ABSTRACT
The Leboyer birth method requires that the newly born infant is placed on the mother's
abdomen and the cord is clamped when it stops pulsating. This investigation was done
to study the effect of Leboyer childbirth on neonatal circulation during the first
5 days after birth. Hematocrit, blood viscosity, left and right ventricular output,
and cerebral blood flow velocities in the arteria carotis interna, arteria cerebri
anterior, and truncus coeliacus were studied in 15 full-term neonates with early (less
than 10 seconds) cord clamping and 15 full-term neonates delivered according to Leboyer
(cord clamping after 3 minutes) on day 1 (2 to 4 hours after birth) and day 5. The
fetal placental blood volume decreased from 42 ± 8 mL/kg (mean ± SD) of neonatal body
weight after early cord clamping to 19 ± 7 mL/kg after Leboyer delivery. Neonatal
blood volume, calculated from the fetal placental blood volume, was 32% higher in
the Leboyer group compared with the early cord-clamped infants. In the infants with
early cord clamping, hematocrit, and blood viscosity did not change significantly
during the first 5 days. After Leboyer birth, the hematocrit rose from 0.51 ± 0.05
in cord blood to 0.62 ± 0.06 at 2 to 4 hours of age, thereby increasing blood viscosity
by 32%. Stroke volume, heart rate, cardiac output, left-to-right shunt across the
ductus arteriosus, and blood flow velocity in the truncus coeliacus were similar in
both groups and did not change during the first 5 days. In both groups, blood pressure,
flow resistance (blood pressure to left ventricular output) and cerebral flow velocities
increased significantly (p <0.05) between day 1 and day 5. On day 1, red blood cell flow was 25% higher in the
Leboyer group compared with the early cord-clamped infants. Vascular hindrance (resistance
to blood viscosity), an indicator of vasoconstriction, was 25% lower in the Leboyer
group, thereby suggesting marked vasodilation. We conclude that the rise in blood
viscosity after Leboyer delivery does not adversely affect blood circulation due to
compensatory vasodilation.
Keywords
Cardiac output - cerebral blood flow - Doppler sonography - gastrointestinal blood
flow - Leboyer childbirth
