Diagnostic value of laboratory monitoring to predict severe hemolytic disease of the fetus and newborn in non-D and non-K-alloimmunized pregnancies.

BACKGROUND: Pregnant women are routinely screened for red blood cell (RBC) antibodies early in pregnancy. If RBC-alloantibodies are detected, repeated laboratory testing is advised to timely identify pregnancies at high risk for severe hemolytic disease of the fetus and newborn (HDFN). We assessed for RBC alloantibodies, other than anti-D or anti-K, cut-offs for the titer and the antibody dependent cellular cytotoxicity (ADCC) test to select high-risk cases. To advise on test repeat intervals, and to avoid unnecessary testing, we evaluated the chance for exceeding the cut-offs for Rh antibodies other than anti-D, Jk, Fy, and S/s antibodies. STUDY DESIGN AND METHODS: Diagnostic value of antibody titer and ADCC test was determined with data from a prospective index-cohort study, conducted in 2002-2004. Laboratory test outcomes were from a recent observational cohort (2015-2016). RESULTS: A titer cut-off of ≥16 showed a sensitivity of 100% (95% CI:73-100%) and a positive predictive value (PPV) of 17% (95% CI:14%-20%). The percentage of pregnancies reaching a titer above the cut-off of ≥16 varied from 0% for anti-Jka /Jkb (n = 38) to 36% for anti-c (n = 97). The ADCC test showed no cut-off with a 100% sensitivity. However, in cases with a titer ≥16 and an ADCC test ≥30% a PPV of 38% was obtained to detect severe HDFN. CONCLUSION: A titer cut-off of ≥16 is adequate to detect all cases at risk for severe HDFN; the ADCC test may add a more accurate risk estimation. Repeated testing is recommended in pregnancies with anti-c. In pregnancies with other Rh antibodies a repeated test in the third trimester is recommended.

Facilitators and barriers for RhD-immunized women to become and remain anti-D donors.

BACKGROUND: The successful introduction of prophylaxis with anti-RhD immunoglobulin has resulted in a significant decline of pregnancy-related RhD immunizations but also has decreased the availability of naturally immunized women as (new) anti-D donors. An influx of new donors is necessary to maintain a sufficient pool of anti-D donors. We investigated motivators, barriers, and predictors for anti-D donorship in RhD-immunized women. STUDY DESIGN AND METHODS: A mixed-methods design was applied, including focus group discussions and questionnaires. Two focus groups (including 11 women) served as input for the questionnaire. RESULTS: In total, 47.6% of 750 anti-D donors and potential donors completed the questionnaire (50.4% donors; 38% nondonors; 11.6% former donors). Almost 70% of the nondonors would have become donors if they had known about the possibility. Travel time investment was reported as a disadvantage; one-half of donors mentioned no disadvantages. Motivators for anti-D donorship were "doing something in return" (31.2%) and "preventing others having a sick child or losing a child" (33.9%). In multivariable analysis, living single (odds ratio, 5.8; p = 0.02) and living partnered without resident children (odds ratio, 7.9; p = 0.03), compared with living partnered with children, were predictors for anti-D donorship. Not being registered as an organ donor (odds ratio, 0.25; p < 0.001) predicted that the individual would not be an anti-D donor. CONCLUSION: The main barrier for anti-D donorship was a lack of knowledge. Positive predictors of anti-D donorship were living without resident children, altruism, and being registered as an organ donor. A blood bank should develop targeted recruitment strategies with a focus on spreading knowledge about anti-D donorship among RhD-immunized women.

Possible relationship between general and pregnancy-related anxiety during the first half of pregnancy and the birth process: a prospective cohort study.

OBJECTIVES: The rate of interventions during childbirth has increased dramatically during the last decades. Maternal anxiety might play a role in the progress of the labour process and interventions during labour. This study aimed to identify associations between anxiety in the first half of pregnancy and the birth process, including any interventions required during labour. In addition, differences in the associations by parity and ethnicity were explored. DESIGN: Prospective cohort study. SETTING: Primary care midwifery practices and secondary/tertiary care obstetric practices in Amsterdam, participating in the multiethnic ABCD (Amsterdam Born Children and their Development) study (participation rate 96%; response 8266/12 373 (67%)). PARTICIPANTS: Included were women with singletons, alive at labour start, with a gestational age ≥24 weeks (n=6443). INDEPENDENT VARIABLE: General anxiety (State-Trait Anxiety Inventory state) and pregnancy-related anxiety (Pregnancy-Related Anxieties Questionnaire (PRAQ)) were self-reported in the first half of pregnancy. OUTCOMES: Associations between both forms of anxiety and several indicators of the birth process were analysed. Subgroup analyses were performed for parity and ethnicity. RESULTS: The prevalence of high general anxiety (State-Trait Anxiety Inventory score ≥43) and pregnancy-related anxiety (PRAQ score ≥P90) were 30.9% and 11.0%, respectively. After adjustment, in nulliparae, both general anxiety and pregnancy-related anxiety were associated with pain relief and/or sedation (OR for general anxiety 1.23; 95% CI 1.02 to 1.48; OR for pregnancy-related anxiety 1.45; 95% CI 1.14 to 1.85). In multiparae, general anxiety was associated with induction of labour (OR 1.53; 95% CI 1.16 to 2.03) and pregnancy-related anxiety was associated with primary caesarean section (OR 1.66; 95% CI 1.02 to 2.70). Associations were largely similar for all ethnicities. CONCLUSIONS: High levels of general and pregnancy-related anxiety in early pregnancy contribute modestly to more interventions during the birth process with similar associations between ethnic groups, but with some differences between nulliparae and multiparae.