The application of the ICD-10 for antepartum stillbirth patients in a referral centre of Eastern China: a retrospective study from 2015 to 2022

Abstract

Background
The causes of some stillbirths are unclear, and additional work must be done to investigate the risk factors for stillbirths.

Objective
To apply the International Classification of Disease-10 (ICD-10) for antepartum stillbirth at a referral center in eastern China.

Methods
Antepartum stillbirths were grouped according to the cause of death according to the International Classification of Disease-10 (ICD-10) criteria. The main maternal condition at the time of antepartum stillbirth was assigned to each patient.

Results
Antepartum stillbirths were mostly classified as fetal deaths of unspecified cause, antepartum hypoxia. Although more than half of the mothers were without an identified condition at the time of the antepartum stillbirth, where there was a maternal condition associated with perinatal death, maternal medical and surgical conditions and maternal complications during pregnancy were most common. Of all the stillbirths, 51.2% occurred between 28 and 37 weeks of gestation, the main causes of stillbirth at different gestational ages also differed. Autopsy and chromosomal microarray analysis (CMA) were recommended in all stillbirths, but only 3.6% received autopsy and 10.5% underwent chromosomal microarray analysis.

Conclusions
The ICD-10 is helpful in classifying the causes of stillbirths, but more than half of the stillbirths in our study were unexplained; therefore, additional work must be done. And the ICD-10 score may need to be improved, such as by classifying stillbirths according to gestational age. Autopsy and CMA could help determine the cause of stillbirth, but the acceptance of these methods is currently low.

Full text

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Feng et al. BMC Pregnancy and Childbirth (2024) 24:164
https://doi.org/10.1186/s12884-024-06313-5 BMC Pregnancy and Childbirth
*Correspondence:
Chuan-Shou Feng
801sss@163.com
1Obstetrical department, Changzhou Women and Children Health
Hospital, Nanjing Medical University, Changzhou, Jiangsu, China
Abstract
Background The causes of some stillbirths are unclear, and additional work must be done to investigate the risk
factors for stillbirths.
Objective To apply the International Classication of Disease-10 (ICD-10) for antepartum stillbirth at a referral center
in eastern China.
Methods Antepartum stillbirths were grouped according to the cause of death according to the International
Classication of Disease-10 (ICD-10) criteria. The main maternal condition at the time of antepartum stillbirth was
assigned to each patient.
Results Antepartum stillbirths were mostly classied as fetal deaths of unspecied cause, antepartum hypoxia.
Although more than half of the mothers were without an identied condition at the time of the antepartum stillbirth,
where there was a maternal condition associated with perinatal death, maternal medical and surgical conditions
and maternal complications during pregnancy were most common. Of all the stillbirths, 51.2% occurred between
28 and 37 weeks of gestation, the main causes of stillbirth at dierent gestational ages also diered. Autopsy and
chromosomal microarray analysis (CMA) were recommended in all stillbirths, but only 3.6% received autopsy and
10.5% underwent chromosomal microarray analysis.
Conclusions The ICD-10 is helpful in classifying the causes of stillbirths, but more than half of the stillbirths in our
study were unexplained; therefore, additional work must be done. And the ICD-10 score may need to be improved,
such as by classifying stillbirths according to gestational age. Autopsy and CMA could help determine the cause of
stillbirth, but the acceptance of these methods is currently low.
Keywords International classication of diseases, Antepartum stillbirth, Causes of stillbirth, Retrospective study,
Autopsy, Chromosomal microarray analysis
The application of the ICD-10 for antepartum
stillbirth patients in a referral centre of Eastern
China: a retrospective study from 2015
to 2022
Chuan-ShouFeng1*, Shu-FenLi1 and Hui-HuiJu1
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Feng et al. BMC Pregnancy and Childbirth (2024) 24:164
Background
Stillbirth is usually dened as death after 20 weeks of
pregnancy in most developed countries and after 28
weeks of pregnancy in developing countries, before com-
plete expulsion or extraction from the mother of a prod-
uct of conception, which is indicated by the fact that after
such separation, the fetus does not show any evidence of
life [1, 2]. In China, stillbirth is dened as the death of a
fetus after 20 weeks of gestation.
Stillbirth is a serious adverse pregnancy outcome and
a common global public health problem. e global
stillbirth rate is estimated to be 18·4 per 1000 births [3].
Globally, each year, approximately 2·6million stillbirths
occur, 99% of which occur in low- and middle-income
countries (LMICs) [3–6]. Studies have shown that still-
born infants are more likely to be antepartum, with only
a few of the deaths occurring intrapartum. In United
Kingdom, 48·3% of stillbirths occur during the antepar-
tum period [7]. Irisa Zile et al. [8] reported that 73.5% of
stillborn neonates were antepartum. In 2016, approxi-
mately 90% of cases occurred before labor started in
Sweden [9]. Based on the Every Newborn Action Plan to
improve newborn health and prevent stillbirths, a still-
birth target of 12 or less stillbirths per 1000 total births
for all countries by 2030 was set, with a focus on address-
ing inequalities and the use of audit data to track and pre-
vent stillbirths [10].
However, current researches on the causes of stillbirths
are insucient, and many stillbirths are of unknown
cause, especially there is little research published on dif-
ferences in maternal and fetal characteristics associated
with antepartum stillbirth. So, more work must be done
to investigate the risk factors for stillbirths, to determine
which are preventable, and to provide the right advice to
parents after stillbirths and help them build their future
pregnancy plans.
e classication system helps to divide the causes of
stillbirth into relevant groups to assist in counselling and
the development of family planning. A number of clas-
sication systems have been applied to stillbirth in dif-
ferent countries [11, 12], however, global comparisons
are dicult because of the multiple classication systems
used for perinatal death [12, 13]. Better classication sys-
tems are needed to achieve accuracy and consistency in
the reporting of causes of stillbirths.
e World Health Organization adapted the exist-
ing International Classication of Diseases, tenth
revision (ICD-10), for perinatal death as a globally
applicable and comparable system in 2016 [14], the new
International Classication of Diseases for Perinatal
Mortality (ICD-PM) classication system uses stratica-
tion to further determine the causes of fetal death and/
or contributing maternal conditions. e ICD-PM has
three distinct features. It identies the timing of perinatal
death (antepartum, intrapartum, neonatal); the causes of
death linked to existing ICD codes are logically grouped;
and ICD-PM links the maternal condition with the peri-
natal death. is new classication system will contribute
to more accurate and uniform reporting for comparison
in various situations.
In this study, we evaluated the current status of ante-
partum stillbirths in a referral center of eastern China
using the International Classication of Diseases (ICD-
10) to classify the causes of stillbirths and determine
relevant preventive measures. At the same time, the fre-
quency of autopsy and chromosomal microarray analysis
in stillbirth cases was investigated.
Methods
is retrospective study was conducted at Changzhou
Women and Children Health Hospital aliated to Nan-
jing Medical University. Changzhou is a city of more than
5 million people in China’s developed eastern coastal
region, and our hospital is the only tertiary hospital of
obstetrics and gynecology; it is the only regional high-
risk maternal treatment center and prenatal diagnosis
center in the region, with 1,000 beds, and in 2022, 9896
deliveries.
All patients with antepartum stillbirths at Chang-
zhou Women and Children Health Hospital aliated to
Nanjing Medical University from January 2015 through
December 2022 were included in this study. Antepartum
stillbirths were dened as fetal death occurring after 20
completed weeks of gestation. or birthweight ≥ 350 g if
gestational age is unknown.
e data were extracted from outpatient obstetric
examination records, hospital admissions and deliv-
ery registers. e placentas of all antepartum stillbirths
were routinely pathologically examined, autopsies and
chromosomal microarray analysis (CMA) were recom-
mended for all patients. If the parents refused, the rea-
sons for refusal were inquired in detail and recorded.
Stillbirths are serious complications in obstetrics, and we
attach great importance to every case of stillbirth. So, in
our hospital, it is routine to discuss every case of stillbirth
to nd the cause of stillbirth as much as possible. Multi-
disciplinary meetings with doctors, nurses, and midwives
from the hospital were conducted to identify the most
likely cause of fetal death as well as other contributing
maternal conditions via consensus. e causes of ante-
partum stillbirths were analyzed with respect to clinical
information and classied according to ICD-10. Antepar-
tum stillbirths were further classied into the six ICD-
PM sub-categories (A1 to A5, with A6 representing cause
unknown). e contributing maternal conditions were
classied into ve major categories (M1 to M4, with M5
representing the unknown cases) [14] (Table1). Gesta-
tional age was determined mainly by the nal menstrual
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Feng et al. BMC Pregnancy and Childbirth (2024) 24:164
period or ultrasound results in early pregnancy if the ges-
tational age did not match.
Data analysis
Descriptive analyses were conducted using SPSS. Simple
statistical tests using absolute numbers were used to cal-
culate percentages.
Results
From January 2015 through December 2022, a total of
87,588 women gave birth in Changzhou Women and
Children Health Hospital aliated to Nanjing Medical
University, of which we reviewed data on a total of 420
(0.48%) antepartum stillbirths. Table2 maps the demo-
graphic and clinical characteristics of women who expe-
rienced a stillbirth. Among the patients, 248 (59·0%) were
primipara and 172 (41·0%) were multigravida. In addi-
tion, 173 (41.2%) were from urban areas and 247 (58.8%)
from rural areas. Data on maternal ages and gestational
ages were tested to have a normal distribution. e aver-
age age of the women who had stillbirth were 28·99 ± 5·38
(17–44) years, with a median of 28 years, and the aver-
age gestational age were 30.06 ± 5·74 (20–41) weeks, with
a median was 30 weeks.
Table3 maps the causes of stillbirth against the mater-
nal conditions for all antepartum stillbirths using the
ICD-PM. Antepartum stillbirths were mostly classied
as fetal deaths of unspecied causes (n = 235, 56.0%),
fetal anomalies and chromosomal abnormalities (n = 49,
11.7%), or other specied antepartum disorder (n = 45,
10.7%). In contrast, more than half (55·9%) of mothers
were without an identied condition in the antepartum
stillbirths, and only 44·1% of antepartum deaths could be
classied into one of the groups for associated maternal
condition. M4 (Maternal medical and surgical condi-
tions) contributed the highest proportion (n = 67, 16.0%).
e annual incidence of antepartum stillbirths is shown
in Fig.1. From 2015 to 2022, there was a marked decline
in the incidences of antepartum stillbirths. At the same
time, the proportion of stillbirths without regular obstet-
ric examination among all antepartum stillbirths had
decrease year by year (Fig.2). Among all the cases of still-
births in 2015, we found that the proportion of patients
without regular obstetric examination was relatively high,
up to 70·4%. However, in 2022, the proportion fell to
21.7%.
Figure3 shows the percentage of causes of stillbirths by
gestational age, in which more than half (51.2%) of still-
births occurred between 28 and 37 weeks of gestation,
and nearly one third occurred before 28 weeks of gesta-
tion, and only 16.0% occurred after 37 weeks of gestation.
In addition, the main causes of stillbirths vary with gesta-
tional age. e main causes of stillbirths before 28 weeks
of gestation were unspecied causes, fetal anomalies and
Table 1 ICD-PM categories with description and exemplar-specic causes
Category Description Examples
Antepartum stillbirths A1 Congenital malformations and
chromosomal abnormalities
Anencephaly, encephalocele, microcephaly, congenital hydrocephalus, spina bida, etc.
A2 Infection Congenital syphilis, congenital malaria, congenital rubella syndrome, congenital TB, etc.
A3 Antepartum hypoxia Intrauterine hypoxia.
A4 Other specied antepartum disorder Vasa previa, ruptured cord, twin-twin transfusion, Intraventricular (nontraumatic)
haemorrhage, Rhesus and ABO isoimmunization, etc.
A5 Disorders related to fetal growth Small for gestational age, macrosomia, post-term, etc.
A6 Antepartum death of unspecied cause Intrauterine death of unspecied cause
Maternal
conditions
M1 Complications of placenta, cord and membranes Abruptio placentae, prolapsed cord, chorioamnionitis, etc.
M2 Maternal complications of pregnancy Premature rupture of membranes, oligo- and polyhydramnios, ectopic pregnancy, multiple
pregnancy, etc.
M3 Other complications of labour and delivery Breech delivery and extraction, forceps delivery, Caesarean delivery.
M4 Maternal medical conditions hypertensive disorders, maternal injury, maternal use of tobacco, alcohol or drugs, etc.
M5 No maternal conditions No condition identied.
https://doi.org/10.1371/journal.pone.0215864.t001
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Feng et al. BMC Pregnancy and Childbirth (2024) 24:164
Table 2 Demographic and clinical characteristics of women who experienced a stillbirth at the Changzhou Women and Children Health Hospital, 2015–2022
Characteristics 2015
n = 125%)
2016
n = 75(%)
2017
n = 69(%)
2018
n = 33(%)
2019
n = 47(%)
2020
n = 25(%)
2021
n = 23(%)
2022
n = 23(%)
Total
n = 420(%)
Maternal age
(years)
< 18 2(1.6) 0(0。0) 0(0.0) 0(0.0) 0(0.0) 0(0.0) 0(0.0) 1(4.4) 3(0.7)
18–35 105(84.0) 62(82.7) 61(88.4) 28(84.8) 43(91.5) 22(88.0) 18(78.3) 19(82.6) 358(85.2)
> 35 18(14.4) 13(17.3) 8(11.6) 5(15.2) 4(8.5) 3(12.0) 5(21.7) 3(13.0) 59(14.1)
Gestational age
at birth
< 28 49(39.2) 34(45.3) 28(40.6) 11(33.3) 16(34.1) 0(0.0) 0(0.0) 0(0.0) 138(32.8)
28–37 59(47.2) 29(38.7) 30(43.5) 20(60.6) 26(55.3) 17(68.0) 17(73.9) 17(73.9) 215(51.2)
> 37 17(13.6) 12(16.0) 11(15.9) 2(6.1) 5(10.6) 8(32.0) 6(26.1) 6(26.1) 67(16.0)
Parity Primipara 79(63.2) 41(54.7) 41(59.4) 18(54.5) 30(63.8) 11(44.0) 11(47.8) 16(69.6) 248(59.0)
Multipara 46(36.8) 34(45.3) 28(50.6) 15(45.5) 17(36.2) 14(56.0) 12(52.2) 7(30.4) 172(41.0)
Regular check-ups yes 37(29.6) 35(46.7) 33(47.8) 17(51.5) 25(53.2) 17(68.0) 16(69.6) 18(78.3) 198(47.1)
no 88(70.4) 40(53.3) 36(52.2) 16(48.5) 22(46.8) 8(32.0) 7(30.4) 5(21.7) 222(52.9)
Residence Urban areas 43(34.4) 19(25.3) 19(27.5) 16(48.5) 21(44.7) 17(68.0) 19(82.6) 19(82.6) 173(41.2)
Rural areas 82(65.6) 56(74.7) 50(72.5) 17(51.5) 26(55.3) 8(32.0) 4(17.4) 4(17.4) 247(58.8)
Type of
Pregnancy
Singleton 122(97.6) 71(94.7) 66(95.7) 33(100.0) 46(97.9) 24(96.0) 23(100.0) 23(100.0) 408(97.1)
Multiple 3(2.4) 4(5.3) 3(4.3) 0(0.0) 1(2.1) 1(4.0) 0(0.0) 0(0.0) 12(2.9)
BMI (kg/m2)< 28 103(82.4) 58(77.3) 47(68.1) 26(78.8) 35(74.5) 19(76) 19(82.6) 17(73.9) 324(77.1)
≥ 28 22(17.6) 17(22.7) 22(31.9) 7(21.2) 12(25.5) 6(24) 4(17.4) 6(26.1) 96(22.9)
Fetal sex Male 61(48.8) 39(52) 37(53.6) 14(42.4) 22(46.8) 14(56) 11(47.8) 10(43.5) 208(49.5)
Female 64(51.2) 36(48) 32(46.4) 19(57.6) 25(53.2) 11(44) 12(52.2) 13(56.5) 212(50.5)
Autopsy yes 1(0.8) 1(1.3) 2(2.9) 1(3.0) 3(6.4) 1(4.0) 3(13.0) 3(13.0) 15(3.6)
no 124(99.2) 74(98.7) 67(97.1) 32(97.0) 44(93.6) 24(96.0) 20(87.0) 20(87.0) 405(96.4)
CMA yes 0(0.0) 5(6.7) 3(4.3) 6(18.2) 12(25.5) 6(24.0) 5(21.7) 7(30.4) 44(10.5)
no 125(100.0) 70(93.3) 66(95.7) 27(81.8) 35(74.5) 19(76.0) 18(78.3) 16(69.6) 376(89.5)
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Feng et al. BMC Pregnancy and Childbirth (2024) 24:164
chromosomal abnormalities and other specied antepar-
tum disorder. e main causes of stillbirths between 28
and 37 weeks of gestation and after 37 weeks of gesta-
tion were all unspecied causes, antepartum hypoxia and
other specied antepartum disorder.
Autopsy and chromosomal microarray analysis (CMA)
were recommended for all stillbirths, but only 3.6%
of patients underwent autopsy, and 10.5% underwent
chromosomal microarray analysis. e autopsy of 15
patients revealed 5 abnormalities: 1 abnormal lung devel-
opment, 1 cardiac malformation, 1 digestive system mal-
formation,1 agenesis of corpus callosum, and 1 pleural
eusion. Six abnormalities were found in the 44 patients
according to chromosomal microarray analysis: 2 trisomy
13, 3 trisomy 18, and 1 trisomy 21.
Table 3 The causes of stillbirth against the maternal conditions for all antepartum stillbirths using the ICD-PM.
Maternal condition M1 M2 M3 M4 M5 Total (%)
Antepartum stillbirths
A1 11 4 10 15 9 49 (11.7)
A2 14 5 0 5 2 26 (6.2)
A3 7 6 3 16 3 35 (8.3)
A4 11 15 9 7 3 45 (10.7)
A5 3 8 3 15 1 30 (7.1)
A6 18 13 2 9 193 235 (56.0)
Total (%) 64 (15.2) 51(12.1) 27 (7.7) 67 (16.0) 211 (55.9) 420(100.0)
Fig. 2 The proportion of without regular obstetric examination (%)
Fig. 1 The incidences of antepartum stillbirths in the eight years (%)
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Feng et al. BMC Pregnancy and Childbirth (2024) 24:164
We thoroughly investigated the reasons why parents
refused these two examinations. Of the 405 stillbirths in
which autopsies were refused, 21 parents refused to par-
ticipate in the survey, and 384 parents participated and
completed the survey. e main reasons for refusing
autopsies were: the traditional concept of preserving the
integrity of the body after death (46·9%), no planning for
another pregnancy (18·8%), the invasiveness of the autop-
sies (12·1%) (Fig.4). Of the 323 stillbirths in which CMA
were refused, 19 parents refused to participate in the
survey, and 357 parents participated and completed the
survey. e main reasons for rejecting CMA were: lack
of understanding of CMA (39·3%), high costs (23·4%), no
planning for another pregnancy (18·2%) (Fig.5).
Discussion
Main ndings
We demonstrated the application of the ICD-10 for
evaluating antepartum stillbirths. In our study, we found
that antepartum stillbirths were mostly classied as
fetal deaths of unspecied causes, fetal anomalies and
chromosomal abnormalities, or other specied antepar-
tum disorder. More than half of these stillbirths are of
unspecied cause; therefore, additional studies must be
performed to address this problem. Although more than
half of mothers were without an identied condition at
the time of the antepartum stillbirth, where there was
a maternal condition associated with perinatal deaths,
maternal medical and surgical conditions and maternal
complications during pregnancy were most common.
erefore, early detection of pregnancy complications
and complications and standardized management and
treatment were very important for reducing the inci-
dence of stillbirth caused by these factors.
In the last eight years, the proportion of patients
without regular obstetric examination has been on the
decline due to the extensive publicity of the importance
of obstetric examinations and the strengthening of out-
patient management since 2016.
Of all the stillbirths, 32.8% occurred before 28 weeks
of gestation, 51.2% occurred between 28 and 37 weeks
of gestation, and 15.9% occurred after 37 weeks of ges-
tation. e main causes of stillbirths at dierent gesta-
tional ages also diered. e main causes of stillbirths
before 28 weeks of gestation were unspecied causes
and fetal anomalies and chromosomal abnormalities.
e main causes between 28 and 37 weeks of gestation
were: unspecied causes and antepartum hypoxia. e
main causes after 37 weeks of gestation were: unspecied
causes and antepartum hypoxia. erefore, for stillborn
patients of dierent gestational ages, dierent counter-
measures may need to be taken.
e main reasons for refusing autopsies were the tra-
ditional concept of preserving the integrity of the body
Fig. 3 The percentage of the causes of stillbirths at dierent gestational ages
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Feng et al. BMC Pregnancy and Childbirth (2024) 24:164
after death, no planning for another pregnancy and the
invasiveness of the autopsy. e main reasons for reject-
ing CMA were lack of understanding of CMA, high costs
and no planning for another pregnancy.
Strengths and limitations
In this study, we retrospectively analyzed stillbirth
patients in the last 8 years, and the number of cases was
relatively sucient, which can reect some problems
to a certain extent. However, considering that this was
a retrospective study, it was not conducted using the
same standardized instructions, which may have aected
the coding. We are unable to comment on the extent to
which each prenatal stillbirth was investigated.
Interpretation in light of previous research
Although many interventions have been implemented
in many countries, stillbirths remain a major global pub-
lic health problem. In many countries, stillbirths cause
great pain for parents [15, 16]. Although the stillbirth rate
decreased by 19.4% from 2000 to 2015 [5, 17], follow-
ing various interventions worldwide, the global stillbirth
rate was still as high as 18·4 per 1,000 births in 2015, or
2·6 million per year [3]. Moreover, the global stillbirth
rate is extremely uneven, with 99% of these deaths occur-
ring in low - and middle-income countries [3–6]. e rate
of stillbirth in poor communities is likely to be two or
more times greater than that in wealthier areas [18, 19].
e rate of stillbirths in UK was 4·2 per 1,000 [20], and
Singapore and Finland had the lowest rates of stillbirths,
at 2·0 per 1,000 [21]. However, in sub-Saharan Africa, it
was 32·2 per 1,000 [15]. In our study, we found that the
average stillbirth rate was 4.8 per 1000 in the last eight
years and 2.3 per 1000 in 2022, was similar to what was
observed in developed countries. However, we counted
only antepartum stillbirths, the rate of stillbirths will be
higher if we included intrapartum stillbirths and neona-
tal deaths. Given that the stillbirth rate was related to the
state of the economy, the stillbirth rate was likely to be
higher in less developed parts of China.
Stillbirths are very unfortunate events, and more wor-
ryingly, women who experienced a stillbirth are more
likely to suer the same outcome in later pregnancies
[22]. erefore, determining the cause of stillbirth is
important and can help provide correct advice to parents
about stillbirths and help them plan future pregnancies.
A meta-analysis and literature review revealed that pri-
miparity was an important risk factor for stillbirth [23].
In our study, nearly 60% of stillbirths were primipara,
which prompted us to pay attention to this issue. At the
same time, we also found that 59.0% of stillbirths were
from rural areas, which is consistent with the ndings of
previous studies [23, 24]. ere is often a lack of health
awareness and low socioeconomic status in most rural
Fig. 4 The reasons for refusing autopsies
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Feng et al. BMC Pregnancy and Childbirth (2024) 24:164
areas; therefore, women in these areas are more likely to
experience stillbirth.
In our study, we found that the main causes of ante-
partum stillbirths were unspecied causes, antepartum
hypoxia, and other specied antepartum disorder. How-
ever, in South Africa and the United Kingdom [7], the
leading causes of antepartum stillbirths were unspecied
causes, fetal anomalies and chromosomal abnormalities,
and fetal death due to problems related to fetal growth.
Further detailed analysis of antepartum stillbirths
revealed that 32.9% of antepartum stillbirths occurred
before 28 weeks of gestation, which is basically consistent
with the ndings of Flenady [25]. While 51.2% of ante-
partum stillbirths occurred between 28 and 37 weeks of
gestation, so this period is also worth considering.
In a Swedish study [26], it was found that causes of
stillbirths vary with gestational age, we also found that
the causes of stillbirths at dierent gestational ages were
dierent. In addition to having unspecied causes, fetal
anomalies and chromosomal abnormalities were more
common before 28 weeks of gestation, antepartum
hypoxia was the main cause between 28 and 37 weeks
of gestation, and after 37 weeks of gestation. is nd-
ing prompted us to investigate whether further subdivide
the antepartum stillborn births according to the ICD-
PM system is necessary to obtain more accurate analysis
results.
An accurate denition of the medical causes of still-
births requires a minimum: (1) a complete obstetric
record with frequent observations of maternal blood
pressure, vaginal bleeding, and fetal heart rate; (2) a gross
and histological placental examination; and (3) a fetal
autopsy [27]. In our study, more than half of stillbirths
were unexplained after review of clinical data and path-
ological examination of placenta. Autopsy is considered
an ideal method for investigating the causes of perinatal
deaths [25, 28]. Studies [29] have shown that in 22–76%
of cases, autopsies can reveal new and valuable infor-
mation. However, the autopsy acceptance rate in our
study was only 3.6%, far lower than the level of western
developed countries [30–32]. e main reason for refus-
ing autopsies in our study was traditional concept of
preserving the integrity of the body after death. ere-
fore, changing people’s traditional concept is critical to
increasing the acceptance of autopsy.
However, McPherson emphasized that determining
the exact cause of a baby’s death can be dicult even if
an autopsy was performed [33]. Some studies [27, 34,
Fig. 5 The reasons for refusing chromosomal microarray analysis
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Page 9 of 10
Feng et al. BMC Pregnancy and Childbirth (2024) 24:164
35] have suggested that CMA can help to determine the
cause of stillbirth, but this may not be certain at pres-
ent [36]. In our study, only 10.5% of parents received
CMA, and 13.6% of them had abnormalities, suggesting
that CMA may contribute to the identication of causes
of stillbirths. e main reasons for rejecting CMA were
a lack of understanding of CMA and high costs; thus,
increasing the publicity of relevant knowledge and lower-
ing the cost of the tests or incorporating them into medi-
cal insurance may help to increase acceptance of CMA.
Conclusion
e ICD-10 is helpful in classifying the causes of still-
births, but more than half of the stillbirths in our study
were unexplained; therefore, additional work is needed.
e ICD-10 score may need to be improved, such as by
classifying stillborn patients according to gestational age.
Regular obstetric examination is highly important for
reducing the incidence of antepartum stillbirths. Autopsy
and CMA could help to determine the causes of still-
births, but their acceptance rates are currently low.
Abbreviations
LMICs Low and middle-income countries
ICD-10 International Classication of Diseases, tenth revision
ICD-PM International Classication of Diseases for Perinatal Mortality
CMA Chromosomal microarray analysis
BMI Body mass index
Supplementary Information
The online version contains supplementary material available at https://doi.
org/10.1186/s12884-024-06313-5.
Supplementary Material 1
Acknowledgements
We thank ping feng for her help on information collection.
Author contributions
The manuscript has been read and approved by all authors and all authors
contributed to the manuscript. CSF and SFL conceived and designed the
study. HHJ undertook collection, cleaning, analysis and interpretation of
the data and wrote the earlier manuscript drafts. CSF revised subsequent
manuscript drafts, reviewed records, and prepared tables and gures. CSF
reviewed data analysis and interpretation. CSF and SFL provided expertise
throughout the study and contributed to the critical revision of the
manuscript. CSF supervised all aspects of the study.
Funding
There was no external funding for this study.
Data availability
All data are available from the corresponding author on reasonable request.
Declarations
Competing interests
The authors declare that they have no nancial or nonnancial conicts of
interest related to the subject matter or materials discussed in the manuscript.
Ethics approval and consent to participate
This study was reviewed by the Institutional Review Board of Changzhou
Women and Children’s Health Hospital Aliated to Nanjing Medical
University on June 1, 2017 (2017003), and was unanimously approved. Ethical
Approval Statement: The Institutional Review Board (Ethics Committee of
Changzhou Maternal and Child Health Hospital) has reviewed this study
project and unanimously approved the conduct of this study (details as
per supplementary le). Due to the retrospective nature of this analysis and
the fact that the data was part of routine clinical care, informed consent for
participants included was waived by the ethics committee on condition that
all data were anonymized.
Consent for publication
Not applicable.
Supporting information
None.
Received: 10 October 2023 / Accepted: 1 February 2024
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