key: cord-0963720-msdyb2nb authors: Shi, Li; Wang, Ying; Yang, Haiyan; Duan, Guangcai; Wang, Yadong title: Laboratory Abnormalities in Pregnant Women with Novel Coronavirus Disease 2019 date: 2020-05-12 journal: Am J Perinatol DOI: 10.1055/s-0040-1712181 sha: 6ba188dc4b6b003fd85c4bab9c3e0d7eb716dadb doc_id: 963720 cord_uid: msdyb2nb nan Novel coronavirus disease 2019 , sustained by the causative agent called severe acute respiratory syndromecoronavirus-2 (SARS-CoV-2), is highly contagious. 1,2 At present, above 2 million confirmed cases and over 170,000 deaths of COVID-19 have occurred in the world according to the World Health Organization. 3 Pregnant women, because of their special physiological conditions, are susceptible to the virus and put themselves at greater risk. 4 Timely control and treatment of pregnant women with COVID-19 infection are a major concern. 5 Moreover, laboratory medicine plays a vital role in this process. 6 Therefore, the purpose of this article is to identify the most common laboratory abnormalities in pregnant women with COVID-19. PubMed, Chinese National Knowledge Infrastructure (CNKI), and Wanfang databases were reviewed by two independent authors, using the keywords "coronavirus" OR "Wuhan coronavirus" OR "SARS-CoV-2" OR "2019 novel coronavirus" OR "2019-nCoV" OR "COVID-19" AND "pregnancy" OR "pregnant woman" OR "pregnant women" OR "vertical transmission" (up to April 20, 2020). There were no country, race, or language restrictions. We included articles reporting laboratory data in pregnant women with confirmed COVID-19 by reading titles, abstracts, and full texts. Besides, the lists of references for all articles were also screened to identify potentially additional articles. A descriptive statistical analysis was applied to summarize their findings. A random-effects model meta-analysis was then carried out to calculate the pooled prevalence and 95% confidence interval (95% CI) to assess the prevalence of laboratory abnormalities in pregnant women with COVID-19. Double arcsine method was implemented to make original data conform to normal distribution, and then we analyzed them in software Stata version 11.2 to obtain initial results. Final results were restored by the formula (P ¼ [sin (tp/2)] 2 ). 7 Begg's test and Egger's test were utilized to evaluate publication bias. A total of 244 articles were reviewed, among which 223 were removed due to a lack of laboratory data about pregnant women. Although eight articles reported laboratory data in pregnant women with COVID-19, they were eliminated because of duplicated data. In addition, two articles that did not clearly report laboratory abnormalities were also excluded. Overall, a total of 11 articles with 173 pregnant patients were included, 8-18 among which 11 women had severe disease, and 2 women had critical disease. Most of the patients came from China, and one each came from Korea, the United States, Sweden, Iran, Peru, and Canada. The stages of pregnancy ranged from the first trimester to the third trimester. The characteristics of these patients are indicated in ►Table 1. Four articles were included in the meta-analysis. 9,10,15,16 Our results indicated that among all laboratory parameters of pregnant women with COVID-19, the incidence of elevated D-dimer was 82% (95% CI: 75-89%), elevated neutrophil count was 81% (95% CI: 69-91%), elevated C-reactive protein was 69% (95% CI: 58-79%), and decreased lymphocyte count was 59% (95% CI: 41-75%). Begg's test and Egger's test showed that no publication bias existed (►Table 2). No other laboratory parameters showed apparently consistent changes due to the limitation of available data. Considering the relatively high-sequence identity of SARS-CoV-2 and SARS-CoV and the effects of SARS-CoV on pregnant women, we must pay great attention to the group of pregnant women infected with COVID-19. 19, 20 Our review suggests that the most frequent abnormalities are elevated D-dimer (82%), elevated neutrophil count (81%), elevated C-reactive protein (69%), and decreased lymphocyte count (59%). However, a meta-analysis of adult COVID-19 infection reported that Table 1 Characteristics of the included studies Note: laboratory data are presented as percent of patients with abnormalities defined by local reference ranges. 21 Our study found that the incidence of increased LDH in pregnant women with COVID-19 was only 29%. A total of seven cases reported by Wang et al, 17 Iqbal et al, 12 and Chen et al 10 showed decreased albumin levels. Similarly, only Lee et al 13 described that ESR increased in the pregnant woman with COVID-19. Due to the limitation of the data, we did not further conduct a meta-analysis on these laboratory parameters. Thus, more studies with large sample size are needed to discuss this in the future. In addition, Zhang et al 22 reported that among five pregnant women with SARS-CoV infection, two cases had decreased lymphocytes. Recent studies also reported elevated D-dimer levels, elevated neutrophil count, elevated C-reactive protein levels, and decreased lymphocyte count as indicators of poor outcomes in nonpregnant individuals with COVID-19. 23 We should pay careful attention to these laboratory indicators of pregnant women with COVID-19. However, D-dimer was typically elevated during pregnancy, 24 and a comparative cross-sectional study revealed that pregnant women had significantly higher white blood cell count, neutrophil count, and lymphocyte count compared with nonpregnant women. 25 Therefore, pregnancy factors should also be considered when dynamically monitoring changes of laboratory indicators in pregnant women with COVID-19. Of course, our review has some limitations. We included only 11 articles, including case reports and case series, and most of them were from China. Again, reference ranges for laboratory values differed between reports and several data elements were not clearly reported. In addition, most of the pregnant women with COVID-19 included in our review were mild and moderate, with only 11 cases being severe and 2 cases being critical. We were unable to compare laboratory abnormalities between pregnant women with mild and severe. So, more data from other regions are needed to better define laboratory abnormalities in pregnant women with COVID-19 infection. In our meta-analysis, elevated D-dimer levels, elevated neutrophil count, elevated C-reactive protein levels, and decreased lymphocyte count are the most prevalent laboratory abnormalities in pregnant women with COVID-19, which is slightly different from the characteristics in nonpregnant patients. We should consider pregnancy factors when monitoring changes in pregnant women. What we know so far: COVID-19 current clinical knowledge and research A familial cluster of pneumonia associated with the 2019 novel coronavirus indicating person-toperson transmission: a study of a family cluster World Health Organization. Coronavirus disease (COVID-2019) situation reports-94 Clinical characteristics and intrauterine vertical transmission potential of COVID-19 infection in nine pregnant women: a retrospective review of medical records What are the risks of COVID-19 infection in pregnant women? A modern and pragmatic definition of Laboratory Medicine Clinical characteristics of hospitalized patients with SARS-CoV-2 infection: A single arm meta-analysis Severe COVID-19 during pregnancy and possible vertical transmission Clinical characteristics of pregnant women with COVID-19 in Wuhan, China Clinical analysis of pregnant women with 2019 novel coronavirus pneumonia COVID-19 in pregnancy with comorbidities: More liberal testing strategy is needed An uncomplicated delivery in a patient with COVID-19 in the United States Emergency cesarean section on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) confirmed patient Lack of vertical transmission of severe acute respiratory syndrome coronavirus 2 Clinical and CT imaging features of the COVID-19 pneumonia: Focus on pregnant women and children COVID19 and acute coagulopathy in pregnancy A case of 2019 Novel Coronavirus in a pregnant woman with preterm delivery Preterm delivery in pregnant woman with critical COVID-19 pneumonia and vertical transmission Potential maternal and infant outcomes from (Wuhan) coronavirus 2019-nCoV infecting pregnant women: lessons from SARS, MERS, and other human coronavirus infections Potent binding of 2019 novel coronavirus spike protein by a SARS coronavirus-specific human monoclonal antibody Clinical, laboratory and imaging features of COVID-19: A systematic review and meta-analysis Hematologic, biochemical and immune biomarker abnormalities associated with severe illness and mortality in coronavirus disease 2019 (COVID-19): a meta-analysis Pregnancy and laboratory studies: a reference table for clinicians Hematological indices of pregnant women at the university of gondar referral hospital, Northwest Ethiopia: a comparative cross-sectional study This study was supported by a grant from the National Natural Science Foundation of China (no.: 81973105). None declared.