Affiliations
doi: 10.29271/jcpsppg.2025.01.79ABSTRACT
Objective: To determine the frequency, underlying causes, and maternal and perinatal risk factors associated with Neonatal Intensive Care Unit (NICU) admissions among term neonates at a tertiary care hospital in Karachi, and to identify preventable factors to enhance antenatal, intrapartum, and immediate postpartum care.
Study Design: A prospective cohort study.
Place and Duration of the Study: Department of Obstetrics and Gynaecology, Memon Medical Institute Hospital, Karachi, Pakistan, from January to June 2024.
Methodology: Using non-probability consecutive sampling, the study included term neonates (370⁄7–416⁄7 weeks) admitted to the NICU within 48 hours of birth. Exclusion criteria were preterm birth (<37 weeks), post-term birth (>42 weeks), multiple gestations, congenital anomalies, and major maternal illnesses such as cardiac disease, lupus, or rheumatoid arthritis. Frequencies and risk factors were analysed descriptively.
Results: Of 1,200 deliveries, 150 (12.5%) neonates were admitted to the NICU, and 100 term infants (8.3% of all births, 66% of NICU admissions) met the inclusion criteria. Early-term neonates (37–38 weeks) comprised 78% of admissions, with 57% at 37 weeks and 21% at 38 weeks. Maternal comorbidities included gestational diabetes mellitus (GDM) (35%), chronic hypertension (21%), pregnancy- induced hypertension (PIH) (16%), preterm prelabour rupture of membranes (PPROM) (15%), and hypothyroidism (9%). Delivery mode was caesarean section in 52% of cases (EL‑LSCS 34.6%; breech in labour 25%; foetal distress 23.1%; abnormal foetal Doppler 17.3%) and vaginal delivery in 48% (induced 60.4%; spontaneous 39.6%). The primary NICU diagnoses were respiratory distress (54%), small for gestational age (SGA) (23%), intrauterine growth restriction (IUGR) (9%), meconium aspiration (8%), and neonatal jaundice (6%). The majority of neonates (53%) were admitted to NICU immediately after birth, 12% within the first 2 hours, and 23% within 24 hours.
Conclusion: Term NICU admissions were closely linked with modifiable perinatal factors, particularly early‑term delivery, maternal complications (GDM and hypertension), and delivery practices. Recognition of these predictors offers opportunities for targeted antenatal surveillance, optimal timing of delivery, and enhanced delivery-room preparedness, potentially reducing preventable neonatal morbidity and NICU utilisation.
Key Words: Neonatal Intensive Care Unit, Infants, Newborns, Respiratory distress, Perinatal Complications, Antenatal care.
INTRODUCTION
Neonatal intensive care units (NICUs) are principally designed to support preterm infants; however, in practice, a large proportion of NICU admissions involve more mature term newborns.1 In fact, infants born at or after 34 weeks’ gestation account for over 80% of NICU admissions.1 Admission of a term infant often indicates a perinatal complication period, such as respiratory distress, infection, birth asphyxia, or metabolic problems, and may reflect shortcomings in antenatal or intrapartum care.1,2
These NICU admissions impose emotional and financial burdens on families and place additional strain on limited healthcare resources, especially in low-resource settings. Many of these admissions are preventable through improved maternal-foetal monitoring and timely obstetric interventions.1,2 Therefore, understanding the causes and risk factors for NICU admissions among term infants is essential for improving neonatal outcomes and reducing unnecessary utilisation of limited intensive care resources.
Common indications for NICU admission in term infants include respiratory and infectious conditions. For example, a large study reported that the leading diagnoses were neonatal sepsis (27.3%), respiratory distress syndrome (RDS) (24.9%), and birth asphyxia (13.1%).3 Other frequent causes include transient tachypnoea of the newborn (especially after caesarean delivery), hypoglycaemia, meconium aspiration syndrome (MAS), and severe hyperbilirubinaemia. However, the frequency of these complications varies with the context and quality of care. For instance, infants born by elective caesarean delivery or at early-term (37-38 weeks) are known to have higher rates of respiratory morbidities and NICU admissions.2,4 In a population-based Australian study, approximately 9% of term infants born to first-time mothers and 6% of those born to multiparous mothers were admitted to the NICU, with the odds of admission markedly elevated for births by caesarean section at 37–39 weeks.2 Likewise, an Israeli cohort of over 190,000 term births identified gestational diabetes mellitus (GDM), hypertension, nulliparity, and birth at 37 weeks as significant predictors of NICU admission.4 Collectively, these studies underscore that late-preterm and early-term gestation, operative delivery, and maternal comorbidities are major drivers of morbidity among term infants.
Key risk factors for NICU admission in term infants have been consistently identified. They include maternal factors such as GDM and hypertensive disorders, as well as obstetric factors such as first pregnancies (nulliparity) and caesarean delivery (especially elective, pre-labour caesareans).2,4 Some factors, such as early-term birth, also increase risk; infants born at 37–38 weeks have significantly higher NICU admission rates compared to those born at 39-40 weeks.2,4 Clinically, adverse birth conditions, such as low Apgar scores, foetal bradycardia, or need for resuscitation, are closely linked to NICU transfer. In summary, international data highlight a web of interconnected maternal, foetal, and delivery factors that increase the likelihood of NICU admission.
Nevertheless, NICU admission rates and underlying causes vary widely by setting. Developed countries often report overall term NICU admission rates in single digits (approximately 2-9% of term births),2,4 whereas low-resource settings often experience higher rates and intensified disease burdens. In the South Asian region including Pakistan, neonatal mortality remains alarmingly high (28–42 deaths per 1,000 live births),5,6 with many deaths stemming from perinatal complications. A large cohort study from the region found that maternal morbidities affected one-third of pregnancies and were strongly associated with neonatal mortality.6 Local audits indicate that term NICU admissions are frequently due to birth asphyxia, respiratory compromise, and infection¾conditions tied to gaps in care.3,5 For example, analysis of NICU admissions in Jordan, a low-middle income setting, identified similar drivers of morbidity including sepsis, RDS, and asphyxia.3 In Pakistan’s Sindh province, direct observations have documented poor quality of intrapartum care, such as inadequate monitoring of vital signs and delayed recognition of foetal distress, which likely contributes to avoidable neonatal complications.7 Moreover, gaps in antenatal coverage, nutritional deficiencies, and limited access to emergency obstetric services are common in the region,5,7 highlighting the preventable nature of many term NICU admissions. Crucially, although global and regional studies have outlined key risk factors, there is a notable lack of local research focusing specifically on term infants admitted to NICUs in Pakistan. Most published literature from Pakistan focuses on overall neonatal mortality or outcomes in preterm infants, with limited reports describing case profiles of term-NICU.5,7 To the best of the authors’ knowledge, no previous study has syste- matically examined the frequency and predictors of term infant NICU admissions at Memon Medical Institute Hospital (MMIH), Karachi. In a low-resource hospital setting, such data are essential; identifying modifiable risk factors (e.g., suboptimal glucose control in diabetic mothers or late detection of foetal growth restriction) can guide targeted interventions. Improved antenatal screening and intrapartum monitoring (appropriate use of cardiotocography [CTG]), with timely obstetric decision- making, may reduce preventable NICU admissions and improve neonatal outcomes.1,4
Given the lack of local data, the present study aimed to determine the frequency of NICU admissions among term infants at MMIH and to identify predictors of these admissions. By analysing maternal health parameters, labour processes, and immediate neonatal status, this cohort aimed to highlight common risk factors leading to NICU utilisation in this population.
METHODOLOGY
A prospective, cohort study was conducted in the Department of Obstetrics and Gynaecology, Labour Ward, MMIH, Karachi, Pakistan, between January and June 2024. MMIH is a tertiary- care facility with a 332-bed capacity and a Level III NICU. Ethical approval was obtained from the Institutional Review Committee of the hospital. A non-probability consecutive sampling method was employed, enrolling all eligible mother–infant dyads. The sample size was determined using Cochran’s formula, with a 95% confidence level (z = 1.96), a prevalence of 49% (based on Verma et al.’s study),8 and a 10% margin of error, yielding a required sample of 96 dyads. The inclusion criteria were singleton neonates born at 370⁄7–416⁄7 weeks’ gestation and admitted to the NICU within 48 hours of birth.
Preterm (<37 weeks) or post-term (>42 weeks) neonates, multiple gestations, those with significant congenital anomalies, and those born to mothers with cardiac or autoimmune disorders (e.g., SLE, rheumatoid arthritis) were excluded.
Gestational age was determined using the last menstrual period (LMP), confirmed or adjusted with a first-trimester ultrasound, in accordance with ACOG recommendations. Contemporary studies demonstrate that early ultrasound dating is more accurate than LMP alone.9,10
After obtaining informed consent prenatally, a structured proforma was used to collect data on maternal demographics (age, BMI, and parity); antenatal complications (GDM, chronic hypertension, pregnancy-induced hypertension [PIH], preterm prelabour rupture of membranes [PPROM], hypothyroidism, and placenta previa/abruption); intrapartum observations (CTG monitoring, foetal Doppler findings, delivery mode, and indications such as elective lower segment caesarean section [EL-LSCS], foetal distress, or breech); and neonatal outcomes (birth weight, APGAR scores, and established NICU diagnoses, including RDS, small-for-gestational-age [SGA], meconium aspiration (MAS), sepsis, hypoglycaemia, and jaundice).
Respiratory distress was defined as laboured breathing requiring respiratory support (oxygen, CPAP, or mechanical ventilation). SGA was defined as birth weight below the 10th percentile. Admission diagnoses also included MAS, neonatal sepsis, birth asphyxia, hypoglycaemia, and jaundice.11
Data were directly entered into SPSS version 20.0 using structured coding. Analyses were strictly descriptive, presenting frequencies and percentages of maternal, intrapartum, and neonatal characteristics, following the approach used in similar observational NICU studies.12
RESULTS
During the study period, a total of 1,200 neonates were delivered, of whom 150 required NICU admission for various medical reasons. This resulted in an overall NICU admission rate of 12.5%. Of these, 100 neonates (66% of NICU admissions and 8.3% of total deliveries) met the inclusion criteria; data were collected from their records.
Analysing gestational age at the time of NICU admission revealed that 57% of neonates were admitted at 37 weeks, 21% at 38 weeks, 16% at 39 weeks, and 6% at 40 weeks. These figures suggest a higher frequency of NICU admissions for early-term neonates, as 78% of admissions were those born between 37 and 38 weeks (Table I).
Table I: Baseline characteristics of study participants.
| Variables |
Frequencies (n%) |
| Parity | - |
|
Primigravida |
49 (49%) |
|
Multigravida |
51 (51%) |
|
BMI |
- |
|
<18 |
6 (6%) |
|
18-25 |
48 (48%) |
|
>25 |
46 (46%) |
|
Gestational age at admission |
- |
|
37 weeks |
57 (57%) |
|
38 weeks |
21 (21%) |
|
39 weeks |
16 (16%) |
|
40 weeks |
6 (6%) |
|
Stages of labour |
- |
|
1st stage |
64 (64%) |
|
2nd stage |
7 (7%) |
|
Not in labour |
29 (29%) |
|
CTG |
- |
|
Pathological |
3 (3%) |
|
Reactive |
73 (73%) |
|
Suspicious |
24 (24%) |
|
Caesarean delivery |
- |
|
Yes |
52 (52%) |
|
No |
48 (48%) |
|
Postnatal bay disposition |
- |
|
NICU |
72 (72%) |
|
With mother |
28 (28%) |
|
Timings of NICU admission |
- |
|
Immediately |
53 (53%) |
|
Within 2 hours |
12 (12%) |
|
Within 12 hours |
5 (5%) |
|
Within 24 hours |
23 (23%) |
|
Within 48 hours |
7 (7%) |
Among antenatal complications, GDM was the most prevalent, affecting 35% of the mothers, followed by chronic hypertension (21%). Other notable antenatal issues included PPROM (15%), PIH (16%), and hypothyroidism (9%), as shown in Table II. These maternal conditions were identified as significant risk factors for NICU admissions, with GDM being the most strongly associated. Further analysis revealed that 53% neonates were admitted to the NICU immediately after birth, 23% within 24 hours, and 12% within the first 2 hours of delivery.
Regarding delivery mode, 52% of neonates were delivered through caesarean section, while 48% were born through vaginal delivery (Table I). This indicates a near-equal distribution between the two modes of delivery.
Table II: Antenatal complications and their respective frequencies.
|
Antenatal complications |
Frequencies (n, %) |
|
Gestational diabetes mellitus (GDM) |
35 (35%) |
|
Chronic hypertension |
21 (21%) |
|
Pregnancy-induced hypertension |
16 (16%) |
|
Preterm premature rupture of membranes (PPROM) |
15 (15%) |
|
Hypothyroidism |
9 (9%) |
Table III: Causes of caesarean delivery.
|
Causes |
Frequencies |
Percentages |
|
Foetal distress |
12 |
23.08 |
|
Abnormal Doppler |
9 |
17.31 |
|
Breech in labour |
13 |
25 |
|
El-LSCS |
18 |
34.62 |
|
Total |
52 |
100 |
Table IV: Causes of admission for vaginal birth.
|
Causes |
Frequencies |
Percentages |
|
Spontaneous |
19 |
39.58 |
|
Induced |
29 |
60.41 |
|
Total |
48 |
100 |
Figure 1: The causes for admission along with their frequencies.
Out of the 52 caesarean deliveries, the leading indication was EL-LSCS, which accounted for 34.62% of caesarean births. Other notable clinical indications for caesarean delivery included breech presentation in labour (25%), foetal distress (23.08%), and abnormal foetal Doppler findings (17.31%), as shown in Table III. Among 48 vaginal deliveries, the most frequent reasons for admission were induction of labour (60.41%) and spontaneous labour (39.58%), as shown in Table IV.
The most common causes for NICU admission were respiratory distress (54%), followed by SGA (23%), IUGR (9%), MAS (8%), and neonatal jaundice (6%) as shown in Figure 1. Respiratory distress, in particular, was the most prevalent reason for admission, reflecting the potential neonatal complications associated with caesarean deliveries and early-term births.
DISCUSSION
This cohort study examined 100 (8.3%) term neonates admitted to the NICU out of 1,200 live births. This admission rate aligns with international estimates, indicating that 5–10% of term infants require intensive care depending on the context and healthcare infrastructure.4 It highlights a rising trend of NICU utilisation even among term-born infants worldwide.
Notably, 78% of NICU admissions were early-term (37–38 weeks), corroborating global data showing higher NICU rates in this group. US data reveal that NICU admissions for early-term infants rose from 6.2% to 7.1% between 2016 and 2023.13 Furthermore, a large US cohort showed that early-term infants had up to a 2.1-fold higher risk of respiratory complications and NICU admission morbidities compared to full-term infants.14 A Polish study reported similar findings, highlighting the continued vulnerability of this gestational window.15 The present data echo these international observations, highlighting the need for obstetric protocols that prioritise delivery at ≥39 weeks when medically feasible.
Eleven randomised controlled and observational analyses have demonstrated that EL-LSCS at 37–38 weeks leads to significantly higher neonatal respiratory complications. One study found early-term EL-LSCS increased NICU admissions rates to 12.2%, compared to 7.5% in full-term cohorts.16 In the present study, respiratory distress remained the leading cause of NICU admission. Data from a meta-analysis confirm that RDS affects approximately 7% of term infants and is disproportionately over represented in early-term and caesarean-delivered neonates.17 The elevated rate of respiratory distress is likely attributable to incomplete alveolar fluid clearance and surfactant immaturity, particularly in infants born by elective caesarean section prior to the onset of labour.
Among antenatal risk factors, GDM was identified in 35% of the study population and showed a significant association with neonatal respiratory distress. A comprehensive meta-analysis of 44 studies demonstrated that GDM nearly doubles the odds of developing RDS (OR 1.9; 95% CI 1.5–2.3).18 These findings mirror the present cohort, emphasising the critical need for robust prenatal glucose control to improve neonatal respiratory outcomes. SGA neonates accounted for 23% of NICU admissions in this study. A multicentre study combining foetal weight percentiles and Doppler flow analysis reported an area under curve (AUC) of 0.71 for predicting neonatal admission risk in SGA pregnancies.19 As SGA infants are susceptible to hypoglycaemia and respiratory compromise, early detection through enhanced ultrasound surveillance is indicated. Chronic hypertension (21%), PIH (16%), and PPROM (15%) were also prevalent among mothers of admitted infants. Studies confirmed that abnormal umbilical artery Doppler findings in hypertensive pregnancies increase the risk of NICU admission by up to 1.8- fold.20 Similarly, PPROM remains a recognised contributor to neonatal morbidity even at term, reinforcing the need for vigilant foetal monitoring in affected pregnancies. Morbidity of PPROM was associated with neonatal sepsis.
Most NICU admissions occurred within two hours of birth, consistent with findings that metabolic and respiratory complications typically manifest shortly after delivery. This underlines the importance of ensuring NICU preparedness at the time of birth, especially for early-term and those delivered by high-risk caesarean section.
Based on the study findings, several recommendations were proposed. Elective early-term deliveries (<39 weeks) should be avoided unless medically required, in line with guidelines from the American College of Obstetricians and Gynecologists (ACOG) and the Society for Maternal-Foetal Medicine (SMFM).21 In selected early-term cesarean cases, administration of antenatal corticosteroids is advisable, as RCTs have demonstrated a significant reduction in respiratory risk.22 Optimal management of GDM through early oral glucose tolerance testing and strict glycaemic control is essential to reduce neonatal respiratory complications. Enhanced surveillance for SGA pregnancies, including serial ultrasound and Doppler assessments, is recommended to enable the timely identification of at-risk foetuses. Delivery-room preparedness should be ensured with respiratory support resources readily available near high-risk delivery rooms, particularly for early-term caesarean births. These interventions are supported by robust clinical data and have shown efficacy in diverse healthcare systems.
The 8.3% NICU admission rate observed in this study parallels the findings from China (6.8%) and Israel (~2.75%).4,19 A recent predictive algorithm integrating maternal, obstetric, and neonatal factors achieved an AUC of 0.75, highlighting the feasibility of risk-stratification tools in this population.19
The limitations of this study were that it was a single-centre study, which limited its applicability across different settings. The study duration was six months. The absence of long-term outcome data was another limitation, though previous research suggested that term NICU admissions were associated with elevated early-childhood mortality.4
CONCLUSION
The term NICU admissions in this study were primarily driven by early-term delivery, elective caesarean section without labour pain, respiratory distress, and antenatal risks such as GDM and hypertension. By aligning clinical practice to delay delivery to ≥39 weeks when possible, enhancing maternal risk management, and ensuring delivery-room preparedness for immediate neonatal support may substantially reduce preventable neonatal morbidity and NICU admissions, particularly in resource-limited settings.
ETHICAL APPROVAL:
Ethical approval was obtained from the Institutional Review Board of the Memon Medical Institute Hospital, Karachi. The investigation adhered to the Declaration of Helsinki.
PATIENTS’ CONSENT:
Informed consent was taken from the participants before delivery.
COMPETING INTEREST:
The authors declared no conflict of interest.
AUTHORS’ CONTRIBUTION:
FM: Conceptualisation, literature review, and drafting of the manuscript.
FM, SKL: Supervision and editing.
Both authors approved the final version of the manuscript to be published.
REFERENCES