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To find out what to do if you think you have symptoms, please visit Coronavirus symptom checker. Or visit our encyclopaedia page, which has general information and includes a BSL video.
NOTE: For up to date information about Coronavirus (COVID-19) visit the UK Department of Health and Social Care.
Some women's cycles are not exactly 28 days. If your cycle is shorter or longer than 28 days, please adjust the number below.