Background: There are extensive evidence that preeclampsia is the reason for many maternal and perinatal morbidities. However, there are no previous study on the different outcomes in severe preeclamptic women between new onset hypertension and chronic hypertension.

Objective: To compare the rate of low Apgar score at 5 minutes and other adverse pregnancy outcomes of preeclamptic women with severe features between those who had new onset hypertension in pregnancy and those with chronic hypertension before pregnancy.

Materials and Methods: A retrospective cohort study was conducted. The medical records of pregnant women diagnosed with preeclampsia with severe features and delivered at Chonburi Hospital between January 2017 and June 2020 were reviewed. The authors categorized these pregnant women into two groups, new onset hypertension and chronic hypertension. Descriptive statistics were used for the data analyses.

Results: Of the 526 women diagnosed with preeclampsia with severe features, 290 met the inclusion and exclusion criteria. Eighty-nine had superimposed preeclampsia on chronic hypertension and 201 patients had new onset hypertension. The rate of low Apgar score at 5 minutes was not statistically different between the two groups (p=0.258). The incidence of impaired liver function and HELLP syndrome were increased in the new onset hypertension group at 18.9% versus 6.7% (p=0.008) and 9.5% versus 1.1% (p=0.010), respectively.

Conclusion: There was no significant difference in the rate of low Apgar score between the two groups. Regarding the severity of maternal outcomes, new onset preeclampsia with severe features seems to be more severe than superimposed preeclampsia on chronic hypertension.

Keywords: Low Apgar score; Preeclampsia with severe features; Chronic hypertension; Superimposed preeclampsia; Pregnancy outcomes

DOI: doi.org/10.35755/jmedassocthai.2021.06.12379

Received 28 December 2020 | Revised 17 March 2021 | Accepted 22 March 2021