Rh factor
Abbreviation: Rh
The Rh factor is a protein found on the surface of red blood cells. If you have it, you are Rh positive. If you do not, you are Rh negative. This matters in pregnancy because if an Rh-negative mother carries an Rh-positive baby, small amounts of the baby's blood can cross into the mother's bloodstream. Her immune system may then produce antibodies against Rh-positive blood. These antibodies are harmless in a first pregnancy but can attack the red blood cells of future Rh-positive babies, causing a condition called hemolytic disease of the newborn. A simple blood test at your first antenatal visit determines your Rh status.
What This Means for You
Understanding Rh factor is an important part of your pregnancy journey. During pregnancy, your care team will use this term regularly. Being familiar with it means you can ask better questions and feel more confident at your antenatal appointments.
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All pregnant women in Singapore are routinely tested for Rh factor at their first booking visit at KKH, NUH, or a private clinic. If you are Rh negative, your doctor will discuss a prevention plan with you early in pregnancy.
Related Terms
Source: https://www.acog.org/womens-health/dictionary
Always consult your healthcare provider for personalised advice.
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