Impact of COVID-19 on pregnant women in South Korea: Focusing on prevalence, severity, and clinical outcomes

Abstract

Background In the era of coronavirus disease 2019 (COVID-19) pandemic, there is a paucity of information regarding actual prevalence of COVID-19 in pregnant women compared to non-pregnant women. The purpose of this study was to investigate the prevalence of COVID-19 infection and clinical outcome in pregnant women and non-pregnant women. Methods This is a nationwide cross-sectional study in South Korea between January 2020 and February 2021 using the claim database. The primary outcome was the prevalence of COVID-19 in pregnant women, and the secondary outcome was the occurrence of severe COVID-19 illness among infected patients. Severity of COVID-19 was classified into four categories according to WHO ordinal scale. Results The prevalence of COVID-19 infection was lower in pregnant women than non-pregnant women aged 20-44 (0·02% vs. 0·14%, p<0.0001). However, among COVID-19 positive women at age 20-44, pregnant women was at higher risk of oxygen therapy after hospitalization (score 4 in WHO ordinal scale: 6.4% vs. 1.6%, p<0.05). There were no deaths or hospitalized severe disease in pregnant women with COVID-19, although the majority of them (96·2%) were admitted to hospital. On the other hand, 42·3% of non-pregnant women at 20-44 age were admitted to hospital and 0·04% of them died and 0·1% had hospitalized severe disease. Conclusions The prevalence of COVID-19 infection in pregnant women was lower than non-pregnant women in Korea, resulting in relatively small cases of fatality. It has implications that public health policy, such as an effective response to COVID-19 and a powerful preemptive strategy for pregnant women, can lower risk of COVID-19 infection and better clinical outcomes in pregnant women with COVID-19.

Impact of vaccination and the omicron variant on COVID-19 severity in pregnant women

“…Since the emergence of coronavirus disease 2019 (COVID-19) in February 2020, the number of pregnant women infected with the virus and delivering by cesarean section has been steadily increasing in South Korea. 1 Additionally, pregnancy is considered a high-risk factor for severe COVID-19, 2 especially in case of infection with the delta variant of SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2). Despite reports showing a more favorable disease outcome with the omicron variant, little is known about its clinical course in pregnant women.…”

Maternal and Neonatal Outcomes in Pregnant Women With Coronavirus Disease 2019 in Korea

“…17 Furthermore, the severity of COVID-19 in pregnant women is similar to that in non-pregnant women. 13 14 18 19 20 21 22 23 24 25 26 27 28…”

COVID-19 and pregnancy: epidemiology, clinical features, maternal and perinatal outcomes. A systematic review

“…According to Kim S.H. et al (2022), pregnant women are not at increased risk of COVID-19 infection and the incidence among them is lower than in non-pregnant women aged 20-44 years (0.02% vs. 0.14%, p < 0.0001) [16]. The authors emphasize that asymptomatic forms of the disease are not uncommon, especially in the absence of screening examinations, which does not allow identifying the true extent of the spread of the disease.…”

“…Despite a low incidence compared to non-pregnant women of reproductive age, pregnant women require hospitalization more often, have a significantly higher risk of severe form of COVID-19 with the need for observation in the ICU (Kim S.H. et al [16]: 6.4% vs. 1, 6%, p < 0.05, Ellington S. et al [17]: аdjusted risk ratio (aRR) = 1.5, 95% confidence interval (CI) = 1.2-1.8 [16,17]. According to Zha L. et al (2022), in pregnant women compared with non-pregnant women COVID-19 is characterized by a milder course, and Parums D.V.…”

“…Some studies suggest that the maternal death rate is higher in a cohort of pregnant women with COVID-19 as opposed to controls (Epelboin S. et [16,18,53] or differences in groups between pregnant and non-pregnant women were not found to be significant (Ellington S. et al (2020) [17]: aRR = 0.9, 95% CI = 0.5-1.5). Given the lack of consensus between studies on this issue, when planning antenatal care, it is reasonable to assume pregnancy as being a risk factor for severe disease making these women more at risk of requiring ICU admission, mechanical ventilation, extracorporal membrane oxygenation, and having a greater mortality risk than non-pregnant women of reproductive age, should they develop COVID-19 infection [57,58].…”