The objective of this study was to review the results of umbilical cord drug screening in twins and triplets (multiples) to compare the detected drug(s) and/or drug metabolite(s). Results that did not agree between multiples were considered mismatched and were investigated. A retrospective analysis was conducted using de-identified data from a national reference laboratory, and results were compared with data from an academic medical center, where detailed medical chart review was performed. Umbilical cord was analyzed for stimulants, sedatives, opioids and other drugs and metabolites. For the reference laboratory dataset, 23.3% (n = 844) of 3,616 umbilical cords from twins (n = 3,550) or triplets (n = 66) were positive for one or more drugs and/or metabolites. Of these, mismatched results were identified for 37 sets of twins (2.1%) and no sets of triplets. The most frequent mismatches were found in opioids (n = 24), with morphine (n = 5) being the most mismatched of any single analyte in the panel. Mismatches for the marijuana metabolite 11-nor-9-carboxy-delta-9-tetrahydrocannabinol (9-COOH-THC) in the reference laboratory dataset occurred in 6 of 737 sets of twins (0.8%) and no triplets. For the academic medical center dataset, 21.9% (n = 57) of 260 umbilical cords tested positive for one or more drugs and/or metabolite(s). Of these, four mismatches (3.2%) were identified, including 9-COOH-THC (n = 2), phentermine (n = 1) and oxycodone (n = 1), all involving twins. All involved cases where the discrepant analyte was likely present in the negative twin but either slightly below the reporting cutoff threshold or failed analytical quality criteria. Mismatched results of umbilical cord drug screening occur in less than 4% of twins and most often occur when the analyte is slightly above the reporting cutoff in just one infant.

中文翻译：

---

多胞胎脐带药物筛查：参考实验室和学术医疗中心的经验

本研究的目的是回顾双胞胎和三胞胎（多胞胎）的脐带药物筛查结果，以比较检测到的药物和/或药物代谢物。倍数之间不一致的结果被认为是不匹配的，并进行了调查。使用来自国家参考实验室的去识别数据进行回顾性分析，并将结果与​​来自学术医疗中心的数据进行比较，在那里进行了详细的病历审查。分析了脐带中的兴奋剂、镇静剂、阿片类药物和其他药物和代谢物。对于参考实验室数据集，来自双胞胎 (n = 3,550) 或三胞胎 (n = 66) 的 3,616 根脐带中有 23.3% (n = 844) 对一种或多种药物和/或代谢物呈阳性。其中，37 对双胞胎（2. 1%）并且没有三胞胎组。最常见的错配出现在阿片类药物 (n = 24) 中，吗啡 (n = 5) 是该组中任何单一分析物中最不匹配的。参考实验室数据集中的大麻代谢物 11-nor-9-carboxy-delta-9-tetrahydrocannabinol (9-COOH-THC) 不匹配发生在 737 对双胞胎中的 6 对 (0.8%) 并且没有三胞胎。对于学术医疗中心数据集，260 根脐带中有 21.9%（n = 57）的一种或多种药物和/或代谢物检测呈阳性。其中，确定了四个错配 (3.2%)，包括 9-COOH-THC (n = 2)、芬特明 (n = 1) 和羟考酮 (n = 1)，均涉及双胞胎。在所有涉及的情况下，差异分析物可能存在于阴性双胞胎中，但略低于报告截止阈值或未达到分析质量标准。