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Mayo Clinic. 2016. Symptoms of pregnancy: What happens first. http://www.mayoclinic.org/healthy-lifestyle/getting-pregnant/in-depth/symptoms-of-pregnancy/art-20043853Opens a new window [Accessed November 2016]
Mayo Clinic. 2015. Home pregnancy tests: Can you trust the results? http://www.mayoclinic.org/healthy-lifestyle/getting-pregnant/in-depth/art-20047940Opens a new window [Accessed November 2016]
NIH. Undated. What are some common signs of pregnancy? National Institute of Child Health and Human Development, National Institutes of Health. https://www.nichd.nih.gov/health/topics/pregnancy/conditioninfo/pages/signs.aspxOpens a new window [Accessed November 2016]
OWH. 2014. Pregnancy tests fact sheet. U.S. Office on Women's Health. https://www.womenshealth.gov/publications/our-publications/fact-sheet/pregnancy-test.htmlOpens a new window [Accessed November 2016]
OWH. 2010. Knowing if you are pregnant. U.S. Office on Women's Health. https://www.womenshealth.gov/pregnancy/before-you-get-pregnant/knowing-if-pregnant.htmlOpens a new window [Accessed November 2016]
