Rh Testing in Early Pregnancy

Publication Date: July 20, 2022
Last Updated: August 10, 2022


If the fetus is reasonably certain to be Rh negative, Rhogam is not needed in any circumstance or any gestational age.

Rh testing and administration are not recommended prior to 12 weeks gestation for patients undergoing spontaneous, medication, or uterine aspiration abortion.

Uterine aspiration is the standard of care for uterine evacuation and sharp curettage is not recommended. However, if sharp curettage is deemed clinically necessary, it is unclear how this might impact the need for Rh immunoglobulin.

For patients under 12 weeks gestation, although not recommended, Rh testing and Rh immunoglobulin administration may be considered at patient request as part of a shared decision-making process, discussing the patient's future fertility desires in the context of existing data.

Similarly, patients may decline recommended Rh immunoglobulin testing and administration. Common reasons for declining include, but are not limited to, no desire for future pregnancy, relative certainty that patient is Rh-positive, relative certainty that pregnancy is Rh-negative, and desire to avoid administration of human blood product. It is important to document the counseling, recommendation, and declination.

Whenever administration occurs prior to 12 weeks gestation, a 50mcg (250 IU) dose of Rh immunoglobulin should be used.

The 100-mcg dose (500IU) of Rh immunoglobulin is recommended as safe and effective at 12-18 weeks gestation. This dose may be available in international settings or can be achieved by administering two-50mcg (250IU) doses.

Continued administration of the 300mcg (1500IU) dose for patients undergoing abortion above 18 weeks gestation is prudent.

Updated SFP recommendations for Rh immunoglobulin administration of minimum dose by gestational age

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Gestational age Recommendation for Rh immunoglobulin
<12 weeks No administration recommended routinely for spontaneous or induced abortion.
50 mcg/ 250 IU for ectopic pregnancy, sharp curettage, or other invasive procedures
13 to ≤18 weeks 100-mcg/ 500 IU dose
>18 weeks 300-mcg/ 1500 IU dose

Recommendation Grading




Rh Testing in Early Pregnancy

Authoring Organization

Publication Month/Year

July 20, 2022

Last Updated Month/Year

August 14, 2023

Document Type


Country of Publication


Document Objectives

Historical evidence that fetal red blood cell (RBC) exposure during early spontaneous or induced abortion can cause maternal Rh sensitization is limited. A close reading of these studies indicates that forgoing Rh immunoglobulin administration before 12-weeks gestation is highly unlikely to increase risk of Rh (D) antibody development, and recent studies indicate that fetal RBC exposure during aspiration abortion <12 weeks gestation is below the calculated threshold to cause maternal Rh sensitization, and the amount of fetomaternal hemorrhage during dilation and evacuation procedures up to 18-weeks gestation is adequately treated with 100-mcg of Rh immunoglobulin. We provide updated recommendations for Rh immunoglobulin administration based on this new evidence.

Inclusion Criteria

Female, Adult

Health Care Settings

Ambulatory, Hospital, Laboratory services, Outpatient

Intended Users

Nurse, nurse practitioner, physician, physician assistant


Counseling, Assessment and screening

Diseases/Conditions (MeSH)

D011247 - Pregnancy, D012234 - Rho Factor


pregnancy, Pregnancy care, rh testing

Source Citation

Horvath S, Goyal V, Traxler S, Prager S. Society of Family Planning committee consensus on Rh testing in early pregnancy. Contraception. 2022 Jul 21:S0010-7824(22)00197-4. doi: 10.1016/j.contraception.2022.07.002. Epub ahead of print. PMID: 35872236.