COVID-19 in Pregnancy: Influence of Body Weight and Nutritional Status on Maternal and Pregnancy Outcomes-A Review of Literature and Meta-Analysis

Abstract

In the last two and a half years, COVID-19 has been one of the most challenging public health issues worldwide. Based on the available evidence, pregnant women do not appear to be more susceptible to infection than the general population but having COVID-19 during pregnancy may increase the risk of major complications for both the mother and the fetus. The aim of this study is to identify the correlation between BMI and nutritional status and the likelihood of contracting COVID-19 infection in pregnancy, its severity, and maternal pregnancy outcomes. We carry out a systematic literature search and a meta-analysis using three databases following the guidelines of the Cochrane Collaboration. We include 45 studies about COVID-19-positive pregnant women. Compared with normal-weight pregnant women with COVID-19, obesity is associated with a more severe infection (OR = 2.32 [1.65-3.25]), increased maternal death (OR = 2.84 [2.01-4.02]), and a higher rate of hospital admission (OR = 2.11 [1.37-3.26]). Obesity may be associated with adverse maternal and pregnancy outcomes by increasing symptom severity and, consequently, hospital and Intensive Care Unit (ICU) admission, and, finally, death rates. For micronutrients, the results are less definite, even if there seems to be a lower level of micronutrients, in particular Vitamin D, in COVID-19-positive pregnant women.

Keywords: BMI; COVID-19; hospital admission; maternal death; micronutrients; nutritional status; obesity; pregnancy; severe COVID-19; vitamin D.

Figure A1

(A) Sensitivity analysis including small sample size studies (<100 per arm) and using a fixed effect model. BMI >= 30 vs. BMI <3 0—Disease severity [15,16,17,18,19,20,21,22]. (B) Sensitivity analysis including small sample size studies (<100 per arm) and using a fixed effect model. BMI >= 30 vs. BMI < 30—Hospital admissions [27,28,29,30,31]. (C) Sensitivity analysis including only good quality studies—Disease severity. BMI >= 30 vs. BMI < 30 –. [15,16,17,18,19,20,21,22]. (D) Sensitivity analysis including only good quality studies—Maternal death. [23,24,25,26]. (E) Sensitivity analysis including only good quality studies—Hospital admission. [27,28,29,30,31]. (F) Sensitivity analysis including only good quality studies—Vit D serum levels [32,33].

Figure A1

(A) Sensitivity analysis including small sample size studies (<100 per arm) and using a fixed effect model. BMI >= 30 vs. BMI <3 0—Disease severity [15,16,17,18,19,20,21,22]. (B) Sensitivity analysis including small sample size studies (<100 per arm) and using a fixed effect model. BMI >= 30 vs. BMI < 30—Hospital admissions [27,28,29,30,31]. (C) Sensitivity analysis including only good quality studies—Disease severity. BMI >= 30 vs. BMI < 30 –. [15,16,17,18,19,20,21,22]. (D) Sensitivity analysis including only good quality studies—Maternal death. [23,24,25,26]. (E) Sensitivity analysis including only good quality studies—Hospital admission. [27,28,29,30,31]. (F) Sensitivity analysis including only good quality studies—Vit D serum levels [32,33].

Figure A2

(A) Covid+ pregnant women vs. Covid- pregnant women, outcome: 1.1 Vitamin D serum levels. Funnel plot. (B) Funnel plot of comparison: 2 BMI >= 30 vs. BMI < 30, outcome: Disease severity. (C) Funnel plot of comparison: 2 BMI >= 30 vs. BMI < 30, outcome: Maternal death. (D) Funnel plot of comparison: 2 BMI >= 30 vs. BMI < 30, outcome: Hospital admission.

Figure A2

(A) Covid+ pregnant women vs. Covid- pregnant women, outcome: 1.1 Vitamin D serum levels. Funnel plot. (B) Funnel plot of comparison: 2 BMI >= 30 vs. BMI < 30, outcome: Disease severity. (C) Funnel plot of comparison: 2 BMI >= 30 vs. BMI < 30, outcome: Maternal death. (D) Funnel plot of comparison: 2 BMI >= 30 vs. BMI < 30, outcome: Hospital admission.

Figure A2

(A) Covid+ pregnant women vs. Covid- pregnant women, outcome: 1.1 Vitamin D serum levels. Funnel plot. (B) Funnel plot of comparison: 2 BMI >= 30 vs. BMI < 30, outcome: Disease severity. (C) Funnel plot of comparison: 2 BMI >= 30 vs. BMI < 30, outcome: Maternal death. (D) Funnel plot of comparison: 2 BMI >= 30 vs. BMI < 30, outcome: Hospital admission.

Figure 1

Flow chart for the selection of studies.

Figure 2

BMI >= 30 vs. BMI < 30—disease severity (critical/severe vs. mild) [15,16,17,18,19,20,21,22].

Figure 3

BMI >= 30 vs. BMI < 30—maternal death due to COVID-19-related causes) [23,24,25,26].

Figure 4

BMI >= 30 vs. BMI < 30—hospital admissions for COVID-19-related causes [27,28,29,30,31].

Figure 5

COVID-19-positive pregnant women vs. COVID-19-negative pregnant women—vitamin D serum levels [32,33].