Dreyfuss E, Yahalom V, Barer Y, Ambar I, Pardo A, Shmueli A, Houri O, Hadar E, Barbash-Hazan S
Helen Schneider Hospital for Women, Rabin Medical Center, Petach Tikva, Israel.
Gray Faculty of Medical and Health Sciences, Tel Aviv University, Tel Aviv, Israel.
Transfusion. 2025 Sep;65(9):1707-1715. doi: 10.1111/trf.18356. Epub 2025 Jul 25.
During pregnancy, exposure to fetal red blood cell antigens can trigger alloimmunization. To enable safe transfusion of compatible blood for pregnant individuals where urgent surgery might be necessary, blood bank standards mandate a valid blood type and antibody screening every 72 h ("3-day rule"). This practice requires frequent blood drawings contributing to patient discomfort and costs. To investigate if this practice is required, we evaluated the proportion of pregnant individuals who develop clinically significant alloantibodies within 72 h of a previous negative antibody screen.
Retrospective cohort of RhD-positive pregnant individuals with initial negative antibody screens, undergoing repeated screens at variable intervals. Seroconversion rates were compared with healthy male blood donors. Characteristics of pregnant individuals with and without seroconversion were analyzed.
Among 8659 RhD-positive pregnant individuals with initial negative antibody screens, 56 (0.6%) converted to a positive antibody screen, while only 15 (0.2%) developed clinically significant alloantibodies. Of these 15, only one converted within 3 days of testing, while others converted within 5-95 days. Two of the 15 women received a blood transfusion, 8-97 days before seroconversion. No male donors seroconverted during 9 months of follow up. Pregnant individuals with seroconversion were more likely to have systemic lupus erythematosus and antiphospholipid antibody syndrome.
Only one pregnant individual developed clinically significant alloantibodies within 72 h of a negative screening, compared to none of the control group. For pregnant individuals without recent transfusion, extending antibody screening intervals to 1 week appears safe.
孕期接触胎儿红细胞抗原可引发同种免疫。为了能在可能需要紧急手术的孕妇中安全输注相容血液，血库标准规定每72小时（“3天规则”）进行一次有效的血型和抗体筛查。这种做法需要频繁采血，给患者带来不适并增加成本。为了研究是否需要这种做法，我们评估了在前一次抗体筛查为阴性后的72小时内产生具有临床意义的同种抗体的孕妇比例。
对RhD阳性且初次抗体筛查为阴性的孕妇进行回顾性队列研究，她们接受了不同间隔的重复筛查。将血清学转换率与健康男性献血者进行比较。分析了发生血清学转换和未发生血清学转换的孕妇的特征。
在8659名初次抗体筛查为阴性的RhD阳性孕妇中，56名（0.6%）抗体筛查转为阳性，而只有15名（0.2%）产生了具有临床意义的同种抗体。在这15名中，只有1名在检测后3天内发生转换，其他在5 - 95天内转换。这15名女性中有2名在血清学转换前8 - 97天接受了输血。在9个月的随访中，没有男性献血者发生血清学转换。发生血清学转换的孕妇更有可能患有系统性红斑狼疮和抗磷脂抗体综合征。
与对照组无一例发生相比，只有一名孕妇在阴性筛查后的72小时内产生了具有临床意义的同种抗体。对于近期未输血的孕妇，将抗体筛查间隔延长至1周似乎是安全的。
