Background:
N/A

Objectives:
One of the leading causes of maternal mortality in the U.S. is pregnancy-related hypertension (PRH), a common complication of pregnancy associated with adverse maternal and fetal outcomes. Chronic hypertension preceding pregnancy (CHP) has also been associated with pre-eclampsia and eclampsia. We examined the national trend in hospitalizations for PRH at delivery and maternal outcome among women 15-54 years.

Methods:
National Hospital Discharge Survey (NHDS) data from 1995 through 2004 were used to assess changes in hospitalization rates among women ages 15-54 years at delivery of their live-born or stillborn infant. PRH includes pregnancy-induced hypertension (PIH) and CHP. Hospitalization rates of PRH, PIH and CHP (per 1,000 deliveries) were calculated. Differences between the years 1995-99 and 2000-04 were assessed in maternal outcome (death and length of medical care) among those hospitalizations with PRH at delivery. Relative percent change (RPC) was used to assess differences between 2 time periods in hospitalization rates

Results:
Overall, there were 38,808,148 deliveries in U.S. during 1995-2004. Hospitalization rates of PRH at delivery increased from 61.7 in 1995 to 79.9 in 2004, a RPC of 29.4% (p<0.05). For PIH the rates steadily increased from 48.0 in 1995 to 62.3 in 2004 (RPC=29.9%, p<0.05). For CHP the rates increased from 14.2 in 1995 to 18.0 in 2004 (RPC=27.3%, p<0.05). During 1995-1999 3.0/1,000 hospitalized women with PRH received extended medical care at discharge. This increased to 5.6/1,000 hospitalizations at deliveries during 2000-2004, a RPC of 88.0%. The PRH hospitalizations at delivery with deaths decreased from 0.4/1,000 in 1995-99 to 0.2/1000 in 2000-04 (RPC=-56.0%).

Conclusion and implications for practice:
PIH and CHP increased in the U.S. from 1995 to 2004, resulting in overall 29% increase in PRH. The number of PRH hospitalizations at delivery reporting extended medical care increased while deaths decreased from 1995-99 to 2000-04. Causes of the increase should be explored and further research required to assess hypertension awareness among reproductive age women prior to pregnancy to ascertain those at risk. Additionally, prevention and intervention of PRH must be pursued to reduce maternal illness and pregnancy complications.