ABO blood type concordance-dependent variations in umbilical cord blood: Insights from twin pregnancies

Umbilical cord blood (UCB) is a rich source of hematopoietic stem and progenitor cells for regenerative medicine. This study characterized the cellular composition of UCB from twin pregnancies to identify blood type concordance (BTC)-related differences.

A cross-sectional study was conducted at the Vinmec Tissue Biobank, involving 128 twin deliveries (2019-2023). Linear correlation and mixed-effect modeling were employed to analyze relationships between cellular factors and BTC in twins.

Maternal and gestational ages were 31.9 ± 5.56 years and 36.7 ± 1.42 weeks. Neonatal weight averaged 2470.68 ± 382.5 g, with ABO blood type discordance (ABO-BTD) twins significantly heavier than ABO-BTC twins (p < 0.05). UCB volume exceeded 100 mL, positively correlating with birth weight and cellular yields. BTC twins exhibited higher pre-processing mononuclear cell (MNC) and lymphocyte-monocyte (L-M) counts and post-processing white blood cell (WBC) and MNC counts. Recovery rates for total nucleated cells (TNCs) and MNCs were 86.14 ± 15.72% and 96.47 ± 17.77%. CD34+ cell counts were higher in the BTD twins (p < 0.05), while hematocrit was lower (p < 0.05). Strong positive correlations were found between UCB volume and TNC, MNC, and CD34+ counts, whereas hematocrit showed weak or negative associations. Mixed-effect modeling confirmed higher TNC and WBC counts in BTD twins before and after processing (p < 0.05), independent of intra-pair variability.

ABO-BTC significantly influences UCB cellular yield, with ABO-BTD twins offering superior hematopoietic stem cell recovery potential for cord blood banking and clinical use.