Chronic heart disease and severe obstetric
morbidity among hospitalisations for pregnancy
in the USA: 1995–2006
EV Kuklina,aWM Callaghanb
aDivision of Heart Disease and Stroke Prevention andbDivision of Reproductive Health, National Center for Chronic Disease Prevention and
Health Promotion, Centers for Disease Control and Prevention, Atlanta, GA, USA
Correspondence: Dr EV Kuklina, Centers for Disease Control and Prevention, 4770 Buford Highway NE, Mailstop K-37, Atlanta, GA 30341-
3724, USA. Email firstname.lastname@example.org
The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for
Disease Control and Prevention.
Accepted 15 August 2010. Published Online 22 November 2010.
Objectives To describe changes in characteristics of delivery and
postpartum hospitalisations with chronic heart disease from 1995
Design Cross-sectional study.
Setting USA, nationwide hospital discharge data.
Population A total of 47 882 817 delivery hospitalisations and
660 038 postpartum hospitalisations.
Methods Adjusted odds ratios describing the associations between
chronic maternal heart disease and severe obstetric complications
were obtained from multivariable logistic models. The
contribution of chronic heart disease to severe morbidity was
estimated using adjusted population-attributable fractions.
Main outcome measures Prevalence and trends in chronic heart
disease, rate and risk of severe obstetric complications.
Results In 2004–2006, about 1.4% of delivery hospitalisations were
complicated with chronic heart disease. No substantial changes in
the overall prevalence of chronic heart disease among
hospitalisations for delivery were observed from 1995–1997 to
2004–2006. Even so, a linear increase was found for specific
congenital heart disease, cardiac dysrhythmias, and
cardiomyopathy and congestive heart failure (P < 0.01). During
this same period the rate of postpartum hospitalisations with
chronic heart disease tripled (P < 0.01). Severe complications
during hospitalisations for delivery among women with chronic
heart disease were more common in 2004–2006 than in 1995–
1997. In 2004–2006, 64.5% of the cases of acute myocardial
infarction, 57.5% of the instances of cardiac arrest/ventricular
fibrillation, 27.8% of in-hospital mortality and 26.0% of the cases
of adult respiratory distress syndrome were associated with
hospitalisations with chronic heart disease.
Conclusions In the USA chronic heart disease among women
hospitalised during pregnancy may have increased in severity from
1995 to 2006.
Keywords Epidemiology, heart diseases, pregnancy.
Please cite this paper as: Kuklina E, Callaghan W. Chronic heart disease and severe obstetric morbidity among hospitalisations for pregnancy in the USA:
1995–2006. BJOG 2011;118:345–352.
According to the most recent data available, heart disease is
the leading indirect cause of maternal mortality in the
developed countries.1,2Moreover, in some countries the
number of maternal cardiac deaths has actually risen in
recent years. For example, such deaths increased substan-
tially in the UK between 1986–1988 and 2003–2005.3Ratio-
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importance of chronic heart disease in the obstetric popu-
lation, data on its epidemiology are scarce.8Clearly, deter-
mining the prevalence (and trends) of chronic heart disease
among pregnant women in the USA could be a useful first
step toward understanding this problem.
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