U.S. Department of Health and Human Services

Rh Incompatibility

Rh Factor

If you're not sure what your Rh factor is and think you're pregnant, it's important to start regular prenatal care as soon as possible — including blood-type testing. Your Rh factor may play a role in your baby's health, so it's important to know this information early in your pregnancy.

Review Date: Monday, August 13, 2012

American Academy of Family Physicians

Rh Incompatibility

Be sure to have a blood-type test to determine your Rh factor when you become pregnant. This article explains why.

Review Date: Wednesday, February 22, 2012

The Nemours Foundation

The RH Factor: How It Can Affect Your Pregnancy- (PDF)

This article provides a brief overview of RH Immunoglobulin (RhIg), and its role in preventing anemia and more serious problems in the babies of RH-negative mothers.

Review Date: Thursday, December 18, 2014

American Congress of Obstetricians and Gynecologists

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