The proportion of Tregs among CD4+ T cells was only 2.9% in NEC newborns compared to 6.6% in normal newborns without NEC.22 Tregs numbers were significantly lower in FGR cord blood than in normal cord blood, accompanied with suppressed expression of Foxp3.15 Preeclampsia is the major cause for pregnant women and perinatal death, and FGR is the most common consequence of preeclampsia.23 In rat preeclampsia‐induced FGR model, the total numbers of CD3+, CD4+ and CD8+ T cells in FGR placenta were comparable to control placenta. Here, CD4 is linked to preeclampsia.