Coronavirus Disease 2019 (COVID-19) During Pregnancy: Prevalence of Seroconversion, Effect on Maternal and Perinatal Outcomes and Risk of Vertical Transmission (COVID-MAP)

The objectives of this proposal are to: 1) determine the rate of SARS-CoV-2 seroconversion in unselected pregnant women in Hong Kong; 2) determine the rate of SARS-CoV-2 infection in women presenting with miscarriage and stillbirth; 3) follow the pregnancy course and perinatal outcome of confirmed COVID-19-infected pregnant cases; 4) determine the risk and characteristics of vertical transmission; and 5) evaluate the placental barrier, immune response and fetal damage in vertical transmission of SARS-CoV-2. A series of longitudinal and cross-sectional observational studies, and a laboratory-based study will be conducted to fulfil the 5 objectives.

With over 10 million individuals infected worldwide, the coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a global public health crisis. It is recognized that pregnant women are at an increased risk of acquiring viral respiratory infection and developing severe pneumonia due to the physiologic changes in their immune and cardiopulmonary systems. Previous studies have attempted to determine maternal and perinatal outcome and potential risk of vertical transmission in pregnant women affected by COVID-19, however, relevant clinical data and biological samples have not been collected in a systematic manner. The research project will engage in collaborative research across obstetricians/maternal-fetal medicine subspecialists, gynecologist, infectious disease specialists, pediatrician, developmental and molecular biologists and bioinformatician between the CUHK, China and Spain. The objectives of this proposal are to: 1) determine the rate of SARS-CoV-2 seroconversion in unselected pregnant women in Hong Kong; 2) determine the rate of SARS-CoV-2 infection in women presenting with miscarriage and stillbirth; 3) follow the pregnancy course and perinatal outcome of confirmed COVID-19-infected pregnant cases; 4) determine the risk and characteristics of vertical transmission; and 5) evaluate the placental barrier, immune response and fetal damage in vertical transmission of SARS-CoV-2. A series of longitudinal and cross-sectional observational studies, and a laboratory-based study will be conducted to fulfil the 5 objectives.

Results generated will inform obstetrics and gynecology, pediatric and infectious disease scientific communities as well as public health specialists and policy makers regarding: (1) the estimated seroconversion rate in women of childbearing age; these results will help (i) improve the approach to care for pregnancy and childbirth during the COVID-19 outbreak; and (ii) formulate preventive measures to be implemented specifically for pregnant women in reducing risk of infection and associated complications to both the women and their unborn child; (2) the impact of COVID-19 on maternal and perinatal outcomes; data from high-quality research will inform practice during the COVID-19 outbreak, guiding healthcare professionals on how to adjust the management approach to infected pregnant women and the exact risks the infection poses to the babies; (3) the risk of vertical transmission at different stages of pregnancy and its sequelae; findings of this study will guide counselling, decision making and clinical management; (4) the identification of cellular site of viral entry and replication in the maternal-fetal interface that would be instrumental in designing therapeutic measures to cease vertical transmission and developing therapeutic treatments.

Eligibility Criteria:
Objective 1: Seroconversion during pregnancy

Inclusion criteria:

* Pregnant women who attended for Down syndrome screening (DSS) at 11-13 weeks
* Had serum sample taken between 1 November 2019 and 1 June 2020 consented for stored serum for future research
* Intended to deliver at the booking hospital.

Objective 2: SARS-CoV-2 and pregnancy loss

Inclusion criteria:

•Pregnant women presenting with first and second trimester miscarriage in Hong Kong and Spain, as well as those with stillbirth during periods of 6 and 12 months, respectively.

Objective 3: Pregnancy course and perinatal outcome

Inclusion criteria:

•Pregnant women affected by COVID-19

Objective 4: Vertical transmission

Inclusion criteria:

•Pregnant women affected by COVID-19

Objective 5: Potential mechanisms for vertical transmission

Inclusion criteria:

•Pregnant women affected by COVID-19