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Women’s Health Library

Our Health Library information does not replace the advice of a doctor. Please be advised that this information is made available to assist our patients to learn more about their health. Our providers may not see and/or treat all topics found herein.

Rh factor

The surface of red blood cells contains markers that the immune system can recognize—one of these markers is the Rh factor (Rh [D] antigen). A person whose blood contains the Rh factor is Rh-positive (D); a person whose blood does not contain the Rh factor is Rh-negative (d).

Blood type contains information about the presence (+) or absence (–) of the Rh factor. Blood type is indicated by a letter (A, B, or O) and a symbol (+ or –). If a person has B negative (B–) blood, for example, that person is Rh-negative. A person with B positive blood (B+) is Rh-positive.

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Telehealth & COVID-19

Telehealth Visits are available. Request by calling (650) 239-5303 or  click “Request Appointment” above. We have a secure HIPAA compliant platform that allows me discuss your health matters privately. If you need an in person visit, please know we are using CDC guidelines of distancing patients and disinfecting. Masks are mandatory for all staff and patients. Dr Serrato does not see COVID patients here nor those with any respiratory symptoms. Your safety is of the utmost concern to me.… Continue Reading