It still unclear how SARS-CoV-2 affects pregnant women and their offspring, as well as which factors may influence obstetrical disease and outcomes, including the timing of maternal viral exposure by gestational age, the effects of parity, age, host immune responses, coexisting medical and obstetrical conditions and the effects of treatment regimens. While further information is gathered, based on the existing evidence from other infections causing pneumonia, pregnant women should be considered to be at high risk for developing severe infection during the current COVID-19 epidemic. Results from clinical trials with HCQ in nonpregnant adults may not be directly extrapolated to pregnant women given the special features of the pregnancy status. Thus, clinical research is urgently needed to improve the care and reduce the risk of poor pregnancy outcomes of women in this and in future epidemics.

This is a randomized, double blinded, placebo-controlled multicenter clinical trial including 714 pregnant women (200 SARS-CoV-2 infected -100 symptomatic with mild disease and 100 asymptomatic- pregnant women and 514 SARS-CoV-2 uninfected pregnant women who are contacts with a SARS-CoV-2 case) with the main objectives of assessing the safety and efficacy of oral hydroxychloroquine (HCQ) in reducing maternal viral shedding by PCR, and preventing incident SARS-CoV-2 infection and disease severity. Pregnant women undergoing antenatal follow up at five maternity hospitals, presenting at least one sign and/or one mild suggestive symptoms and a positive SARS-CoV-2 PCR test, or who are contacts of a suspected or confirmed case, will be recruited and randomized 1:1 to receive HCQ orally (400 mg/day for 3 days, followed by 200 mg/day for 11 days) or placebo. Women will be followed up for the duration of the intervention. One week after intervention completion, a SARS-CoV-2 PCR test will be repeated. At delivery, the pregnancy outcome will be registered, and a cord blood sample will be collected to measure for IgG and IgM of SARS-CoV-2. A neonatal nasopharyngeal aspirate will be collected to perform PCR SARS-CoV-2 testing.

Inclusion Criteria:

• Presenting with fever (≥37.5ºC) and/or one mild symptom suggestive of COVID-19 disease (cough, dyspnoea, chills, odynophagia, diarrhoea, muscle pain, anosmia, taste disorder, headache) OR contact of a SARS-CoV-2 confirmed or suspected case in the past 14 days
• More than 12 weeks of gestation (dated by ultrasonography)
• Agreement to deliver in the study hospitals

Exclusion Criteria:

• Known hypersensitivity to HCQ or other 4-aminoquinoline compounds
• History of retinopathy of any aetiology
• Concomitant use of digoxin, cyclosporine, cimetidine
• Known liver disease
• Clinical history of cardiac pathology including known long QT syndrome
• Unable to cooperate with the requirements of the study
• Participating in other intervention studies
• Delivery onset (characterized by painful uterine contractions and variable changes of the cervix, including some degree of effacement and slower progression of dilatation up to 5 cm for first and subsequent labours)

It would be shared at time of publication.

By the end of study