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ObjectiveTo determine the clinical manifestations, risk factors, treatment modalities and maternal outcomes in pregnant women with lab-confirmed COVID-19 and compare it with COVID-19 negative pregnant women in same age group.DesignMulticentric case-control study.Data sourcesAmbispective primary data collection through paper-based forms from 20 tertiary care centres across India between April and November 2020.Study populationAll pregnant women reporting to the centres with a lab-confirmed COVID-19 positive result matched with controls.Data qualityDedicated research officers extracted hospital records, using modified WHO Case Record Forms (CRF) and verified for completeness and accuracy.Statistical analysisData converted to excel files and statistical analyses done using STATA 16 (StataCorp, TX, USA). Odds ratios (ORs) with 95% confidence intervals (CI) estimated using unconditional logistic regression.ResultsA total of 76,264 women delivered across 20 centres during the study period. Data of 3723 COVID positive pregnant women and 3744 age-matched controls was analyzed. Of the positive cases 56·9% were asymptomatic. Antenatal complications like preeclampsia and abruptio placentae were seen more among the cases. Induction and caesarean delivery rates were also higher among Covid positive women. Pre-existing maternal co-morbidities increased need for supportive care. There were 34 maternal deaths out of the 3723(0.9%) positive mothers, while covid negative deaths reported from all the centres were 449 of 72,541 (0·6%).ConclusionCovid-19 infection predisposed to adverse maternal outcomes in a large cohort of Covid positive pregnant women as compared to the negative controls.