e11
        • Troiano N.H.
        • Witcher P.M.
        Maternal mortality and morbidity in the united states: Classification, causes, preventability, and critical care obstetric implications.
        J Perinat Neonatal Nurs. 2018; 32: 222-231
        • Miller E.C.
        Preeclampsia and cerebrovascular disease.
        Hypertension. 2019; 74: 5-13
        • New York State Department of Health
        Hypertensive disorders New York State Department of Health Executive - Guideline Summary.
      1. Safe Motherhood Initiative. Maternal safety bundle for severe hypertension in pregnancy. American College of Obstetricians and Gynecologists District II; 2018.

        • Moroz L.A.
        • Simpson L.L.
        • Rochelson B.
        Management of severe hypertension in pregnancy.
        Semin Perinatol. 2016; 40: 112-118
        • Cleary K.L.
        • Siddiq Z.
        • Ananth C.V.
        • et al.
        Use of antihypertensive medications during delivery hospitalizations complicated by preeclampsia.
        Obstet Gynecol. 2018; 131: 441-450
        • Beatty C.A.
        • Dangel A.
        Timely discharge: oral nifedipine is superior to labetalol for postpartum BP control in patients with preeclampsia.
        Obstet Gynecol. 2018; 131: 201S-202S
        • Alavifard S.
        • Chase R.
        • Janoudi G.
        • et al.
        First-line antihypertensive treatment for severe hypertension in pregnancy: a systematic review and network meta-analysis.
        Pregnancy Hypertens. 2019; 18: 179-187
        • Raheem I.A.
        • Saaid R.
        • Omar S.Z.
        • Tan P.C.
        Oral nifedipine versus intravenous labetalol for acute blood pressure control in hypertensive emergencies of pregnancy: a randomised trial.
        BJOG. 2012; 119: 78-85
        • Rezaei Z.
        • Fatemeh R.S.
        • Pourmojieb M.
        • et al.
        Comparison of the efficacy of nifedipine and hydralazine in hypertensive crisis in pregnancy.
        Acta Med Iran. 2011; 49: 701-706
        • Magee L.A.
        • Pels A.
        • Helewa M.
        • et al.
        Diagnosis, evaluation, and management of the hypertensive disorders of pregnancy.
        J Obstet Gynaecol Can. 2014; 36: 575-576
        • Vermillion S.T.
        • Scardo J.A.
        • Newman R.B.
        • Chauhan S.P.
        A randomized, double-blind trial of oral nifedipine and intravenous labetalol in hypertensive emergencies of pregnancy.
        Am J Obstet Gynecol. 1999; 181: 858-861
        • Shekhar S.
        • Sharma C.
        • Thakur S.
        • Verma S.
        Oral nifedipine or intravenous labetalol for hypertensive emergency in pregnancy: a randomized controlled trial.
        Obstet Gynecol. 2013; 122: 1057-1063
        • Bushnell C.
        • McCullough L.D.
        • Awad I.A.
        • et al.
        Guidelines for the prevention of stroke in women: a statement for healthcare professionals from the American Heart Association/American Stroke Association.
        Stroke. 2014; 45: 1545-1588
        • Cotton D.B.
        • Gonik B.
        • Dorman K.F.
        Cardiovascular alterations in severe pregnancy-induced hypertension: acute effects of intravenous magnesium sulfate.
        Am J Obstet Gynecol. 1984; 148: 162-165
        • D’Alton M.E.
        • Friedman A.M.
        • Bernstein P.S.
        • et al.
        Putting the “M” back in maternal-fetal medicine: a 5-year report card on a collaborative effort to address maternal morbidity and mortality in the United States.
        Am J Obstet Gynecol. 2019; 221: 311-317
        • Menzies J.
        • Magee L.A.
        • Li J.
        • et al.
        Instituting surveillance guidelines and adverse outcomes in preeclampsia.
        Obstet Gynecol. 2007; 110: 121-127
        • Clark S.L.
        • Hankins G.D.V.
        Preventing maternal death: 10 clinical diamonds.
        Obstet Gynecol. 2012; 119: 360-364
        • Peberdy M.A.
        • Omato J.P.
        • Larkin G.L.
        • et al.
        Survival from in-hospital cardiac arrest during nights and weekends.
        JAMA. 2008; 299: 785-792
        • Knuist M.
        • Bonsel G.J.
        • Zondervan H.A.
        • Treffers P.E.
        Risk factors for preeclampsia in nulliparous women in distinct ethnic groups: a prospective cohort study.
        Obstet Gynecol. 1998; 92: 174-178
        • Goodwin A.A.
        • Mercer B.M.
        Does maternal race or ethnicity affect the expression of severe preeclampsia?.
        Am J Obstet Gynecol. 2005; 193: 973-978