Clinical manifestations, risk factors, and maternal and perinatal outcomes of coronavirus disease 2019 in pregnancy: living systematic review and meta-analysis

BMJ. 2020 Sep 1;370:m3320. doi: 10.1136/bmj.m3320.

Abstract

Objective: To determine the clinical manifestations, risk factors, and maternal and perinatal outcomes in pregnant and recently pregnant women with suspected or confirmed coronavirus disease 2019 (covid-19).

Design: Living systematic review and meta-analysis.

Data sources: Medline, Embase, Cochrane database, WHO COVID-19 database, China National Knowledge Infrastructure (CNKI), and Wanfang databases from 1 December 2019 to 26 June 2020, along with preprint servers, social media, and reference lists.

Study selection: Cohort studies reporting the rates, clinical manifestations (symptoms, laboratory and radiological findings), risk factors, and maternal and perinatal outcomes in pregnant and recently pregnant women with suspected or confirmed covid-19.

Data extraction: At least two researchers independently extracted the data and assessed study quality. Random effects meta-analysis was performed, with estimates pooled as odds ratios and proportions with 95% confidence intervals. All analyses will be updated regularly.

Results: 77 studies were included. Overall, 10% (95% confidence interval 7% to14%; 28 studies, 11 432 women) of pregnant and recently pregnant women attending or admitted to hospital for any reason were diagnosed as having suspected or confirmed covid-19. The most common clinical manifestations of covid-19 in pregnancy were fever (40%) and cough (39%). Compared with non-pregnant women of reproductive age, pregnant and recently pregnant women with covid-19 were less likely to report symptoms of fever (odds ratio 0.43, 95% confidence interval 0.22 to 0.85; I2=74%; 5 studies; 80 521 women) and myalgia (0.48, 0.45 to 0.51; I2=0%; 3 studies; 80 409 women) and were more likely to need admission to an intensive care unit (1.62, 1.33 to 1.96; I2=0%) and invasive ventilation (1.88, 1.36 to 2.60; I2=0%; 4 studies, 91 606 women). 73 pregnant women (0.1%, 26 studies, 11 580 women) with confirmed covid-19 died from any cause. Increased maternal age (1.78, 1.25 to 2.55; I2=9%; 4 studies; 1058 women), high body mass index (2.38, 1.67 to 3.39; I2=0%; 3 studies; 877 women), chronic hypertension (2.0, 1.14 to 3.48; I2=0%; 2 studies; 858 women), and pre-existing diabetes (2.51, 1.31 to 4.80; I2=12%; 2 studies; 858 women) were associated with severe covid-19 in pregnancy. Pre-existing maternal comorbidity was a risk factor for admission to an intensive care unit (4.21, 1.06 to 16.72; I2=0%; 2 studies; 320 women) and invasive ventilation (4.48, 1.40 to 14.37; I2=0%; 2 studies; 313 women). Spontaneous preterm birth rate was 6% (95% confidence interval 3% to 9%; I2=55%; 10 studies; 870 women) in women with covid-19. The odds of any preterm birth (3.01, 95% confidence interval 1.16 to 7.85; I2=1%; 2 studies; 339 women) was high in pregnant women with covid-19 compared with those without the disease. A quarter of all neonates born to mothers with covid-19 were admitted to the neonatal unit (25%) and were at increased risk of admission (odds ratio 3.13, 95% confidence interval 2.05 to 4.78, I2=not estimable; 1 study, 1121 neonates) than those born to mothers without covid-19.

Conclusion: Pregnant and recently pregnant women are less likely to manifest covid-19 related symptoms of fever and myalgia than non-pregnant women of reproductive age and are potentially more likely to need intensive care treatment for covid-19. Pre-existing comorbidities, high maternal age, and high body mass index seem to be risk factors for severe covid-19. Preterm birth rates are high in pregnant women with covid-19 than in pregnant women without the disease.

Systematic review registration: PROSPERO CRD42020178076.

Readers' note: This article is a living systematic review that will be updated to reflect emerging evidence. Updates may occur for up to two years from the date of original publication.

Publication types

  • Meta-Analysis
  • Research Support, Non-U.S. Gov't
  • Systematic Review

MeSH terms

  • Betacoronavirus*
  • Coronavirus Infections* / diagnosis
  • Coronavirus Infections* / epidemiology
  • Coronavirus Infections* / etiology
  • Coronavirus Infections* / therapy
  • Female
  • Global Health / statistics & numerical data
  • Humans
  • Infant, Newborn
  • Intensive Care, Neonatal / statistics & numerical data
  • Pandemics*
  • Pneumonia, Viral* / diagnosis
  • Pneumonia, Viral* / epidemiology
  • Pneumonia, Viral* / etiology
  • Pneumonia, Viral* / therapy
  • Pregnancy
  • Pregnancy Complications, Infectious* / epidemiology
  • Pregnancy Complications, Infectious* / etiology
  • Pregnancy Complications, Infectious* / therapy
  • Premature Birth / epidemiology
  • Premature Birth / virology
  • Prognosis
  • Risk Factors

Supplementary concepts

  • COVID-19
  • severe acute respiratory syndrome coronavirus 2