Understanding in-utero transfer of antiretrovirals is critical for interpreting safety. Hair levels measure cumulative exposure. We measured tenofovir concentrations in hair at delivery among women living with HIV receiving tenofovir-disoproxil-fumarate-based treatment and their infants using liquid chromatography/tandem mass-spectrometry. Among 103 mother-infant pairs, the mean log₁₀-ratio of infant-to-maternal tenofovir levels was 1.08 (95% CI 0.97-1.20). TFV transfer was 60% lower from mothers who had preterm deliveries compared to term and 42% lower from mothers who had C-section deliveries compared to vaginal. Like prior studies assessing transfer via short-term measures (plasma, cord blood, amniotic fluid), we found high cumulative transfer using hair.

中文翻译：

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替诺福韦在子宫内从母亲转移到胎儿的程度：对美国队列中出生时收集的毛发样本进行配对分析。

了解抗逆转录病毒药物的子宫内转移对于解释安全性至关重要。头发水平衡量累积暴露程度。我们使用液相色谱/串联质谱法测量了接受基于富马酸替诺福韦二吡呋酯治疗的艾滋病毒感染者及其婴儿分娩时头发中的替诺福韦浓度。在 103 对母婴中，母婴替诺福韦水平的平均 log _{10比率为 1.08 (95% CI 0.97-1.20)。}与足月分娩相比，早产母亲的 TFV 移植率低 60%，剖腹产母亲的 TFV 移植率比顺产者低 42%。与之前通过短期措施（血浆、脐带血、羊水）评估转移的研究一样，我们发现使用头发的累积转移率较高。