You are presented with a paragraph from a COVID-19 literature. Classify the topics of this piece of text by choosing from the following categories:

- Epidemic Forecasting: The content relates to predictions about the spread of COVID-19.
- Treatment: The paragraph discusses therapeutic methods or medication for COVID-19.
- Prevention: The content covers measures to prevent the spread of COVID-19.
- Mechanism: The paragraph explains the biological mechanisms of the virus.
- Case Report: The content is a report of a COVID-19 case.
- Transmission: The paragraph discusses how COVID-19 is transmitted.
- Diagnosis: The content is about diagnosing COVID-19 in individuals.

Your classification should be provided as an element within a JSON array. The array should be formatted with topics enclosed in double quotes and separated by commas, following the JSON format, for example: ["Topic1", "Topic2", ...]. Include all applicable topics within the array. Your output should be a valid JSON array, and no additional text should be included in your response.

Article:

BACKGROUND: During public health emergencies, including the COVID-19 pandemic, access to adequate healthcare is crucial for providing for the health and wellbeing of families. Pregnant and postpartum people are a particularly vulnerable subgroup to consider when studying healthcare access. Not only are perinatal people likely at higher risk for illness, mortality, and morbidity from COVID-19 infection, they are also at higher risk for negative outcomes due to delayed or inadequate access to routine care. METHODS: We surveyed 820 pregnant people in California over two waves of the COVID-19 pandemic: (1) a 'non-surge' wave (June 2020, n = 433), and (2) during a 'surge' in cases (December 2020, n = 387) to describe current access to perinatal healthcare, as well as concerns and decision-making regarding childbirth, over time. We also examined whether existing structural vulnerabilities - including acute financial insecurity and racial/ethnic minoritization - are associated with access, concerns, and decision-making over these two waves. RESULTS: Pregnant Californians generally enjoyed more access to, and fewer concerns about, perinatal healthcare during the winter of 2020-2021, despite surging COVID-19 cases and hospitalizations, as compared to those surveyed during the COVID-19 'lull' in the summer of 2020. However, across 'surge' and 'non-surge' pandemic circumstances, marginalized pregnant people continued to fare worse - especially those facing acute financial difficulty, and racially minoritized individuals identifying as Black or Indigenous. CONCLUSIONS: It is important for clinicians, researchers, and policymakers to understand whether and how shifting community transmission and infection rates may impact access to perinatal healthcare. Targeting minoritized and financially insecure communities for increased upstream perinatal healthcare supports are promising avenues to blunt the negative impacts of the COVID-19 pandemic on pregnant people in California.
["Prevention"]