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Neurodevelopmental outcome at the age of 4 years according
to the planned mode of delivery in term breech presentation :
a nationwide, population-based record linkage study
Macharey, Georg
2018-04
Macharey , G , Väisänen-Tommiska , M , Gissler , M , Ulander , V-M , Rahkonen , L , Nuutila
, M & Heinonen , S 2018 , ' Neurodevelopmental outcome at the age of 4 years according to
the planned mode of delivery in term breech presentation : a nationwide, population-based
record linkage study ' , Journal of Perinatal Medicine , vol. 46 , no. 3 , pp. 333-339 . https://doi.org/10.1515/jpm-2017-0127
http://hdl.handle.net/10138/243953
https://doi.org/10.1515/jpm-2017-0127
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J. Perinat. Med. 2018; 46(3): 333–339
Georg Macharey*, Mervi Väisänen-Tommiska, Mika Gissler, Veli-Matti Ulander, Leena Rahkonen,
Mika Nuutila and Seppo Heinonen
Neurodevelopmental outcome at the age of 4years according
to the planned mode of delivery in term breech presentation:
anationwide, population-based record linkage study
https://doi.org/10.1515/jpm-2017-0127
Received April 18, 2017. Accepted July 25, 2017. Previously published
online September 9, 2017.
Abstract
Purpose: To evaluate whether a trial of planned vaginal
breech labor affects neurologic development in children.
Methods: This is a nationwide, Finnish, population-based
record linkage study. An odds ratio with 95% confidence
intervals was used to estimate the relative risk that a
child delivered by planned vaginal breech labor would
be diagnosed with adverse neurodevelopmental outcome
( cerebral palsy, epilepsy, intellectual disability, sensor
neural developmental outcome, hyperactivity, speech and
language problems) at the age of 4 years. The reference
group were children born by planned cesarean section.
Results: During a study period of 7years, 8374 infants were
delivered in breech position. Among them, 3907 (46.7%) had
an attempted labor and 4467 (53.3%) infants were delivered
by planned cesarean section. There were no differences in
the neurodevelopmental outcome. In the planned vaginal
labor group, 133 (3.4%) children had an abnormal neurode-
velopmental outcome at the age of 4 years compared to 142
(3.2%) in the planned cesarean section group.
Conclusion: The absolute risk of abnormal neurological
outcome in breech deliveries at term was low, regardless
of planned mode of birth. Planned vaginal breech labor
did not increase the risk for abnormal neurological out-
come compared to planned cesarean section.
Keywords: Adverse perinatal outcome; breech delivery;
cerebral palsy; epilepsy; neonatal morbidity; neurodevel-
opmental outcome.
Introduction
Breech presentation at term occurs in 2%–3% of all single-
ton pregnancies [1–3]. Neonates born vaginally in breech
position at term have been reported to have a higher
perinatal morbidity and mortality rate [4, 5]. Several
studies have been conducted to determine whether
vaginal breech delivery at term is safe for the mother and
the child in settings where women have been carefully
selected and labor management takes place in an ade-
quate obstetric facility [6–8]. The effect of vaginal breech
labor on the neonate’s long-term neurodevelopment is
unclear, since some studies, but not all, have shown an
association between vaginal breech delivery and cerebral
palsy, epilepsy or a low examination achievement [9–15].
Few studies have shown that cesarean section reduces
long-term adverse outcome [11, 16]. On the other hand,
some data have shown that adverse neonatal long-term
outcome was not related to intrapartum events [17–20],
but to obstetric risk factors, which are known to be asso-
ciated with breech presentation at term [17, 18]. The aim
of the present study was to determine whether a trial of
singleton vaginal breech labor at term is associated with
an adverse neurodevelopmental outcome in children at
the age of 4years.
Methods
Study design and data sources
We conducted a population-based, record linkage study, using the
National Medical Birth Register and the hospital discharge register,
maintained by the National Institute for Health and Welfare. The data
for the National Medical Birth Register are collected by all maternity
hospitals in Finland. It collects baseline data on pregnancies, deliv-
eries, and the newborn’s outcome during the first days of life, by
using the maternal prenatal records. Reporting to the National Medi-
cal Birth Register is obligatory. The data include all live births and
stillbirths with a birth weight of 500 g or beyond or with a gestational
age of 22weeks or older. Less than 0.1% of the data concerning all
newborns is missing, but missing data are supplemented by the cen-
tral population register for live births and the cause of death register
for stillbirths and neonatal deaths. The hospital discharge register
*Corresponding author: Georg Macharey, MD, Department of
Obstetrics and Gynecology, Helsinki University Hospital, University
of Helsinki, Haartmaninkatu 2, Helsinki 00029 HUS, Finland,
E-mail: georg.macharey@hus.fi
Mervi Väisänen-Tommiska, Veli-Matti Ulander, Leena Rahkonen,
Mika Nuutila and Seppo Heinonen: Department of Obstetrics and
Gynecology, Helsinki University Hospital, University of Helsinki,
Helsinki, Finland
Mika Gissler: National Institute for Health and Welfare (THL),
Helsinki, Finland
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Macharey etal., Neurodevelopmental outcome in breech children
contains information on all inpatient periods in all Finnish hospitals
and all outpatient visits. The collected information includes demo-
graphic data, maternal information before and after the delivery,
data regarding intrapartum procedures and complications, as well as
neonatal outcome. The information is coded according to the Inter-
national Statistical Classification of Diseases and Related Health
Problems 10
th
Revision (ICD-10).
We used anonymized data of the mothers and infants recorded
on the National Medical Birth Register and the hospital discharge
register for this study. Authorization to use the data was obtained
from the National Institute for Health and Welfare as required by the
national data protection legislation law in Finland (Reference num-
ber THL/1200/5.05.00/2012).
Study population
The studied population included all breech deliveries from January
1, 2004, to December 31, 2010. Exclusion criteria were multiple
gestations, preterm deliveries, infants with intrauterine growth
restrictions (defined as birth weight <2SD), infants with congenital
malformations and pregnancies with a placental abruption (ICD-
10 code O45.-). Comparisons were made between children born by
planned cesarean section and children born vaginally or by emer-
gency cesarean section after a trial of labor. Criteria used for a trial
of vaginal breech delivery in Finland are based on International
Obstetrics and Gynecology Guidelines [21–23]. These criteria include:
(a) the mother is motivated to deliver vaginally; (b) adequate mater-
nal pelvis confirmed by magnetic-resonance pelvimetry (obstetrical
conjugata vera >11.5 cm, interspinous diameter >10 cm, diameter
transversa >12.5cm); (c) estimated fetal weight is <4000 g evaluated
by ultrasound; (d) fetus is in frank, complete or incomplete breech
position with the head in flexed position; (e) fetus does not suer
from intrauterine growth restrictions; (f) absence of fetal anomaly
that may cause dystocia. All breech deliveries are handled or guided
by a consultant and occur in a hospital with access to emergency
cesarean section.
A comparison of outcomes was made between planned cesarean
deliveries and planned vaginal deliveries. Planned cesarean delivery
was defined as an elective cesarean delivery in mothers where cesar-
ean delivery was planned. Planned vaginal delivery comprised cases
with spontaneous or induced start of delivery regardless of cesarean
delivery along the course of delivery. The intended mode of delivery
was collected from the maternal records.
Outcomes
The main outcome was adverse neurodevelopment in children at the
age of 4years. Neurodevelopment outcome includes cerebral palsy,
epilepsy, intellectual disability and sensor neural defects, including
visual impairment and deafness, speech or language problems and
hyperactivity. These data were received from the hospital discharge
register using the ICD-10 (1996–2008) codes for neurologic diagno-
ses (Table1). In Finland, the diagnosis of cerebral palsy, epilepsy,
autism, intellectual disability, sensor neural defects, speech or
language problems and hyperactivity is based on medical history,
ultrasonography, and MRI data as required, and multidisciplinary
evaluations in secondary or tertiary pediatric neurology units.
Cerebral palsy is usually evident within the first 2years of life and
practically always by the age of 3–4years [24]. The diagnosis of cer-
ebral palsy is added to the hospital discharge register immediately
after diagnosis. The Finnish public health care system calls for all
children to undergo annual physical examinations; thus, the neuro-
logic diagnoses are consistently recognized by the age of 4 years [25].
The following covariates were collected from the medical birth reg-
ister: umbilical artery pH, 5-min Apgar score <7, nulliparity, mater-
nal age, smoking, gestational age at delivery, gestational diabetes,
diabetes mellitus type I, preeclampsia, neonatal sex (male), birth
weight, infertility, history of cesarean section and body mass index
(BMI) >30.
Statistical analysis
Statistical differences in categorical variables were evaluated with
the χ
2
-test and differences in continuous variables by the Mann-
Whitney U-test as appropriate. Characteristics of the children
and their mothers were given as means with standard deviation
score (SDs) in case of normally distributed continuous variables,
by medians with interquartile range in skewed distributed vari-
ables, and by number of values as percentages if variables were
categorical. Differences were deemed to be significant if P < 0.05.
In addition, we calculated odds ratios (OR) with 95% confidence
intervals (CI) as estimates of the relative risk that a neonate with
a planned vaginal breech labor would be diagnosed with adverse
neurodevelopmental outcome, using neonates with planned
cesarean section as mode of delivery as the reference group. For
the assessment of possible confounders, we used multivariate
analysis. The data were analyzed using SPSS for Windows V.19.0
( Chicago, IL, USA). The reporting of this study conforms to the
STROBE statement [26].
Results
During the study period covering 7 years, 415,526 deliv-
eries were observed. After the exclusion of stillbirths,
preterm pregnancies, multiple gestations, infants with
congenital malformations or intrauterine growth restric-
tions and deliveries with placental abruption, 356,010
Table 1:Diagnose codes for adverse neurological outcome.
ICD- code
Cerebral palsy G .-, G.-, G.- G.-
Epilepsy G.-
Intellectual disability F.-, F.-, F.-, F.-,
F.-, F.-, F.-
Autism F.-
Speech or language problems F.-
Visual defects H.-
Auditory defects H.-
Hyperactivity F.-
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335
deliveries were analyzed. Of these, n = 8374 (2.4%) infants
were delivered in breech position. Among them, 4467
(53.3%) infants were delivered by planned cesarean
section. The trial of vaginal labor group consisted of 3907
(46.7%) attempted labors, of which 1723 (44.1%) deliveries
had an intrapartum cesarean section (Figure1).
Of all analyzed children born in breech presentation,
a total of 275 (3.3%) suffered from an abnormal neuro-
development at the age of 4 years. Of all children deliv-
ered vaginally or by emergency cesarean section 133
(3.4%) suffered from an abnormal neurodevelopment
at the age of 4 years compared to 142 (3.2%) infants
delivered by planned cesarean section [OR 1.06; 95% CI
(0.74–1.52)].
Five children in the planned vaginal labor group had
cerebral palsy, compared to six in the planned cesarean
section group [OR 1.31; 95% CI (0.28–6.07)]. Epilepsy was
diagnosed among 23 children in the planned vaginal labor
group (0.59%) and in 23 in the planned cesarean section
group (0.51%) [OR 1.39; 95% CI (0.62–3.14)]. No signifi-
cant difference was found between vaginal breech labors
and planned cesarean sections for the other variables of
abnormal neurodevelopment either (Table2).
Table3 shows the demographics, pregnancy charac-
teristics and reproductive factors of both groups. Signifi-
cantly more infants born after a trial of vaginal delivery
had an arterial pH below 7.0 (1.2 vs. 0.1%) and a 5-min
Apgar below 7 (3.1 vs. 1.2%) than those born by planned
cesarean section. The prevalence of perinatal mortality
in planned vaginal breech delivery did not differ signifi-
cantly from planned cesarean breech delivery (3 children
[0.08%] vs. 0 children [0%]) (Table3).
Deliveries 2004–2010
n
=
415,526
Singleton fetuses at term
n
=
356,010
Breech presentation
n
=
8374
Trial of vaginal breech delivery
n
=
3907
Vaginal breech delivery
n
=
2184
Converted deliveries to
cesarean section
n
=
1723
Planned cesarean section
n
=
4467
Cephalic presentation
n
=
347,636
Excluded:
Multiple gestations
Preterm deliveries
Congenital malformations
IUGR´s
Placental abruptions
Figure 1:Flow of deliveries through the study period.
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Macharey etal., Neurodevelopmental outcome in breech children
Discussion
Our study shows that a trial of vaginal breech delivery is
not associated with adverse neurological development in
children at the age of 4 years, if conducted in women with
a low-risk breech pregnancy (exclusion of cases with fetal
growth restriction, congenital anomalies and placental
abruption) and managed in a modern obstetric setting.
The children born vaginally in breech position were as
healthy as the children born by planned cesarean section
at the age of 4years. Vaginal labor was not associated with
cerebral palsy, epilepsy, intellectual disability, autism,
speech or language problems, visual or auditory defects
or hyperactivity.
Adverse neurodevelopmental outcome like cerebral
palsy can be caused by preconceptional factors (both
Table 2:Crude and adjusted odds ratio (OR) with 95% confidence intervals (CI) for neurodevelopment among singletons born in breech
position at term.
Planned vaginal
labor (n=)
Planned cesarean
section (n=)
OR (% CI) Adjusted
b
OR
(% CI)
n % n %
Cerebral palsy . . . (.–.) . (.–.)
Epilepsy . . . (.–.) . (.–.)
Intellectual disability . . . (.–.) . (.–.)
Autism . . . (.–.) . (.–.)
Speech or language problems . . . (.–.) . (.–.)
Visual defects . . . (.–.) . (.–.)
Auditory defects . . . (.–.) . (.–.)
Hyperactivity . . . (.–.) . (.–.)
Combined adverse outcome
a
. . . (.–.) . (.–.)
a
Infants with more than one diagnosis.
b
Adjusted for umbilical artery pH, 5-min Apgar score <7, nulliparity, maternal age, smoking, gestational age at delivery, gestational
diabetes, diabetes mellitus type I, preeclampsia, neonatal sex (male), birth weight, infertility, history of cesarean section and body mass
index (BMI) >30.
Table 3:Neonatal baseline characteristics of singletons born in breech position at term according to mode of delivery.
Planned vaginal
labor(n=)
Planned cesarean
section (n=)
P-value
Maternal age (years), mean±SD . . . . <.
Nulliparous . . <.
Smoking . . .
Diabetes mellitus type I . . . <.
BMI > . . .
History of cesarean section . . <.
Assisted reproduction technology . . .
Gestational diabetes . . .
Oligohydramnios . . .
Preeclampsia . . .
Gestational age at delivery, mean±SD . . . . <.
Emergency cesarean section . – –
Birth weight (g)±SD <.
Neonatal sex (male) . . .
Umbilical artery pH, mean±SD . . . . <.
Umbilical artery pH <. . . <.
-min Apgar score < . . <.
Perinatal mortality –days . .
Child mortality –days . . .
Values are n and %, unless indicated otherwise.
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