Placental Blood Drainage Shortens Duration of the Third Stage of Labor in Women Slowly Administered 20 IU Oxytocin

Abstract

Objective: Prolongation of the third stage of labor may cause serious postpartum complications. Thus, timely expulsion of the placenta is essential for preventing complications of the third stage of labor. We conducted a prospective cohort study to determine the effect of placental cord drainage on the duration of the TSL in women administered intravenous oxytocin during this stage.
Study Design: This was a prospective cohort study in which 112 low risk pregnant women were allocated to the study. There were 53 women in the placental cord drainage group, and 59 women in the cord clamping group without drainage. Immediately after fetal delivery, intravenous infusion of 20 IU oxytocin in 500 mL Ringers’ Lactate was started and infused within 2 hours in women in both groups. Outcome measures were the third stage duration and hemoglobin differences between admission and the postpartum sixth hour.
Results: There were no significant differences between the two groups with regard to duration of stages 1 and 2 of labor, hemoglobin level on admission, and at the postpartum sixth hour, and hemoglobin differences between admission and the postpartum sixth hour. The median third stage duration in the study group was 3.40 (range: 0.35-16.20) minutes, and 5.10 (range: 2.30-11.00) minutes in the control group. This difference between the groups was statistically significant (p

Full text

1
Experimental
&
Clinical Article
Placental Blood Drainage Shortens Duration of the Third Stage of
Labor in Women Slowly Administered 20 IU Oxytocin
Metin KABA1, Yaprak ENGİN ÜSTÜN1, Elif Gül YAPAR EYİ1, Hakan TİMUR1, Bekir Serdar ÜNLÜ1,
Aysegül ÖKSÜZOĞLU1
Ankara, Turkey
ABSTRACT
OBJECTIVE: Prolongation of the third stage of labor may cause serious postpartum complications.
Thus, timely expulsion of the placenta is essential for preventing complications of the third stage of labor.
We conducted a prospective cohort study to determine the effect of placental cord drainage on the du-
ration of the TSL in women administered intravenous oxytocin during this stage.
STUDY DESIGN: This was a prospective cohort study in which 112 low risk pregnant women were al-
located to the study. There were 53 women in the placental cord drainage group, and 59 women in the
cord clamping group without drainage. Immediately after fetal delivery, intravenous infusion of 20 IU
oxytocin in 500 mL Ringers’ Lactate was started and infused within 2 hours in women in both groups.
Outcome measures were the third stage duration and hemoglobin differences between admission and
the postpartum sixth hour.
RESULTS: There were no significant differences between the two groups with regard to duration of
stages 1 and 2 of labor, hemoglobin level on admission, and at the postpartum sixth hour, and hemo-
globin differences between admission and the postpartum sixth hour. The median third stage duration in
the study group was 3.40 (range: 0.35-16.20) minutes, and 5.10 (range: 2.30-11.00) minutes in the con-
trol group. This difference between the groups was statistically significant (p<0.01).
CONCLUSION: Placental cord drainage reduces the third stage duration following vaginal deliveries in
patients receiving intravenous oxytocin. Placental cord drainage is simple, does not require additional
cost, and is applicable for every delivery.
Keywords: Third stage of labori, Active management of the third stage, Placental cord drainage,
Oxytocin, Expectant management
1Department of Obstetrics and Gynecology Zekai Tahir Burak Women’s
Health Education and Research Hospital, Ankara
Address of Correspondence: Metin Kaba
Akdeniz University Faculty of Medicine
Department of Obstetrics and
Gynecology Antalya, Turkey
metinkaba12@hotmail.com
Submitted for Publication: 11.07.2016
Accepted for Publication: 20.09.2016
Obstetrics; Maternal Fetal Neonatal Medicine
Gynecol Obstet Reprod Med 2016;22 (Article in Press)
Introduction
The third stage of labor (TSL) is defined as the time inter-
val between delivery of the baby and the expulsion of the pla-
centa. After delivery of the baby, health care providers usually
give attention to the newborn. But this stage is also important
for the woman who gave birth. Prolongation of the TSL leads
to an increased likelihood of maternal morbidity and mortality
and TSL-related complications, which include uterine atony,
retained placenta, postpartum hemorrhage (PPH), hemor-
rhagic shock, and even maternal death (1,2). Reported child-
birth-related maternal mortality is approximately 250.000 and
300.000 in the world annually (3). The majorities of these
mortalities are caused by complications during the TSL, and
most commonly are from uterine atony and PPH (3). The
timely expulsion of the placenta and an efficient uterine con-
traction to cease bleeding are important parts of the TSL in
preventing complications. Placental delivery is essential in al-
lowing the uterus to contract and decrease blood loss during
the TSL. Placental expulsion depends on the separation of the
placenta from the uterine wall, capillary hemorrhage, uterine
muscle contractile ability after placental separation, maternal
effort, and gravity of the placenta (4,5). Separation of the pla-
centa from the uterine wall is usually completed within 15
minutes in 90% of women after a fetal delivery (2,6).

Gynecology Obstetrics & Reproductive Medicine 2016;22:0 2
Prolongation of the TSL increases the development of PPH,
which is responsible for one quarter of maternal deaths glob-
ally, one third of all pregnancy-related deaths in Africa and
Asia, and approximately 140.000 deaths annually (7,8).
Preventive measures to decrease complications from the
TSL are recommended for all women undergoing childbirth
(9). Interventions to prevent TSL complications are called ac-
tive management of the third stage of labor (AMTSL). These
interventions include early umbilical cord clamping, adminis-
tration of an oxytocic agent, and controlled cord traction until
delivery of the placenta (3,8). Placental cord drainage is also
considered as an AMTSL method. Placental cord drainage fa-
cilitates placental delivery in both vaginal and cesarean sec-
tion deliveries (10,11). Releasing the maternal side of the cord
clamp and allowing the drainage of placental blood has been
recommended by many obstetricians to facilitate the delivery
of the placenta in vaginal deliveries (11).
We conducted this prospective cohort trial to determine
whether placental cord drainage would shorten the TSL dura-
tion in low-risk pregnant women receiving 20 IU oxytocin in
500 mL Ringer’s Lactate (RL) intravenous infusion (IV)
within 2 hours.
Material and Method
This study was undertaken between 1 February and 30
June 2010 in the obstetric unit of the Zekai Tahir Burak
Women's Health Education and Research Hospital, Ankara,
Turkey. The study was approved by the Institutional Ethics
Committee and performed in accordance with the Helsinki
Declaration (Institutional ethical approval no: 19/04/2010/6).
On admission to the labor room, a detailed history, vaginal
examination, and blood count estimation were carried out with
all patients. Eligible patients were informed about the study
and written informed consent was obtained from each patient.
A total of 112 women who had a vaginal delivery completed
the trial. There were 53 (47.3%) women in the study group
and 59 (52.6%) in the control group. Inclusion criteria were
singleton cephalic presentation pregnancies, patients willing
to give written informed consent and pregnancies between 37
and 42 weeks of gestational age. Exclusion criteria were in-
trauterine fetal demise, antepartum hemorrhage, malpresenta-
tion, hypertensive disorders, history of medical disorders,
multiple pregnancy, chorioamnionitis, and coagulation abnor-
malities. Fetal and maternal monitoring during the first and
second stages of labor were carried out. In cases where aug-
mentation or induction of labor was indicated, an oxytocin in-
fusion protocol was applied.
When the cervix was dilated to 10 cm and the fetus arrived
at the perineum, the pregnant woman was transferred to the
delivery ward. Following delivery of the neonate, the umbili-
cal cord was clamped with two clamps, cut between the
clamps, and the neonate was handed to the nurse who was ed-
ucated for neonatal care. In the placental cord drainage group,
after the cord was clamped and cut, immediate unclamping
was performed on the maternal side of the cord and the blood
in the placenta was allowed to drain freely. In the control
group, the umbilical cord remained clamped until placental
delivery. Immediately after fetal delivery, intravenous infusion
of 20 IU oxytocin in 500 mL RL was started and transfused
within 2 hours for women in both groups. Upon observing
signs of placental separation (gush of blood from the vagina,
descent of the umbilical cord, and an increase in the height of
the uterus in the abdomen as the lower segment distends) and
once the placenta came into the vagina, it was pulled out. The
duration of the TSL was determined with a watch controlled
by the same physician. Complete removal of the placenta and
membranes was then confirmed. Any adverse event such as a
prolonged third stage, a retained placenta, uterine atony, post-
partum hemorrhage, and any vaginal tear was noted. If the pla-
centa was not delivered after 30 minutes, it was considered a
retained placenta. After completion of the TSL, the woman
was transferred to the recovery room. Maternal pulse, blood
pressure, and temperature were recorded within 15 minutes in
the first hour and then hourly for the following six hours. At
the postpartum sixth hour, a blood sample was taken to evalu-
ate maternal hemoglobin levels.
All statistical analyses were performed using the Statistical
Package for Social Sciences software, version 15.5 (SPSS,
Chicago, IL, USA). Student’s t-test and Mann-Whitney U test
were used for statistical analyses. Parametric test results are
presented as mean ± standard deviation; nonparametric test re-
sults are presented as a median with minimum and maximum
values. The probability of the null hypothesis was set to a 0.05
value. From a total of 112 women, data were analyzed from 53
women in the placental drainage with oxytocin group and
from 59 women in the oxytocin alone group.
Results
Demographic characteristics of the women in the two
groups were similar with regard to age, body mass index
(BMI), gravidity, parity, weeks of gestation, and fetal birth
weight; thus, these results demonstrate that the groups were
similar to each other and comparable (Table 1). There was no
significant difference between the groups with regard to the
duration of the first and second stages of labor with p values
of 0.226 and 0.105, respectively. However, the duration of the
TSL was significantly shorter in the placenta drainage group
than in the oxytocin alone group (p <0.01) (Table 2). In the
oxytocin alone group, there was a single placental retention
that was extracted with manual intervention under general
anesthesia.

3Kaba M. Engin Üstün Y. Yapar Eyi EG. Timur H. Ünlü BS. Öksüzoğlu A.
Discussion
The present study demonstrated that placental cord
drainage shortens the duration of the third stage of labor in
women who were administered an intravenous infusion of 20
IU oxytocin. Prolonged TSL is the major cause of maternal
morbidity and mortality worldwide (12). When the TSL is
prolonged, uterine contractile abilities may decrease and
blood flow from uterine vessels to the placental bed continues.
Inefficient uterine contraction may lead to excessive blood
loss from the placental bed and result in PPH (1,13). PPH is
commonly defined as a blood loss of 500 mL or more within
24 hours of giving birth (14). Although it is almost entirely a
preventable condition, PPH is the most serious complication
in obstetric practices, occurs in approximately 4% of vaginal
deliveries, and is the major cause of maternal deaths from
hemorrhage during childbearing (16). Two thirds of PPH cases
occur in women with no previously known risk factors. Thus,
all pregnant women are considered to be at risk for this condi-
tion (17). The degree of blood loss associated with placental
separation and delivery depends on how quickly the placenta
separates from the uterine wall and how effectively the uterine
muscle contracts around the placental bed and the uterine
blood vessels (3). If the placenta is not delivered within 10
minutes, the risk of PPH increases (18). Therefore, any inter-
vention for shortening the duration of the TSL and preventing
complications becomes important. AMTSL decreases the du-
ration of TSL, decreases maternal blood loss, decreases the
likelihood of uterine atony, and reduces the incidence of PPH
by approximately 65% when compared with expectant man-
agement (1,2,3,19). Therefore, the International Federation of
Gynecologists and Obstetricians, the International
Confederation of Midwives, and the World Health
Organization recommend the routine use of AMTSL for all
vaginal singleton births (20).
Active management of the third stage of labor with utero-
tonic drugs for preventing complications during the TSL is
recommended for all births (21). Oxytocin can be adminis-
tered IV or intramuscularly (IM) with fewer side effects.
Prophylactic oxytocin, at any dose, decreases the development
of uterine atony, PPH, and the need for therapeutic uterotonic
drugs (21). Therefore, oxytocin is universally recommended
as the first-line uterotonic drug of choice for the prevention of
uterine atony and related complications (8). Additionally, oxy-
tocin has a short half-life (3 minutes) and using oxytocin dur-
ing the first and second stages of labor has no effect on TSL.
Therefore, AMTSL should be recommended for all women
during vaginal delivery regardless of whether they received
oxytocin or not during the first and second stages of labor (2).
For this reason, in the present study, we did not regard the use
of oxytocin in the first and second stages of labor.
Although oxytocin could be administrated IV/IM, the most
efficient route of oxytocin administration is a slow IV infusion
or a bolus infusion given over 1–2 minutes (21,22). Oxytocin
acts quickly and effectively with minimal adverse effects and
can be used in all women, which makes it the main interven-
Table 1: Demographic characteristics of the two groups
Variables Cord drainage (n=53) Oxytocin alone (n=59) p value
Age 25.8±4.3 27±5.4 0.30a
BMI 27.7 6±3.51 28.17±3.57 0.56a
Gravity 2 (1-10) 2 (1-5) 0.79b
Parity 1 (0-4) 1 (1-3) 0.37b
Gestational ages (weeks) 39.3±1.3 39±1.5 0.29a
Birth weight (gram) 3360±370.1 3357.9±562.4 0.92a
Data presented as mean ± standard deviation or median with minimum maximum
BMI: Body mass index, a: Student t test, b: Mann-Whitney U-test
Table 2: Comparison of duration of labor stages and hemoglobin values between the two groups
Variables Cord drainage (n=53) Oxytocin alone (n=59) p value
Stage 1 (hour) 8 (2-25) 8.5 (3-22) 0.27b
Stage 2 (minute) 15 (5-90) 10 (5-120) 0.11b
Stage III (minute) 3.4(0.35-16.2) 5.10 (2.3-11) <0.01b
Hemoglobin level on admission 12.3±1.3 12.3±1.1 0.89a
Hemoglobin level at postpartum 6th hours 11.6±1.3 11.6±1.2 0,95a
Hemoglobin differences between on admission and
postpartum 6th hours (mg/dL) 0.6 (0.3-2.6) 0.6 (0.1-1.2) 0.17b
Data presented as mean ± standard deviation or median with minimum maximum values.
a: Student t test, b: Mann-Whitney U-test

Gynecology Obstetrics & Reproductive Medicine 2016;22:0 4
tion for reducing PPH and is the first uterotonic drug option
(23). The administration of oxytocin during the TSL reduces
the risk of PPH by 40% (24). Immediately after fetal delivery,
starting intravenous infusion of 20 IU of oxytocin in 500 mL
RL and given within 2 hours is the routine protocol in our in-
stitute for AMTSL. This routine protocol was administered to
both groups so as not to sustain any adverse effects of not
using an appropriate AMTSL. This may explain why PPH or
uterine atony did not develop, and the median duration of the
TSL was shorter in both groups than previously reported ex-
pectant management.
It has been reported that placental cord drainage shortens
the duration of TSLs. Giacalone et al. reported that in their
randomized control study comparing placental cord drainage
with expectant delivery of the placenta, the median TSL dura-
tion was 8 minutes in the placental cord drainage group and 15
minutes in the control group (25). Roy et al. reported that pla-
cental blood drainage during vaginal delivery shortens the du-
ration of TSL, reduces both the blood loss and the incidence
of PPH (26). Shravage et al. reported in their randomized con-
trolled study that the average TSL duration was significantly
shorter in the placental cord drainage group than in the control
group. Sharma et al. performed a randomized study in which
placental cord drainage was compared with placental cord
traction during cesarean sections. They found that placental
cord drainage shortened the TSL duration and reduced the re-
tained placenta rate (10). In another study, Sharma et al. com-
pared placental cord drainage with controlled cord traction
after the administration of 0.2 mg of ergonovine with the de-
livery of the anterior shoulder and immediate cord clamping to
compare PPH and TSL length. They reported that placental
cord drainage significantly reduces the TSL duration in vagi-
nal deliveries (11). A 2011 Cochrane review reported that pla-
cental cord drainage significantly shortens TSL and decreases
the average blood loss. The authors’ concluded that there was
a small reduction in the TSL length and in the amount of blood
loss when cord drainage was compared with no cord drainage
(27). In the present study, placental cord drainage shortened
the TSL duration. This result is in accordance with the results
from previous studies.
Herman et al. ultrasonographically demonstrated that a
retro-placental myometrial contraction is mandatory to pro-
duce shearing forces on the interface between the placenta and
the myometrium to supply placental separation (5,28).
Contractions occurring prior to delivery are insufficient to
cause placental separation since, in the presence of the fetus,
the myometrium is unable to achieve the necessary strain for
placental separation (5,28). Placental cord drainage is likely to
decrease placental volume and surface area that might facili-
tate placental separation and uterine contraction, which results
in a further increase of the separated area. This facilitates uter-
ine contraction and further placental separation, resulting in
early placental delivery and a shortening of the TSL duration.
This may explain why the TSL was shorter in the placental
cord drainage group in the current study.
Placental retention is defined as the failure of placental de-
livery within 30 to 45 minutes and it usually requires inter-
vention to assist delivery (18). Failure of the retro-placental
myometrium contraction is the usual cause of a retained pla-
centa. When the duration of a placental retention increases to
30 minutes, there is a greater risk of PPH (5). Placental cord
drainage may facilitate uterine contractions and shorten the
TSL. In the present study, there was no placental retention in
the study group, and only one in the control group, which was
expulsed with manual intervention under general anesthesia.
This may explain why the placental retention rate was de-
creased in the placental cord drainage group in both the pres-
ent study and previous studies.
Blood loss during TSL was not estimated in the present
study. In previous studies, blood losses were estimated using
difference methods. During blood collection at TSL, some
amniotic fluid might enter the collection bag, or there may be
an omission of blood that spattered on drapes and gowns.
Thus, the measurement remains open to inaccuracies that can
especially affect the measurement of lower amounts of blood
loss (17). Additionally, three guidelines from the American
College of Obstetrician and Gynecologists, the Royal College
of Obstetrician and Gynecologists, and the Society of
Obstetricians and Gynecologists of Canada comment on the
unreliability of estimated blood loss, such as using a visible
estimate or through the use of blood collection drapes (8).
Instead of attempting blood collection to measure blood
losses, we compared hemoglobin differences between the pa-
tient at admission and at their postpartum sixth hour. We know
from previous studies that shortening the TSL duration also
decreases blood loss.
The present study demonstrated that placental blood
drainage with oxytocin shortened the TSL duration compared
to oxytocin alone. Placental blood drainage is simple, does not
introduce any additional cost, and can be performed by any
birthing attendant. It might be used alone where uterotonic
agents were not available or combined with oxytocin for
AMTSL in low-risk vaginal deliveries. Because of the small
sample size, this study is limited in its ability to derive a de-
finitive result and generalize the results to the entire popula-
tion. Furthermore, well-randomized studies with large sample
sizes are needed to evaluate the effectiveness of placental cord
drainage with IV oxytocin administration in the TSL.
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