Pattern and outcome of gross congenital malformations at birth amongst newborns admitted to a tertiary hospital in northern Nigeria

Niger J Paed 2014; 41 (4): 337 - 340

ORIGINAL

Onankpa BO

Pattern and outcome of gross

Adamu A

congenital malformations at birth

amongst newborns admitted to a

tertiary hospital in northern

Nigeria

DOI:http://dx.doi.org/10.4314/njp.v41i4,9

Accepted: 12th April 2014

Abstract Background : Congenital

the study period were 6,578 while,

malformation(s) do occur in new-

admission to the SCBU was1165.

Onankpa BO (

)

borns and are thought to be often

Twenty four (2.1%, prevalence) of

Adamu A

responsible for a significant pro-

the neonates admitted to SCBU

Department of Paediatrics,

portion of perinatal morbidity and

had congenital malformation(s);

Usmanu Danfodiyo University

mortality worldwide.

males were 15(62.5%) and females

Teaching Hospital,

were 9(37.5%) with male to fe-

PMB 2370, Sokoto, Sokoto State,

Objective: This prospective study

Nigeria.

was designed to determine the

male ratio of 1.7:1. 6(25%) of the

E-mail: benonankpa@yahoo.com.

pattern and outcome of congenital

babies

were

delivered

outside

malformation(s) among newborn

while, 18(75%) were delivered in

deliveries admitted to the special

our facility labour room. Most of

care baby unit (SCBU) of the

the observed malformations were

Usmanu

Danfodiyo

University

seen in the central nervous system

Teaching Hospital, Sokoto.

and the gastro intestinal tract.

Methods: All newborns with any

Conclusion: There is the need for

form of congenital malformation

early diagnosis and treatment to

(s) admitted to the SCBU were

improve the chance of survival for

recruited for the study for a 2-year

malformed babies. The prevalence

period from January, 2011 to De-

of 2.1% in our study is comparable

cember, 2012. For ease of identi-

to some previous studies however,

fication and classification, organ

a community based/multi-centre

systems were used to classify

studies may illuminate a true

malformations while, the recog-

prevalence.

nized syndromes were classified

under others.

Key words: congenital malforma-

Results: The total deliveries for

tions, newborns

Introduction

present in one of every three babies that die in the

world and their effects on a child vary depending

According to the World Health Organization (WHO)

greatly on the severity of the defect and whether or not

document of 1972, the term congenital malformations

other medical problems are present. The etiology of con-

should be confined to structural defects at birth.

1-3

Con-

genital abnormality may be genetic (30–40%) or envi-

ronmental (5–10%) . Among genetic causes, chromoso-

genital malformations are single or multiple defects of

the morphogenesis of organs identifiable at birth or at

mal abnormality makes up about 6%, single gene disor-

the intrauterine life. The global prevalence

1-3

is about 2-

ders about 25%, and multifactorial factors 20–30%. In

about 50% of cases, the cause is not known . Any insult

3%. Considering the mechanism for the forms of con-

genital anomalis,

congenital malformations may be

within the early intrauterine period may result in con-

genital abnormalities . The prevalence of congenital

classified based on the etiologic, clinical or pathogenetic

criteria. There is an intrinsically abnormal developmen-

abnormalities ranges from 1% to over 4% depending on

the place and population studied

tal process, with the early development of a tissue or

organ being arrested, delayed, or misdirected. These

anomalies can be caused by a teratogen or abnormalities

Congenital abnormality plays a major role in morbidity

in a gene, a group of genes, or a chromosome.

and mortality of children especially at the perinatal pe-

riod 2, 4

. The treatment and rehabilitation of these chil-

Congenital malformations contribute highly to prenatal

dren with congenital abnormality is very costly, hence

mortality and postnatal physical defects Aggregates of

the need to identify causative and risk factors and pre-

literature indicates that congenital malformations are

vent them early ^2,4 , where possible. Early recognition of

338

anomalies is also important for planning and care. Par-

prevalence of 2.1%. Of the babies admitted with con-

ents are likely to feel anxious and guilt on learning of

genital malformations, 15 (62.5%) were males and 9

the existence of a congenital anomaly and this require

(37.5%) were females with male to female ratio of 1.7:1.

sensitive counseling

. 2

Eighteen (75%) of the babies with congenital malforma-

tion were delivered in our facility while, the rest 6 (25%)

To the best of the authors’ knowledge, no study on con-

were delivered outside but, admitted same day. Prod-

genital malformation has been carried out in North-

ucts of multiple gestations were part of the 1165 babies

Western Nigeria; therefore, there was the need to carry

admitted to the SCBU; 18 sets of twins, 6 sets of triplets

out this study to determine the incidence of congenital

and 2 sets of quadruplets (total of 50). Two babies

malformations and the possible causal associations.

though from different set of twins, had congenital mal-

formation. Table 2 shows distribution and frequency of

congenital malformations in relation to various fetal and

maternal factors: mean birth weight (kg) of 3.26 ± 0.52

Subjects and Methods

SD with minimum of 1.82kg and maximum of 4.35kg,

mean maternal age (years) of 26 ± 6, minimum of 17

This prospective study was conducted in the Special

years and maximum of 43 years. Table 3 shows mater-

Care Baby Unit (SCBU) of Department of Pediatrics at

nal birth characteristics and occurrence of congenital

Usmanu

Danfodiyo

University teaching

Hospital,

malformation: over 60% of the mothers who had babies

Sokoto: the capital of Sokoto State, Nigeria. This terti-

with congenital malformation were seen (ANC) at third

ary hospital serves as the referral centre to its three

trimester, 79% were delivered vaginally and over 90%

neighboring States and Niger Republic.

had no family history of birth defect. Mothers less than

The study span a two year period; from January, 2011 to

20 years accounted for 62.5% babies with congenital

December, 2012. All the newborns that were delivered

anomalies while, those between 20 and 30 years had

in our facility were examined for congenital malforma-

25% babies with congenital malformation. History of

tions soon after birth. Relevant information regarding

parental consanguinity was present in nine cases of con-

maternal age, gestational age, sex, ethnicity, birth

genital malformations. Babies with congenital anomalies

weight, birth order and consanguinity was documented.

were highest in the second order to third birth order

Significant antenatal history like maternal illness, inges-

(50%). There was a history of oligohydramnios in 5/24

tion of drugs, exposure to radiation and complications of

(20.8%) cases and polyhydramnios in 2/24 (8.3%) cases.

labor was recorded. Antenatal ultrasonography (USS)

findings were noted. Relevant radiological, histo-

Table 1: Congenital malformations: Frequency, sex and birth

hematological and genetic tests were carried out. Au-

distribution

Total cases Malformed patients

topsy was not done on stillbirth and neonatal death due

to existing strong aversion for the procedure in the study

Total admissions to SCBU

165

2.1

area. There was no karyotyping due to lack of facility.

Still births

137

3.7

The author who is also the head of the neonatal unit car-

Live births

6441

0.3

ried out a thorough general, and where necessary a sys-

Male

3285

0.5

temic examination to detect any malformations at birth.

Female

3156

0.3

Where applicable, ultrasound, 3-D echocardiography,

Ambiguous

100

electrocardiogram and chest X-ray amongst others were

used routinely to detect congenital anomalies including

Table 2: Distribution of Congenital Malformations in relation

to various fetal and maternal factors

that of the internal congenital anomalies.

Characteristics No of cases per characteristics % of total (%)

For ease of identification and classification, organ sys-

Birth Weight (kg)

N=24

tems were used to classify the malformations while, the

<2.5

62.5

recognized syndromes were classified under others.

2.6 <4

29.2

Ethical clearance for the study was obtained from Ethics

8.3

committee of UDUTH, Sokoto

Gestational age at birth (weeks) N=24

The results were analyzed as simple percentages, Chi-

<37

66.7

square test were applicable was used for comparison of

37<42

20.8

>42

12.5

data and the level of statistical significance was set at

Maternal age (years)

N=24

p<0.05

<20

37.5

21-25

4.2

26-30

8.3

31-35

8.3

Results

36-40

25.0

>40

16.7

There were 6578 intramural deliveries for the 2-year

Parity

N=24

study period, 107 (1.6%) were still births. One thousand,

Primip

33.3

Para 1-3

20.8

one hundred and sixty five (1165) babies were admitted

≥ Para 4

45.8

to the Special Care Baby Unit during the study period

(Table 1); 24 had congenital malformation(s) giving the

339

Table 3: Maternal birth characteristics and congenital malfor-

the study concentrated on minor abnormalities alone

mation

which may have accounted for the lower prevalence rate

Characteristics

N (%) malformation

obtained in that study.

ANC attendance

N=18

First trimester

4(22.2)

Congenital malformation among the stillbirths ac-

Second trimester

3(16.7)

counted for 3.7%, which is in agreement with previous

reports

1,3

Third trimester

11(61.1)

Previous publications have shown that the inci-

Mode of Delivery

N= 24

dence of congenital anomalies is significantly higher in

Spontaneous Vertex

19(79.2)

preterm babies as compared to full term babies and, that

Caesarean Section

3(12.5)

there is an increased risk of congenital anomalies in ba-

Instrumental

2(8.3)

bies with low birth weight

1,11,12

Family history of birth defect

N=24

. Our study has shown a

Yes

2(8.3)

male preponderance among congenitally malformed

22(91.7)

babies and, this was in agreement with previous reports

1,11

. There was a history of consanguineous marriages

Table 4 shows the distribution of congenital malforma-

in 6 cases in our study; facts from literature showed a

tion according to the organ systems: the highest occur-

definite increase in incidence of congenital malforma-

tion amongst babies of consanguineous marriages

3,13

rence was in the central nervous system with 7 cases

. In

(29.2%) found, with an incidence of 1.1 per 1000 admis-

our study, it was observed that mothers with ages below

sions. Twelve (50%) of the cases were treated and

20 years and those above 35 years had more babies with

discharged home, 6(25%) died all within 48 hours of

congenital malformations however, some previous re-

ports

admission, 2(8.3%) were referred to the neurosurgical

showed no statistically significant association

unit of our hospital and 4(16.7%) babies were dis-

between increased maternal age and congenital malfor-

charged against medical advice.

mations. Our results are comparable with previous re-

ports

1,2,13,14

, that showed a higher incidence of malfor-

mation among the mothers of gravida four and above,

Table 4: Distribution of congenital malformation

this probably indicates that there is linear relationship

Category of malformation

n (%)

Prevalence per 1000 admissions

between incidence of congenital malformation and in-

n =24

n=6578

crease in birth order.

GIT Omphalocele

2(8.3)

0.3

Hirschprung disease

2(8.3)

0.3

Our data presented, however, might not be the true

CNS Hydrocephalus

4(16.7)

0.6

prevalence of congenital anomalies in the area of study.

Meningocele

3(12.5)

0.5

CVS Acyanotic Heart Disease 1(4.2)

0.2

This is because 75% of the babies with congenital mal-

Facial/palatial Anomalis Cleft lip and palate 1(4.2)

0.2

formation were delivered in our hospital, the rest were

GUS Posterior Uretheral valve 1(4.2)

0.2

referred from other hospitals with poor records. There-

Ambigous genitalia

1(4.2)

0.2

fore, the prevalence rate of 2.1% obtained in this study

Ocular Cataract

1(4.2)

0.2

Miscellaneous Nasal polyps

1(4.2)

0.2

does not reflect the picture in the general population as

Choanal atresia

1(4.2)

0.2

this was purely a hospital based study. In the study ar-

Limb deformity

1(4.2)

0.2

rear, due to poverty, cultural beliefs and “gate keep-

Congenital dislocation of the Hip 1(4.2)

0.2

ing” (i.e. husband’s permission is required before going

Multiple Organ deformity 4(16.7)

0.6

Total

24(100)

out of the house including seeking for emergency medi-

cal care), most pregnant women patronize traditional

birth attendants (TBA) who do not keep records of mal-

formed babies. There a strong aversion for autopsy in

the study area; the authors are aware that carrying out

Discussion

autopsies on the stillbirths may have increased the num-

ber of congenital malformations in other previous re-

ports

There is no previous recorded prevalence of congenital

abnormalities in the study area and, by extension;

the

In addition, some babies with congenital abnormalities

prevalence of congenital malformation in Nigeria has

brought to our centre do not present to the neonatology

not been properly documented due to a lack of proper

unit but are seen at other specialist units such as paediat-

record-keeping. The prevalence of congenital abnor-

ric surgery unit or neuro-surgery unit, this might repre-

malities of 2.1% observed in this study is similar to the

sent the true pattern in other centres in the country. The

findings of Obu et al and Asindi et al , that were 2.8%

fate of some of the malformed babies that are born out-

and 2.2% respectively. International prevalence figures

side the hospital included; visits to traditional healers or

of congenital malformation amongst newborns, though

left to die at home.

not from population similar to our study are comparable

with our finding; studies from India and Iran showed

Eighteen mothers out of the 24 that had malformed ba-

prevalence of 1.91% and 2.46% respectively. The fact

bies, attended ante-natal clinic (ANC); mothers that

that both studies were done in referral institutions where

were seen only at the third trimester had the highest

major congenital defects are admitted may offer some

number of the babies with congenital malformation

explanation for the observed similarities. A study from a

(61.1%). It is therefore possible that either lack of ante-

regional hospital in Oman

gave a prevalence of 1.2%;

natal care or delay in commencing ante natal-care in the

340

early period of pregnancy when organogenesis begins,

Conclusion

may have contributed to these observed higher numbers

at the third trimester.

The prevalence of congenital malformation in our study

was 2.1% with the commonest malformations seen in

In our study, central nervous system abnormalities ac-

the central nervous system. The prevalence rate obtained

counted for more of the observed congenital malforma-

in this study, however, may not reflect the true situation

tions in the babies studied with a prevalence of 1.1 per

in the general population for reasons given above, there-

1000 admissions, this is in keeping with the other previ-

fore, a community based/multi-centre studies may illu-

ous reports

15,16

. However, facts from other centres in

minate a true prevalence.

Nigeria

17,18

. showed more occurrences in the gastro in-

Congenital anomalies are a major cause of stillbirths and

testinal tract. These differences in the pattern of distribu-

infant mortality; there is the need for early diagnosis and

tion might be due to paucity in investigative procedures

treatment for better chance of survival for the mal-

such as karyotyping and aversion for autopsy in the

formed babies.

study arrear.

Conflict of interest: None

Funding: Authors

References

Patel ZM, Adhia RA. Birth defects

8 .

Asindi AA, Ibia EO, Udo JJ : Mor-

15. DeGalan-Roseen AEM, Kuijpers

surveillance study. Indian J Pedi-

tality pattern in Nigerian children

JC, Meershock APJ, Van Velzen

atr 2005;72:489-91.

in the 1980s. J Trop Med

D, Contribution of congenital

2 .

Obu HA , Chinawa J , Uleanya N ,

Hyg 1991, 94 : 152-5 .

malformations to perinatal mortal-

Adimora G, Obi I Congenital mal-

Hudgins I, Cassidy SB: Congenital

ity: a 10-years prospective regional

formations among newborns

malformations among live births at

study in The Netherlands. Eur J

admitted in the neonatal unit of a

Arvand Hospital Ahwaz, Iran.

Obstet Gynecol Reprod Biol

tertiary hospital in Enugu, South-

Pak J Med Sci 2008, 24 : 33-37.

1998;80:545-55

East Nigeria - a retrospective

10. Sawardeker KP: Prevalence of

16. Ekanem BT, Okon ED, Akpantah

study BMC Notes 2012, 5 : 177-

isolated minor congenital abnor-

OA et al,

Prevalence of congeni-

180

malities in a regional

tal malformations in Cross River

Taksande A, Vilhektar K,

hospital in Oman . Saudi Med J

and Akwa Ibom states of Nigeria

Chaturvedi P, Jain M, Congenital

2005, 26 : 1567-72

from 1980–2003. Congenital

malformation at central India; A

11. International statistical classifica-

Anomalies 2008; 48, 167–170

rural medical college base data

tion of diseases and related health

17. Fadero FF, Oyedeji OA, Onigbinde

problems (ICD-10), 10 Rev,

2010;16:159-163

MO. The pattern of congenital

Corsello G, Giuffrè M Congenital

Geneva: World health Organiza-

malformations at Ladoke Akintola

malformations, J Matern Fetal

tion, 1992

University of Technology, Osogbo,

Neonatal Med. 2012 ;1:25-9.

12.

Muktar MY. Clinical pattern and

Niger J Paediatr 2006;33:85-89

Khoshnood B, De Vigan C,

perinatal outcome of major con-

18. Adeyemo AA, Okolo CM, Omo-

Vodovar V, Goujard J, Lhomme

genital malformation seen at

tade OO, Major congenital malfor-

A, Bonnet D and Goffinet F,

Aminu Kano Teaching Hospital

mations among paediatric

Trends in Prenatal Diagnosis,

Kano, Nigeria, Sahel Med J 2006;

admissions natb University College

Pregnancy Termination, and Peri-

9:23-25

Hospital, Ibadan, Nigeria. Ann

natal Mortality of Newborns with

13. Mathur BC, Karan S, Vijaya Devi

Trop Paediatr 1999;14:75-79

Congenital Heart Disease in

KK. Congenital malformations in

France, 1983-2000: A Population-

the newborn. Indian Pediatr

Based Evaluation. Pediatrics,

1975;12:179-83.

2005; 115: 1: 95-101

14. Datta V, Chaturvedi P. Congenital

Rajangam S, Devi R: Consagunity

malformations in rural Maharash-

and chromosomal abnormality in

tra. Indian Pediatr 2000;37:998-

mental retardation and or

1001.

multiple congenital anomalies. J

Anat Soc India 2007, 56 : 30-33.

Malla BK: One year overview

study of congenital anatomical

malformation at birth in Maternity

Hospital, Thapathali, Kathmandu.

Kathmandu Uni Med J 2007,

5:557-60.