• U.S. Preventive Services Task Force (USPSTF). Screening for Rh(D) incompatibility: recommendation statement. Rockville (MD): Agency for Healthcare Research and Quality (AHRQ); 2004 Feb. 4 p. [3 references]

This is the current release of the guideline.

This release updates a previously published guideline: U.S. Preventive Services Task Force. Guide to clinical preventive services. 2nd ed. Baltimore (MD): Williams & Wilkins; 1996. Chapter 38, Screening for D (Rh) incompatibility. p. 425-432.

Rh(D) incompatibility

Prevention
Screening

Family Practice
Internal Medicine
Obstetrics and Gynecology
Preventive Medicine

Advanced Practice Nurses
Allied Health Personnel
Nurses
Physician Assistants
Physicians

• To summarize the current U.S. Preventive Services Task Force (USPSTF) recommendations for the screening for Rh(D) incompatibility and the supporting scientific evidence
• To update the 1996 recommendations contained in the Guide to Clinical Preventive Services, Second Edition

Pregnant women seen in primary care settings

1. Screening for Rh(D) incompatibility using Rh(D) blood typing and antibody testing
2. Repeated Rh(D) antibody testing as indicated

Interventions considered but not specifically recommended:

Rh(D) immunoglobulin as appropriate

Key Question 1: Is there new, direct evidence that screening for Rh(D) incompatibility leads to reduced maternal morbidity or mortality?

Key Question 2: Have new screening tests been developed and tested to show improvement in the health outcomes of Rh(D) incompatibility?

Key Question 3: Have new treatment protocols been developed and tested to show improvement in health outcomes of Rh(D) incompatibility?

Key Questions 4 and 5: Have new harms been identified for screening or treatment of Rh(D) incompatibility and/or has stronger evidence for existing harms become apparent?

Hand-searches of Published Literature (Primary Sources)
Searches of Electronic Databases

A general search strategy, limited to the English language and the years 1994 to 2002, was used to search MEDLINE®. Because no clearly defined Medical Subject Headings® (MeSH®) were relevant to this topic, the search strategy focused on a series of key terms. The following key terms yielded 1,154 articles: Rh (D) Immune Globulin, Rh-Hr Blood-Group System, Erythroblastosis, and Fetal, Rh Isoimmunization.

This general search strategy was refined into a combined search strategy linking Rh(D) incompatibility with screening (29 records), meta-analyses (1 record), reviews (132 records), randomized controlled trials (RCTs) (14 records), outcomes (37 records), and editorials (20 records) for review. The search strategy was expanded in response to expert reviews to include amniocentesis and fetal antigen as well as fetal anemia detection.

Citations were analyzed and abstracts that fit the eligibility criteria for assessment were culled. Full text articles based on potentially suitable abstracts were obtained and reviewed for inclusion or exclusion.

Key Question 1 = 0 studies
Key Question 2 = 2 studies
Key Question 3 = 0 studies
Key Questions 4 and 5 = 0 studies

Weighting According to a Rating Scheme (Scheme Given)

The U.S. Preventive Services Task Force (USPSTF) grades the quality of the overall evidence for a service on a 3-point scale (good, fair, poor):

Good

Evidence includes consistent results from well-designed, well-conducted studies in representative populations that directly assess effects on health outcomes.

Fair

Evidence is sufficient to determine effects on health outcomes, but the strength of the evidence is limited by the number, quality, or consistency of the individual studies, generalizability to routine practice, or indirect nature of the evidence on health outcomes.

Poor

Evidence is insufficient to assess the effects on health outcomes because of limited number or power of studies, important flaws in their design or conduct, gaps in the chain of evidence, or lack of information on important health outcomes.

Systematic Review

Not stated

Balance Sheets
Expert Consensus

When the overall quality of the evidence is judged to be good or fair, the U.S. Preventive Services Task Force (USPSTF) proceeds to consider the magnitude of net benefit to be expected from implementation of the preventive service. Determining net benefit requires assessing both the magnitude of benefits and the magnitude of harms and weighing the two.

The USPSTF classifies benefits, harms, and net benefits on a 4-point scale: "substantial," "moderate," "small," and "zero/negative."

"Outcomes tables" (similar to "balance sheets") are the USPSTF's standard resource for estimating the magnitude of benefit. These tables, prepared by the topic teams for use at USPSTF meetings, compare the condition specific outcomes expected for a hypothetical primary care population with and without use of the preventive service. These comparisons may be extended to consider only people of specified age or risk groups or other aspects of implementation. Thus, outcomes tables allow the USPSTF to examine directly how the preventive service affects benefits for various groups.

When evidence on harms is available, the topic teams assess its quality in a manner like that for benefits and include adverse events in the outcomes tables. When few harms data are available, the USPSTF does not assume that harms are small or nonexistent. It recognizes a responsibility to consider which harms are likely and judge their potential frequency and the severity that might ensue from implementing the service. It uses whatever evidence exists to construct a general confidence interval on the 4-point scale (e.g., substantial, moderate, small, and zero/negative).

Value judgments are involved in using the information in an outcomes table to rate either benefits or harms on the USPSTF's 4-point scale. Value judgments are also needed to weigh benefits against harms to arrive at a rating of net benefit.

In making its determinations of net benefit, the USPSTF strives to consider what it believes are the general values of most people. It does this with greater confidence for certain outcomes (e.g., death) about which there is little disagreement about undesirability, but it recognizes that the degree of risk people are willing to accept to avert other outcomes (e.g., cataracts) can vary considerably. When the USPSTF perceives that preferences among individuals vary greatly, and that these variations are sufficient to make a trade-off of benefits and harms a "close-call," then it will often assign a C recommendation (see the "Recommendation Rating Scheme" field). This recommendation indicates the decision is likely to be sensitive to individual patient preferences.

The USPSTF uses its assessment of the evidence and magnitude of net benefit to make recommendations. The general principles the USPSTF follows in making recommendations are outlined in Table 5 of the companion document cited below. The USPSTF liaisons on the topic team compose the first drafts of the recommendations and rationale statements, which the full panel then reviews and edits. Recommendations are based on formal voting procedures that include explicit rules for determining the views of the majority.

From: Harris RP, Helfand M, Woolf SH, Lohr KN, Mulrow, CD, Teutsch SM, Atkins D. Current methods of the U.S. Preventive Services Task Force: a review of the process. Methods Work Group, Third U.S. Preventive Services Task Force. Am J Prev Med 2001 Apr;20(3S):21-35.

The U.S. Preventive Services Task Force (USPSTF) grades its recommendations according to one of five classifications (A, B, C, D, I) reflecting the strength of evidence and magnitude of net benefit (benefits minus harms):

A

The USPSTF strongly recommends that clinicians provide [the service] to eligible patients. The USPSTF found good evidence that [the service] improves important health outcomes and concludes that benefits substantially outweigh harms.

B

The USPSTF recommends that clinicians provide [the service] to eligible patients. The USPSTF found at least fair evidence that [the service] improves important health outcomes and concludes that benefits outweigh harms.

C

The USPSTF makes no recommendation for or against routine provision of [the service]. The USPSTF found at least fair evidence that [the service] can improve health outcomes but concludes that the balance of benefits and harms is too close to justify a general recommendation.

D

The USPSTF recommends against routinely providing [the service] to asymptomatic patients. The USPSTF found at least fair evidence that [the service] is ineffective or that harms outweigh benefits.

I

The USPSTF concludes that the evidence is insufficient to recommend for or against routinely providing [the service]. Evidence that [the service] is effective is lacking, of poor quality, or conflicting and the balance of benefits and harms cannot be determined.

A formal cost analysis was not performed and published cost analyses were not reviewed.

Comparison with Guidelines from Other Groups
External Peer Review
Internal Peer Review

Peer Review. Before the U.S. Preventive Services Task Force (USPSTF) makes its final determinations about recommendations on a given preventive service, the Evidence-based Practice Center (EPC) and the Agency for Healthcare Research and Quality (AHRQ) send a draft systematic evidence review to 4 to 6 external experts and to federal agencies and professional and disease-based health organizations with interests in the topic. They ask the experts to examine the review critically for accuracy and completeness and to respond to a series of specific questions about the document. After assembling these external review comments and documenting the proposed response to key comments, the topic team presents this information to the Task Force in memo form. In this way, the Task Force can consider these external comments and a final version of the systematic review before it votes on its recommendations about the service. Draft recommendations are then circulated for comment from reviewers representing professional societies, voluntary organizations, and federal agencies. These comments are discussed before the whole U.S. Preventive Services Task Force before final recommendations are confirmed.

Recommendations of Others. Recommendations regarding screening for Rh(D) incompatibility were considered from the following groups: the Canadian Task Force on Preventative Health Care and the American College of Obstetricians and Gynecologists.

The U.S. Preventive Services Task Force (USPSTF) grades its recommendations (A, B, C, D, or I) and the quality of the overall evidence for a service (good, fair, poor). The definitions of these grades can be found at the end of the "Major Recommendations" field.

The U.S. Preventive Services Task Force (USPSTF) strongly recommends Rh(D) blood typing and antibody testing for all pregnant women during their first visit for pregnancy-related care. A Recommendation.

The USPSTF found good evidence that Rh(D) blood typing, anti-Rh(D) antibody testing, and intervention with Rh(D) immunoglobulin, as appropriate, prevents maternal sensitization and improves outcomes for newborns. The benefits substantially outweigh any potential harms.

The USPSTF recommends repeated Rh(D) antibody testing for all unsensitized Rh(D)-negative women at 24 to 28 weeks' gestation, unless the biological father is known to be Rh (D)-negative. B Recommendation.

The USPSTF found fair evidence that repeated antibody testing for unsensitized Rh(D)-negative women (unless the father is also known to be Rh[D]-negative) and intervention with Rh(D) immunoglobulin, as appropriate, provides additional benefit over a single test at the first prenatal visit in preventing maternal sensitization and improving outcomes for newborns. The benefits of repeated testing substantially outweigh any potential harms.

The USPSTF found no new evidence addressing the role of screening, new screening tests, new treatment protocols, or potential harms associated with screening and treatment of Rh(D) incompatibility. However, there is pre-existing good evidence for the efficacy and effectiveness of blood typing, anti-Rh(D) antibody screening, and postpartum Rh(D) immunoglobulin prophylaxis.

Clinical Considerations

• Administration of a full (300 micrograms) dose of Rh(D) immunoglobulin is recommended for all unsensitized Rh(D)-negative women after repeated antibody testing at 24 to 28 weeks' gestation.
• If an Rh(D)-positive or weakly Rh(D)-positive (e.g., D^u-positive) infant is delivered, a dose of Rh(D) immunoglobulin should be repeated postpartum, preferably within 72 hours after delivery. Administering Rh(D) immunoglobulin at other intervals after delivery has not been studied.
• Unless the biological father is known to be Rh(D)-negative, a full dose of Rh(D) immunoglobulin is recommended for all unsensitized Rh(D)-negative women after amniocentesis and after induced or spontaneous abortion; however, if the pregnancy is less than 13 weeks, a 50 microgram dose is sufficient.
• The benefit of routine administration of Rh(D) immunoglobulin after other obstetric procedures or complications such as chorionic villus sampling, ectopic pregnancy termination, cordocentesis, fetal surgery or manipulation (including external version), antepartum placental hemorrhage, abdominal trauma, antepartum fetal death, or stillbirth is uncertain due to inadequate evidence.

Definitions:

Strength of Recommendations

The USPSTF grades its recommendations according to one of five classifications (A, B, C, D, I) reflecting the strength of evidence and magnitude of net benefit (benefits minus harms):

A

The USPSTF strongly recommends that clinicians provide [the service] to eligible patients. The USPSTF found good evidence that [the service] improves important health outcomes and concludes that benefits substantially outweigh harms.

B

The USPSTF recommends that clinicians provide [the service] to eligible patients. The USPSTF found at least fair evidence that [the service] improves important health outcomes and concludes that benefits outweigh harms.

C

The USPSTF makes no recommendation for or against routine provision of [the service]. The USPSTF found at least fair evidence that [the service] can improve health outcomes but concludes that the balance of benefits and harms is too close to justify a general recommendation.

D

The USPSTF recommends against routinely providing [the service] to asymptomatic patients. The USPSTF found at least fair evidence that [the service] is ineffective or that harms outweigh benefits.

I

The USPSTF concludes that the evidence is insufficient to recommend for or against routinely providing [the service]. Evidence that [the service] is effective is lacking, of poor quality, or conflicting and the balance of benefits and harms cannot be determined.

Strength of Evidence

The USPSTF grades the quality of the overall evidence for a service on a 3-point scale (good, fair, poor):

Good

Evidence includes consistent results from well-designed, well-conducted studies in representative populations that directly assess effects on health outcomes.

Fair

Evidence is sufficient to determine effects on health outcomes, but the strength of the evidence is limited by the number, quality, or consistency of the individual studies, generalizability to routine practice, or indirect nature of the evidence on health outcomes.

Poor

Evidence is insufficient to assess the effects on health outcomes because of limited number or power of studies, important flaws in their design or conduct, gaps in the chain of evidence, or lack of information on important health outcomes.

None provided

The type of evidence supporting the recommendations is identified in the "Major Recommendations" field.

• The U.S. Preventive Services Task Force (USPSTF) found good evidence that Rh(D) blood typing, anti-Rh(D) antibody testing, and intervention with Rh(D) immunoglobulin, as appropriate, prevents maternal sensitization and improves outcomes for newborns. The benefits substantially outweigh any potential harms.
• The USPSTF found fair evidence that repeated antibody testing for unsensitized Rh(D)-negative women (unless the father is also known to be Rh[D]-negative) and intervention with Rh(D) immunoglobulin, as appropriate, provides additional benefit over a single test at the first prenatal visit in preventing maternal sensitization and improving outcomes for newborns. The benefits of repeated testing substantially outweigh any potential harms.

Not stated

The U.S. Preventive Services Task Force recommendations are independent of the U.S. government. They should not be construed as an official position of Agency for Healthcare Research and Quality (AHRQ) or the U.S. Department of Health and Human Services.

Staying Healthy

Effectiveness
Patient-centeredness

• U.S. Preventive Services Task Force (USPSTF). Screening for Rh(D) incompatibility: recommendation statement. Rockville (MD): Agency for Healthcare Research and Quality (AHRQ); 2004 Feb. 4 p. [3 references]

Not applicable: The guideline was not adapted from another source.

2004 Feb 24

United States Preventive Services Task Force - Independent Expert Panel

The U.S. Preventive Services Task Force (USPSTF) is a federally-appointed panel of independent experts. Conclusions of the U.S. Preventive Services Task Force do not necessarily reflect policy of the U.S. Department of Health and Human Services (DHHS) or its agencies.

United States Government

U.S. Preventive Services Task Force (USPSTF)

The U.S. Preventive Services Task Force (USPSTF) has an explicit policy concerning conflict of interest. All members and Evidence-based Practice Center (EPC) staff disclose at each meeting if they have an important financial conflict for each topic being discussed. Task Force members and EPC staff with conflicts can participate in discussions about evidence, but members abstain from voting on recommendations about the topic in question.

From: Harris RP, Helfand M, Woolf SH, Lohr KN, Mulrow, CD, Teutsch SM, Atkins D. Current methods of the U.S. Preventive Services Task Force: a review of the process. Methods Work Group, Third U.S. Preventive Services Task Force. Am J Prev Med 2001 Apr;20(3S):21-35.

This is the current release of the guideline.

This release updates a previously published guideline: U.S. Preventive Services Task Force. Guide to clinical preventive services. 2nd ed. Baltimore (MD): Williams & Wilkins; 1996. Chapter 38, Screening for D (Rh) incompatibility. p. 425-432.

This summary was completed by ECRI on June 30, 1998. The information was verified by the guideline developers on December 1, 1998. This summary was updated by ECRI on April 8, 2004. The updated information was verified by the guideline developer on April 22, 2004.