Demonstration of Rh antigens in a 38-day-old fetus

Management of Red Cell Alloimmunization in Pregnancy

Rhesus immune globulin has resulted in a marked decrease in the prevalence of RhD alloimmunization in pregnancy; however, antibody formation to other red cell antigens continues to occur. Evaluation for the presence of anti-red cell antibodies should be routinely undertaken at the first prenatal visit. If anti-red cell antibodies are detected, consideration of a consultation or referral to a maternal-fetal medicine specialist with experience in the monitoring and treatment of these patients is warranted. Cell-free DNA can be used to determine fetal red cell antigen status to determine whether the pregnancy is at risk of complications from the red cell antibodies. First-time sensitized pregnancies are followed up with serial maternal titers, and, when indicated, serial Doppler assessment of the peak systolic velocity in the middle cerebral artery should be initiated by 16 weeks of gestation. When there is a history of an affected fetus or neonate, maternal titers are less predictive of fetal risk; if the fetus is antigen positive, serial peak systolic velocity in the middle cerebral artery measurements should be initiated by 15 weeks of gestation because intraperitoneal intrauterine blood transfusions can be used at this gestation if needed. The mainstay of fetal therapy involves intrauterine transfusion through ultrasound-directed puncture of the umbilical cord with the direct intravascular injection of red cells. A perinatal survival rate exceeding 95% can be expected at experienced centers. Neonatal phototherapy and "top-up" transfusions attributable to suppressed reticulocytosis often are still required for therapy after delivery.

[Prevention of Rh D alloimmunization in the first trimester of the pregnancy: French College of Obstetricians and Gynecologists guidelines for clinical practice]

OBJECTIVE

To provide recommendations for the prevention of Rh D alloimmunization in the first trimester of pregnancy.

MATERIALS AND METHODS

The quality of evidence of the literature was assessed following the GRADE methodology with questions formulated in the PICO format (Patients, Intervention, Comparison, Outcome) and outcomes defined a priori and classified according to their importance. An extensive bibliographic search was performed on Pubmed, Cochrane, EMBASE, and Google Scholar databases. The quality of evidence was assessed (high, moderate, low, very low) and a recommendation was formulated: (i) strong, (ii) weak, or (iii) no recommendation. The recommendations were reviewed in two rounds with reviewers from the scientific board of the French College of the OB/GYN (Delphi survey) to select the consensus recommendations.

RESULTS

The three recommendations from PICO questions reached agreement using the Delphi method. It is recommended not to administer Rh D immunoglobulin before 12 weeks of gestation to reduce the risk of alloimmunization in case of abortion or miscarriage, in RhD negative patients when the genitor is RhD positive or unknown (Weak recommendation. Very low-quality evidence). It is recommended not to administer Rh D immunoglobulin before 12 weeks of gestation to reduce the risk of alloimmunization in cases of bleeding in an ongoing intrauterine pregnancy (Weak recommendation. Very low-quality evidence). The literature data are insufficient in quality and quantity to determine if the injection of Rh D immunoglobulin reduces the risk of alloimmunization in the case of an ectopic pregnancy (No recommendation. Very low-quality evidence).

CONCLUSION

Even though the quality of evidence from the studies is very low, it is recommended not to administer Rh D immunoglobulin in case of abortion, miscarriage or bleeding before 12 weeks of amenorrhea. The quality of evidence was too low to issue a recommendation regarding ectopic pregnancy.

Guideline No. 448: Prevention of Rh D Alloimmunization

OBJECTIVE

This guideline provides recommendations for the prevention of Rh D alloimmunization (isoimmunization) in pregnancy, including parental testing, routine postpartum and antepartum prophylaxis, and other clinical indications for prophylaxis. Prevention of red cell alloimmunization in pregnancy with atypical antigens (other than the D antigen), for which immunoprophylaxis is not currently available, is not addressed in this guideline.

TARGET POPULATION

All Rh D-negative pregnant individuals at risk for Rh D alloimmunization due to potential exposure to a paternally derived fetal Rh D antigen.

OUTCOMES

Routine postpartum and antepartum Rh D immunoprophylaxis reduces the risk of Rh D alloimmunization at 6 months postpartum and in a subsequent pregnancy.

BENEFITS, HARMS, AND COSTS

This guideline details the population of pregnant individuals who may benefit from Rho(D) immune globulin (RhIG) immunoprophylaxis. Thus, those for whom the intervention is not required may avoid adverse effects, while those who are at risk of alloimmunization may mitigate this risk for themselves and/or their fetus.

EVIDENCE

For recommendations regarding use of RhIG, Medline and Medline in Process via Ovid and Embase Classic + Embase via Ovid were searched using both the trials and observational studies search strategies with study design filters. For trials, the Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and Database of Abstracts of Reviews of Effects via Ovid were also searched. All databases were searched from January 2000 to November 26, 2019. Studies published before 2000 were captured from the grey literature of national obstetrics and gynaecology specialty societies, luminary specialty journals, and bibliographic searching. A formal process for the systematic review was undertaken for this update, as described in the systematic review manuscript published separately.

VALIDATION METHODS

The authors rated the quality of evidence and strength of recommendations using the SOGC's modified GRADE approach. See Appendix A (Tables A1 for definitions and A2 for interpretations of strong and conditional [weak] recommendations).

INTENDED AUDIENCE

The intended users of this guideline include prenatal care providers such as obstetricians, midwives, family physicians, emergency room physicians, and residents, as well as registered nurses and nurse practitioners.

TWEETABLE ABSTRACT

An updated Canadian guideline for prevention of Rh D alloimmunization addresses D variants, cffDNA for fetal Rh type, and updates recommendations on timing of RhIG administration.

SUMMARY STATEMENTS

RECOMMENDATIONS.

Rh(D) immune globulin administration in pregnancy: Retrospective audit of patient safety events followed by targeted educational intervention with Bayesian analysis

OBJECTIVES

To examine local patient safety events related to the administration of anti-Rh(D) immune globin (RhIG) during pregnancy, and to follow-up with targeted educational intervention to improve knowledge of this process.

BACKGROUND

Administration RhIG is established treatment for the prevention of haemolytic disease of the foetus and newborn (HDFN). However, patient safety events in relation to its correct use continue to occur.

METHODS

A retrospective audit of patient safety events related to RhIG administration during pregnancy was performed. Targeted educational intervention in the form of PowerPoint® presentation were given to nursing staff, laboratory staff and physicians and evaluated with pre- and post-tests using multiple-choice questions given immediately before and after the presentation.

RESULTS

An annual incidence of 0.24% of patient safety events related to the administration of RhIG during pregnancy was found. These events were mostly in the preanalytical phase, for example mislabelled samples or samples for D-rosette/Kleihauer-Betke testing drawn from the baby, not the mother. Using Bayesian analysis, the probability of positive effect for the targeted educational intervention was 100% with a median improved score of 29%. This was compared with a control group using standard curriculum education intervention based on the current curriculum for nursing, laboratory and medical students which showed a median improved score of only 4.4%.

CONCLUSIONS

Administration of RhIG during pregnancy is a multistep process involving health care professionals of several disciplines providing opportunities to enhance the curriculum for nursing, laboratory and medical students and to ensure on-going education.

Risk factors for RhD immunisation in a high coverage prevention programme of antenatal and postnatal RhIg: a nationwide cohort study

OBJECTIVE

To evaluate which risk factors for RhD immunisation remain, despite adequate routine antenatal and postnatal RhIg prophylaxis (1000 IU RhIg) and additional administration of RhIg. The second objective was assessment of the current prevalence of RhD immunisations.

DESIGN

Prospective cohort study.

SETTING

The Netherlands.

POPULATION

Two-year nationwide cohort of alloimmunised RhD-negative women.

METHODS

RhD-negative women in their first RhD immunised pregnancy were included for risk factor analysis. We compared risk factors for RhD immunisation, occurring either in the previous non-immunised pregnancy or in the index pregnancy, with national population data derived from the Dutch perinatal registration (Perined).

RESULTS

In the 2-year cohort, data from 193 women were eligible for analysis. Significant risk factors in women previously experiencing a pregnancy of an RhD-positive child (n = 113) were: caesarean section (CS) (OR 1.7, 95% CI 1.1-2.6), perinatal death (OR 3.5, 95% CI 1.1-10.9), gestational age >42 weeks (OR 6.1, 95% CI 2.2-16.6), postnatal bleeding (>1000 ml) (OR 2.0, 95% CI 1.1-3.6), manual removal of the placenta (MRP) (OR 4.3, 95% CI 2.0-9.3); these factors often occurred in combination. The miscarriage rate was significantly higher than in the Dutch population (35% versus 12.-5%, P < 0.001).

CONCLUSION

Complicated deliveries, including cases of major bleeding and surgical interventions (CS, MRP), must be recognised as a risk factor, requiring estimation of fetomaternal haemorrhage volume and adjustment of RhIg dosing. The higher miscarriage rate suggests that existing RhIg protocols need adjustment or better compliance.

"Provoked" feto-maternal hemorrhage may represent insensible cell exchange in pregnancies from 6 to 22 weeks gestational age

OBJECTIVE

To quantify spontaneous and provoked fetal to maternal cell exchange in the first half of pregnancy. Transfer of fetal red blood cells (FRBCs) into the maternal circulation during the first half of pregnancy is poorly characterized but of clinical relevance for miscarriage management and invasive procedures.

STUDY DESIGN

Prospective, descriptive cohort study of women presenting for surgical termination of pregnancy with sonographically confirmed gestational age (GA). Pre-procedural and post-procedural blood samples were collected to characterize both spontaneous (pre) and provoked (post) cell exchange with analysis via flow cytometry to quantify FRBC count.

RESULTS

A total of 100 patients at 6-22 weeks GA contributed 200 matched pre- and post-procedural samples. FRBCs were identified in 69 patients including 4 who exhibited FRBCs pre-procedure only and 9 post-procedure only, for a total of 65 patients having post-procedural FRBCs. Of patients with FRBCs following their procedure, the majority (n=56, 86%) also exhibited evidence of cells before the procedure with just 9 patients (14%) exhibiting FRBCs only after. No dose-response relationship was appreciable between GA and FRBC count.

CONCLUSION

After experiencing disruption of the placenta with instrumentation, roughly two thirds of patients had detectable FRBCs in maternal circulation following their procedure but-among those that did-the majority also exhibited cell presence prior to the procedure. This leads to further questions regarding the relationship between risk events and alloimmunization potential in previable pregnancies as the rate of spontaneous transplacental cell exchange may be underappreciated and the magnitude of provoked transfer may be overestimated.

IMPLICATIONS

The relationship between feto-maternal hemorrhage risk events and alloimmunization potential in previable pregnancies has previously been poorly characterized but these data reveal spontaneous transplacental cell exchange may be underappreciated and the magnitude of provoked transfer may be overestimated.

Can we safely stop testing for Rh status and immunizing Rh-negative women having early abortions? A comparison of Rh alloimmunization in Canada and the Netherlands

Objective

The objective of this study was to compare Rh alloimmunization rates in two countries (Canada and the Netherlands) with completely different policies regarding abortion-related use of anti-D immunoglobulin to ultimately determine any benefit in use. In the Netherlands, the policy is to offer anti-D immunoglobulin to Rh-negative women having spontaneous abortions over 10 weeks 0 days gestation and induced abortions over 7 weeks 0 days. In Canada, it is recommended to offer all Rh-negative women having induced or spontaneous abortions anti-D immunoglobulin.

Methods

We used public databases to obtain the population data, the number of births, the abortion rates (the percentage of women having induced abortions in one year) and the Rh-negativity rates (percentage of Rh negative women) in Canada and the Netherlands. Both countries do routine prenatal blood screening and we obtained the rates of clinically significant antibodies from public databases.

Results

In nearly 2 million blood samples from pregnant women in both Canada and the Netherlands, the prevalence of clinically significant antibodies was statistically lower in the Netherlands: 4.21 (95% CI: 4.12 to 4.30) and 4.03 (95% CI: 3.93 to 4.12) per 1000, respectively. Canada and the Netherlands had small differences in rates of abortion (1.9 per 100 vs 1.2 per 100) and of Rh negativity (13.0% vs 14.5%).

Conclusion

Despite different anti-D Ig treatment policies, we found a similar prevalence of clinically significant perinatal antibodies among women in Canada and the Netherlands.

Implications

Our findings suggest that The Dutch policy of not treating Rh-negative women having spontaneous abortions under 10 weeks’ or induced abortions under 7 weeks’ gestation can be safely adopted by other countries.

Rhesus disease: a global prevention strategy

After nearly five decades of effective prophylaxis in high-income countries, the incidence of rhesus haemolytic disease (also known as haemolytic disease of the fetus and newborn) has substantially decreased, and as a result, clinical experience of the disease among health-care providers is insufficient. By contrast, a worldwide study found that rhesus haemolytic disease continues to be a public health problem in low-income and middle-income countries, affecting annually in more than 150 000 children, and causing thousands of stillbirths, neonatal deaths, and cases of hyperbilirubinaemia with its sequelae (kernicterus and bilirubin-induced neurological dysfunction). Solutions to this problem will require the combined and integrated effort of physicians and other health-care workers, international agencies, manufacturers of the prophylactic agent (rhesus immunoglobulin), health policy makers, and governments of low-income and middle-income countries.

[Complications of termination of pregnancy]

The legalization of abortion in France allowed to disappear almost maternal deaths caused by induced abortions. Nevertheless, the practice of abortion in a medical framework is encumbered with a number of immediate complications. Similarly, the late consequences of the practice of surgical abortion have generated an abundant literature, which it is important to analyse, both to meet the legitimate concerns of patients as to prevent any spread of false ideas under the influence of movements opposed to abortion.

Pathology Consultation on Patients With a Large Rh Immune Globulin Dose Requirement

OBJECTIVES

To review the differential diagnosis and laboratory issues for women with a large calculated dose of Rh immune globulin (RhIG).

METHODS

A case-based approach is used to review the differential diagnosis of patients with a large calculated dose of RhIG, RhIG dosing for women with baseline elevations in hemoglobin F, the formulations of RhIG, and issues for the transfusion medicine service with the release of large doses of RhIG.

RESULTS

A large fetomaternal bleed after delivery requiring multiple doses of RhIG is rare. Such patients may require intravenous RhIG to avoid multiple injections. Patients with a large percentage of circulating fetal RBCs should be evaluated for a disorder of hemoglobin synthesis and, if present, should have quantification of the circulating fetal RBCs by flow cytometry.

CONCLUSIONS

Accurate laboratory evaluation of women with large fetomaternal bleeds is essential for appropriate RhIG administration.

Do Rh-negative women with first trimester spontaneous abortions need Rh immune globulin?

OBJECTIVE

To examine whether literature supports the use of Rh immune globulin in Rh-negative women with first trimester spontaneous abortions to prevent maternal sensitization to the fetal Rh antigen and subsequent fetal morbidity and mortality.

METHODS

We searched MEDLINE (1966-2005), the Cochrane Central Register of Controlled Trials, EMBASE (1990 to 2005), and the reference sections of the articles found. The search is considered updated to December of 2005. Search terms included vaginal bleeding, Rh negative, Rh immune globulin, RhoGAM, isoimmunization, sensitization, first trimester pregnancy, threatened, and spontaneous abortion.

RESULTS

The evidence to support the use of Rh immune globulin for a diagnosis of first trimester spontaneous abortion is minimal. There is a paucity of well-designed research that examines maternal sensitization or hemolytic disease of the newborn as an outcome in patients receiving, versus not receiving, Rh immune globulin in first trimester bleeding. There is significant evidence to demonstrate fetomaternal hemorrhage in first trimester spontaneous abortions; yet, no studies demonstrate subsequent maternal sensitization or development hemolytic disease in the fetus as a result of this hemorrhage.

CONCLUSION

In summary, there is minimal evidence that administering Rh immune globulin for first trimester vaginal bleeding prevents maternal sensitization or development of hemolytic disease of the newborn. The practice of administering Rh immune globulin to Rh-negative women with a first trimester spontaneous abortion is based on expert opinion and extrapolation from experience with fetomaternal hemorrhage in late pregnancy. Its use for first trimester bleeding is not evidence-based.

Prevention and management of RhD isoimmunization

An Rh-negative woman is at risk for developing Rh isoimmunization upon exposure to RhD antigens from her Rh-positive baby through fetal-maternal hemorrhage. The incidence of Rh isoimmunization and fetal hemolytic disease has decreased substantially since Rh immune globulin was introduced in 1968. When RhD sensitization does occur, careful follow-up of these mothers and judicious intervention can result in good outcomes for most pregnancies. Both Doppler assessment of middle cerebral artery peak systolic velocity and spectral analysis of amniotic fluid at 450 nm (DeltaOD 450) are useful in the diagnosis and management of fetal anemia.

Prevention of Rh alloimmunization

OBJECTIVE

To provide guidelines on use of anti-D prophylaxis to optimize prevention of rhesus (Rh) alloimmunization in Canadian women.

OUTCOMES

Decreased incidence of Rh alloimmunization and minimized practice variation with regards to immunoprophylaxis strategies.

EVIDENCE

The Cochrane Library and MEDLINE were searched for English-language articles from 1968 to 2001, relating to the prevention of Rh alloimmunization. Search terms included: Rho(D) immune globulin, Rh iso- or allo-immunization, anti-D, anti-Rh, WinRho, Rhogam, and pregnancy. Additional publications were identified from the bibliographies of these articles. All study types were reviewed. Randomized controlled trials were considered evidence of highest quality, followed by cohort studies. Key individual studies on which the principal recommendations are based are referenced. Supporting data for each recommendation is briefly summarized with evaluative comments and referenced.

VALUES

The evidence collected was reviewed by the Maternal-Fetal Medicine and Genetics Committees of the Society of Obstetricians and Gynaecologists of Canada (SOGC) and quantified using the Evaluation of Evidence guidelines developed by the Canadian Task Force on the Periodic Health Exam.

RECOMMENDATIONS

1. Anti-D Ig 300 microg IM or IV should be given within 72 hours of delivery to a postpartum nonsensitized Rh-negative woman delivering an Rh-positive infant. Additional anti-D Ig may be required for fetomaternal hemorrhage (FMH) greater than 15 mL of fetal red blood cells (about 30 mL of fetal blood). Alternatively, anti-D Ig 120 microg IM or IV may be given within 72 hours of delivery, with testing and additional anti-D Ig given for FMH over 6 mL of fetal red blood cells (12 mL fetal blood). (I-A) 2. If anti-D is not given within 72 hours of delivery or other potentially sensitizing event, anti-D should be given as soon as the need is recognized, for up to 28 days after delivery or other potentially sensitizing event. (III-B) 3. There is poor evidence regarding inclusion or exclusion of routine testing for postpartum FMH, as the cost-benefit of such testing in Rh mothers at risk has not been determined. (III-C) 4. Anti-D Ig 300 microg should be given routinely to all Rh-negative nonsensitized women at 28 weeks' gestation when fetal blood type is unknown or known to be Rh-positive. Alternatively, 2 doses of 100-120 microg may be given (120 microg being the lowest currently available dose in Canada): one at 28 weeks and one at 34 weeks. (I-A) 5. All pregnant women (D-negative or D-positive) should be typed and screened for alloantibodies with an indirect antiglobulin test at the first prenatal visit and again at 28 weeks. (III-C) 6. When paternity is certain, Rh testing of the baby's father may be offered to all Rh-negative pregnant women to eliminate unnecessary blood product administration. (III-C) 7. A woman with "weak D" (also known as Du-positive) should not receive anti-D. (III-D) 8. A repeat antepartum dose of Rh immune globulin is generally not required at 40 weeks, provided that the antepartum injection was given no earlier than 28 weeks' gestation. (III-C) 9. After miscarriage or threatened abortion or induced abortion during the first 12 weeks of gestation, nonsensitized D-negative women should be given a minimum anti-D of 120 microg. After 12 weeks' gestation, they should be given 300 microg. (II-3B) 10. At abortion, blood type and antibody screen should be done unless results of blood type and antibody screen during the pregnancy are available, in which case antibody screening need not be repeated. (III-B) 11. Anti-D should be given to nonsensitized D-negative women following ectopic pregnancy. A minimum of 120 microg should be given before 12 weeks' gestation and 300 microg after 12 weeks' gestation. (III-B) 12. Anti-D should be given to nonsensitized D-negative women following molar pregnancy because of the possibility of partial mole. Anti-D may be withheld if the diagnosis of complete mole is certain. (III-B) 13. At amniocentesis, anti-D 300 microg should be given to nonsensitized D-negativeesis, anti-D 300 microg should be given to nonsensitized D-negative women. (II-3B) 14. Anti-D should be given to nonsensitized D-negative women following chorionic villous sampling, at a minimum dose of 120 microg during the first 12 weeks' gestation, and at a dose of 300 microg after 12 weeks' gestation. (II-B) 15. Following cordocentesis, anti-D Ig 300 microg should be given to nonsensitized D-negative women. (II-3B) 16. Quantitative testing for FMH may be considered following events potentially associated with placental trauma and disruption of the fetomaternal interface (e.g., placental abruption, blunt trauma to the abdomen, cordocentesis, placenta previa with bleeding). There is a substantial risk of FMH over 30 mL with such events, especially with blunt trauma to the abdomen. (III-B) 17. Anti-D 120 microg or 300 microg is recommended in association with testing to quantitate FMH following conditions potentially associated with placental trauma and disruption of the fetomaternal interface (e.g., placental abruption, external cephalic version, blunt trauma to the abdomen, placenta previa with bleeding). If FMH is in excess of the amount covered by the dose given (6 mL or 15 mL fetal RBC), 10 microg additional anti-D should be given for every additional 0.5 mL fetal red blood cells. There is a risk of excess FMH, especially when there has been blunt trauma to the abdomen. (III-B) 18. Verbal or written informed consent must be obtained prior to administration of the blood product Rh immune globulin. (III-C) VALIDATION: These guidelines have been reviewed by the Maternal-Fetal Medicine Committee and the Genetics Committee, with input from the Rh Program of Nova Scotia. Final approval has been given by the Executive and Council of the Society of Obstetricians and Gynaecologists of Canada.

Is Rh immune globulin needed in early first-trimester abortion? A review

The prophylactic use of Rh immune globulin has been a medical success, protecting women who could be at risk from exposure to the Rh(D) antigen. Thus, it is not surprising that Rh(D) immunoprophylaxis has been extended from women with term pregnancies to all women with miscarriages, abortions, and ectopic pregnancies. In this article we review the existing medical literature to assess the risks of fetomaternal hemorrhage and Rh isoimmunization after complications of a first-trimester pregnancy, induced abortion, or ectopic pregnancy. The evidence to support the use of Rh immune globulin in the first trimester is sparse, but there is theoretic evidence of its necessity. Despite weak evidence to support its use, there is little risk.

RhD isoimmunization and current management modalities

OBJECTIVE

To review the literature on current perspectives and treatment of RhD isoimmunization.

DATA SOURCES

A search was conducted on MEDLINE and CINAHL, and supplemental articles/ bulletins were obtained from cited references and the Web site of the American College of Obstetricians and Gynecologists. Recent texts also were reviewed. Key search words: isoimmunization, Rho (d) immune globulin, fetal erythroblastosis, intrauterine blood transfusions, alloimmunization.

STUDY SELECTION

Articles and comprehensive works from indexed journals in the English language relevant to key words and published after 1995 were evaluated. Historically relevant periodicals and texts were also reviewed and selected.

DATA EXTRACTION

Data were extracted and organized under the following headings: testing of the antepartum patient, antepartum treatment of isoimmunization, testing of the postpartum patient, anti-D immune globulin, antepartum anti-D immune globulin prophylaxis, other antepartum and obstetric indications for anti-D immune globulin administration, postpartum anti-D immune globulin prophylaxis, nursing implications, and future possibilities.

DATA SYNTHESIS

RhD isoimmunized pregnancies continue to contribute to worldwide perinatal and neonatal morbidity and mortality. This review describes the basic knowledge necessary to care for these pregnancies and the current management modalities.

CONCLUSIONS

The management options for RhD compromised gestations continue to evolve almost as quickly as technological advances are made. Multiple areas of research in this field have surfaced, and nurses can become valuable members of these research teams. The literature also indicates that with the available knowledge and resources, the current rate of RhD isoimmunization can be further decreased with closer adherence to proposed management guidelines by all health care professionals.

Clinical experience with the prevention of Rh-isoimmunization: a historical comparative analysis

Clinical experience with prevention of Rh-immunization is reviewed. The pathogenesis of hemolytic disease and the chemistry of prophylaxis is explained. The factors which effect antigenic expression are delineated. The clinical indications for prevention of AMIS are reviewed. International data pertaining to Rhesonativ are presented from postpartum trials and antepartum trials. A protocol for antepartum administration of anti-Rh immunoglobulin is given.

Screening of Rh-antibodies in Rh-negative female infants with Rh-positive mothers

The sera of 96 consecutive Rh-negative female infants born to Rh-positive mothers were examined at birth, and sera from 88 of these infants were examined for the presence of Rh-antibodies at the ages of about three and eight months. A two-stage papain test and an AutoAnalyzer method were used for antibody screening and identification. Weak anti-D antibodies were found by the papain and AutoAnalyzer techniques in two cord sera, In neither case could the antibodies be demonstrated in samples taken on later occasions. Weak anti-D antibodies were found by the AutoAnalyzer technique but not by the manual methods in the sera of two other infants at the age of eight months. These antibodies could still be demonstrated by the same technique in samples taken about one month later. Though far from conclusively, the results support the "grandmother theory", but because of the low incidence of sensitization and uncertain nature of the anti-D antibodies demonstrable only by the AutoAnalyzer technique, anti-D prophylaxis is not recommended for newborn Rh-negative female infants with Rh-positive mothers.

Reduced dose of Rho(D) immune globulin following induced first-trimester abortion

A double-blind study of women after first-trimester abortion supports the efficacy of low-dose Rho(D) immune globulin (human) in the prevention of Rh sensitization. Twenty-seven per cent of patients demonstrated a fetomaternal blood leak based on Kleihauer-Betke stains. In follow-up testing, the percentage of positive titers and the absolute titer of detectable antibody at various intervals were related to the dose of administered immune globulin. This study confirmed the possible risk of sensitization in Rh-negative postabortal women and suggests the practical use of single low-dose immune globulin preparations in prevention.

Pulmonary hypoplasia in babies with severe rhesus isoimmunisation: a quantitative study

Analysis of lung weights of 96 infants dying with rhesus isoimmunisation has shown that the lung is considerably retarded in its growth. Detailed analysis of the lungs of six babies after pulmonary artery injection showed in all a reduction in airway number and thus acinar and artery number, suggesting arrest in growth before the 16th week of gestation. The alveoli were also of either abnormal number, size or maturity, suggesting a continuing effect in later foetal life. Total lung volume varied from the normal value in one case to one-quarter normal in the smallest lung.

Small dose anti-Rh therapy after first trimester abortion

The standard prophylactic dose of anti-Rh immunoglobulin used in the United States is 300 microgram. For use after spontaneous or induced abortion and diagnostic amniocentesis, this dose represents immunological "overkill". A 50 microgram dose has been effectively used for these patients in other countries but the specific products used were not equivalent to the products available in the USA. No evaluation of this 50 microgram dose has been conducted in the USA. This is a pilot study of 315 patients given a 50 microgram dose or a 300 microgram dose of anti-Rh immunoglobulin after first trimester abortion. No patient in either treatment group developed atypical blood group antibodies within 6 months. This finding confirms that 50 microgram of the American product is protective after first trimester abortion.

Endometrial aspiration in fertility control. A report of 500 cases

Outpatient endometrial aspiration was offered to patients who suspected that they were pregnant, but were within 5 to 21 days after failure of expected menstruation and had a uterus of normal size on pelvic examination. This is a report of 500 consecutive cases treated between September, 1973, and April, 1975. Histologic examination of the aspirated tissue was obtained on all 500 cases (100 per cent). Follow-up examination and urine pregnancy was obtained on 407 patients (81.4 per cent). Histologic evidence of pregnancy was obtained in 323 patients (64.6 per cent). Complications were limited to five infections (1 per cent), only one of which led to hospitalization of the patient, and failure to completely evacuate the pregnant uterus in 39 patients (12.1 per cetn of the 323 pregnant). Thirty-four of these had the uterus emptied by a second outpatient procedure and five patients were hospitalized to complete their abortion.

Transplacental passage of fetal red cells in abortion; increased incidence after curettage and effect of oxytocic drugs

In a study of early abortions (less than 16-week pregnancies) no significant increase in fetomaternal haemorrhage was found in patients having either threatened or incomplete abortions. A statistically significant increase in fetal cells in the maternal circulation, however, occurred after curettage. The administration of oxytocic drugs in conjunction with curettage in cases of incomplete abortion did not increase the incidence of transplacental passage of fetal erythrocytes when compared with curettage alone. Of the 81 patients curetted following abortion four had a feto-maternal haemorrhage of more than 0.2 ml. The largest amount of fetal blood found in the maternal circulation was 0.4 to 0.5 ml. Preliminary data evaluating the indirect Coombs test and enzyme-treated red cells in Rh-negative post-abortion cases suggest that this amount of blood is not a primary immunizing dose but a "booster" to preformed antibody.