The Incidence Rate of COVID-19 and its Relationship with Maternal and Neonatal Outcomes among Pregnant Women during Iran’s First and Second Waves: A Multicenter Cohort Study in Tehran

Background aim: COVID-19 infection may adversely affect pregnancy outcomes. We aimed to assess the incidence rate of the COVID-19 virus and its effect on maternaland neonatal outcomes. Methods: This was a cohort study in which a number of health-care centers in Tehran province were randomly selected, and all pregnant women referring to these centers were screened for COVID-19 from April 2020 to July 2020. Out of 15520 pregnant women, 263 individuals infected with COVID-19, who were followed until delivery. To collect the data, a demographic and obstetric characteristics questionnaire and a maternal and neonatal outcome checklist were used. Data analysis was done by SPSS version 22 using the Chi-square test, independent t-test, and logistic regression model. Results: The incidence of COVID-19 among participants was 17 per 1000 (95% CI: 15-19). Women with a higher BMI (OR = 1.198, CI =1.003-1.431, P = 0.047) and lower blood oxygen level (OR= 0.886, CI: 0.808-.970, P=.009) were more likely to have adverse pregnancy outcomes. Preterm labor (18.3%) was the most common outcome of pregnancy, followed by stillbirth (0.8%), ICU admission (3.0%), maternal mortality (1.1%), need to mechanical ventilation (1.5%) and preeclampsia 1(0.38). Regarding neonatal outcomes, neonatal COVID-19 was seen in 1.9% of cases, NICU admission in 15.2%. Neonatal mortality without COVID-19 in 2.3%.  The majority of neonates with complications were male (29.1% vs. 21.5%, (P= 0.002). Conclusion: Pregnant women had a lower COVID-19 incidence rate than the general population, but when infected, they were at risk for poor maternal and neonatal outcomes.