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Head-to-body delivery by "two-step" approach: effect on cord blood hematocrit
Vincenzo Zanardo1, Catia Gabrieli, Federico de Luca
1Department of Obstetrics and Gynecology and Division of Neonatology, Policlinico Abano Terme, Abano Terme, Padua, Italy. vincenzo.zanardo@libero.it
Background:
There is no study to support a relationship between placental transfusion and active management techniques of the second stage of labor.
Objective:
To examine the association between head-to-body delivery by a "two-step" approach (which includes waiting for the next contraction to deliver the shoulders) and its effect on the amount of blood that remains in the infant's circulation at birth.
Study Design:
Observational study on 500 consecutive, singleton, and at term deliveries from January to June 2012 in Policlinico Abano Terme, Abano Terme, Italy. Umbilical artery hematocrit (Htc) was evaluated in reference to contemporary tested pH values, involving neonates vaginally delivered by the "two-step" approach and by cesarean section, respectively.
Results:
Head-to-body delivery by the "two-step" approach significantly increased Htc values with respect to cesarean delivery (50.16% versus 47.24%, p < 0.001) and at the same time reduced pH (7.31 ± 0.09 versus 7.33 ± 0.06, p = 0.007) in umbilical artery. In addition, Htc levels for this group were significantly negatively correlated with umbilical artery pH (r = -0.137, p < 0.018).
Conclusion:
Head-to-body delivery by the "two-step" approach increases the red cell mass in term infants without any clinical risk of neonatal acidemia.
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