Coronavirus infection, also known as COVID-19, has become a global pandemic with over 3 million cases and 250,000 deaths worldwide. Coronaviruses (CoV) belong to a family of viruses that predominately infect mammals and birds, affecting their lungs, intestinal tract, liver and nervous systems. Prior to the discovery of the current novel coronavirus strain (SARS-CoV-2), there were six different strains that are known to infect humans, which includes the virus that caused the severe acute respiratory syndrome (SARS) pandemic in 2002. In humans, the majority of severe illness from SARs and COVID-19 is due to inflammation of the lungs and pneumonia. Pregnancy poses a significantly increased risk of viral pneumonia and during SARS more pregnant women required intensive care and breathing support, and the proportion of deaths was higher when compared to non-pregnant adults. Furthermore, kidney failure and development of abnormal blood clotting disorders, which occurs during severe infection, is more common in pregnancy and the associated changes in blood vessels extend to the placentas of infected pregnant women, thus potentially affecting the fetus. This makes pregnant women affected by the virus at high risk of developing severe complications. Fortunately, there have been a number of biomarkers identified that are associated with illness severity. These include, specialised white blood cells, blood clotting cells and constituents, as well as other measures of heart and kidney function. We propose that these biomarkers are important correlates of clinical disease severity and prognosis in pregnant and postnatal women. This knowledge has the potential to help clinicians during this pandemic to better manage and care for their patients.

This study will be a retrospective case review using existing clinical data from participating centres. To date there have already been 18,000 confirmed cases in Greater London. Our study design will aim to include patients who were diagnosed with COVID-19 at the start of the pandemic as well as new and current cases.

The study design requires data to be extracted from National Health Service (NHS) electronic and paper notes, which will contain patient identifiable information. For confidentiality, all patient identifiable data will only be collected by members of the direct care team. This data will be encrypted and stored in a local NHS trust computer at participating sites. In order to maintain confidentiality, all data will then be anonymised before being inputted on a data collection tool and spreadsheet. Therefore, research teams will only be provided with a de-identified dataset. This data will be transferred across to the study co-ordination centre, following NHS information governance rules for data to be compiled and analysed. At the co-ordination centre, this data will be stored in an Imperial College London computer, and will only be accessible to the research team.

Inclusion Criteria:

• COVID-19 infection
• 18-50 years for Groups A and B and 18-60 years for Groups C and D
• Female for groups A and B. Both male and female for groups C and D.

Exclusion Criteria:

• Participants who have previously been part of a SARS-CoV-2 vaccine trial.
• Current hospital admission due to another respiratory disease, such as influenza.
• Obvious clinical deterioration due to another medical problem such as cardiovascular disease, diabetes or malignancy.
• Evidence of HIV infection and/or participants on anti-retroviral drug therapy.
• Participants on chemotherapy, biologics, immune-modulators or immunosuppressive drugs (not including intramuscular steroids for fetal lung maturity).

Due to the novel nature of this project, patients will not be stratified for specific demographic differences such as age, ethnicity or BMI. As there is very little data on SARS or COVID-19 infection in pregnant and postnatal women within 6 weeks of birth, power calculations used data from non-pregnant cases. In our institution so far, we have had 17 pregnant or postnatal women with COVID-19, and approximately 5 non-pregnant women of childbearing age out of a total of 273 cases (as of 1nd May 2020). Therefore, for some of non-pregnant data collection, we will be using data obtained from both male and female participants with a wider age range than our pregnant and postnatal group. Once all the data has been collected, we may stratify them based on age, gender, BMI, and ethnicity.

Research team wishes to enable any meta-analyses of COVID-19 trials making appropriate requests. No plan to share IPD has been made at this time.