Postnatal transfer of blood from the placenta to
the lungs
Budin (1875) measured the blood that drained out of
the umbilical vessels when the cord was cut at varying
intervals of time [1]. In 32 cases, the cord was not
tied until pulsations had ceased, with an average
yield of 11.2 cc of residual blood. In 30 cases, after
immediate ligation of the cord, the average was 98.4
cc.
Schucking (1877) described the blood recovered in
Budin's experiments as "reserve blood," which he said
was intended to fill the pulmonary vessels [2]. This
certainly makes intuitive sense because the most
important transition from fetal to postnatal life is the
transfer of respiratory function from the placenta to
the lungs. Schucking weighed each infant at the time
of delivery, then again after tying of the cord. Infants
gained from 30 to 110 grams when the cord was not
tied. Babies whose cords were tied immediately had
a more rapid pulse and gained weight more slowly,
whereas those whose cords were tied late had a
slower pulse and regained their birth weight in four to
six days. Schucking observed no jaundice in the
latter group.
Schucking also commented that he observed no
jaundice in the infants whose cords were tied late.
The problem of kernicterus, associated with bilirubin
staining of selective subcortical nuclei, was a subject
already under discussion [3]. The experiments of
Budin and Schucking are early examples of what are
now referred to as "randomized controlled trials" or
RCTs. That they assigned some infants to groups for
early ligation of the umbilical cord, indicates that
waiting for pulsations of the cord to cease was not
universally practiced. Both Budin and Schucking
concluded that it was best to wait for pulsations to
cease.
An infant that comes to term healthy no doubt has
many reserves, and clearly is able to overcome many
hazards of birth, including those inflicted by birth
attendants. However, children still are not followed
into their school years after random assignment to
the group for immediate clamping of the cord in RCT
experiments. Further, now clamping the cord within
15 or 20 seconds following birth is the norm, and
concerns over low Apgar scores or "respiratory
depression" at birth are beginning to be looked at [4,
5].
Baskett et al., in their paper on respiratory
depression at birth, reported a delay of up to 3
minutes in initiating and maintaining respiration in 5.2
per 1000 infants after birth [5]. Infants with an Apgar
score less than 3 at 5 minutes numbered 1 per 1000,
and neonatal seizures occurred in 0.7 per 1000.
Infants with at least one of the three measures
yielded a composite outcome of 6.2 per 1000.
These statistics closely resemble those for the
increasing prevalence of autism. For example, in
2006 the CDC website, provided prevalence rates for
autism spectrum disorders (ASDs) between 2 and 6
per 1,000 individuals [6]. Putting it another way, they
state that between 1 in 500 (2/1000) to 1 in 166
(6/1000) children have an ASD.
Most infants breathe immediately at birth, thus the
effects of immediate clamping of the cord might have
appeared to be only of academic interest in the days
of Budin and Schucking, when the norm was to follow
nature's plan, and wait for pulsation of the cord to
cease.
- Budin, P (1875) A quel
moment doit-on pratiquer la
ligature du cordon ombilical?
- Schucking, A (1877) Zur
Physiologie der
Nachgeburtsperiod.
Untersuchungen ueber den
Placentarkreislauf nach der
Geburt des Kindes.
- Orth J (1875) Ueber das
Vorkommen von
bilirubinkrystallen bei
neugeborenen kindern.
- Milsom I et al. (2002)
Influence of maternal,
obstetric and fetal risk
factors on the prevalence of
birth asphyxia at term in a
Swedish urban population.
- Baskett TF et al (2006)
Predictors of respiratory
depression at birth in the
term infant.
- www.cdc.gov/ncbddd/autism/
- Budin, P (1875) A quel moment doit-on pratiquer la ligature du cordon
ombilical? Progres Medical 3:750-751, 765-767, (1876) 4:2-3.
- Schucking, A (1877) Zur Physiologie der Nachgeburtsperiod.
Untersuchungen ueber den Placentarkreislauf nach der Geburt des
Kindes. Berliner Klinishe Wochenschrift 1877 #1 (1 Jan):5-7 and (8 Jan):
18-21
- Orth J. Ueber das Vorkommen von bilirubinkrystallen bei neugeborenen
kindern. Virchows Arch Pathol Anat Physiol Klin Med 1875;63:447–462.
- Milsom I, Ladfors L, Thiringer K, Niklasson A, Odeback A, Thornberg E.
Influence of maternal, obstetric and fetal risk factors on the prevalence
of birth asphyxia at term in a Swedish urban population. Acta Obstet
Gynecol Scand. 2002 Oct;81(10):909-17.
- Baskett TF, Allen VM, O'Connell CM, Allen AC. Predictors of respiratory
depression at birth in the term infant. BJOG. 2006 Jul;113(7):769-74.
- www.cdc.gov/ncbddd/autism/