Gestational diabetes mellitus (GDM) is defined as glucose intolerance with onset or first recognition during pregnancy, irrespective of the need for insulin or persistence after delivery [1]. It is one of the most common medical complications of pregnancy, with global prevalence estimates ranging from 5% to 20%, depending on the diagnostic criteria used and the population studied [2,3]. In India, the reported prevalence varies widely, from 3.8% in rural areas to over 17% in urban settings, reflecting differences in lifestyle, dietary patterns, and genetic predisposition [4,5].

Pregnancy induces physiological insulin resistance due to increased levels of placental hormones such as human placental lactogen, progesterone, cortisol, and prolactin [6]. In susceptible women, this adaptation leads to hyperglycaemia, resulting in GDM. The condition has been linked to a range of adverse maternal outcomes, including hypertensive disorders, polyhydramnios, and increased rates of operative delivery [7,8], as well as fetal complications such as macrosomia, neonatal hypoglycaemia, respiratory distress, and stillbirth [9].

The long-term implications of GDM extend beyond pregnancy, as affected women have a higher risk of developing type 2 diabetes mellitus and metabolic syndrome, while their offspring are more likely to develop obesity and glucose intolerance later in life [2,3]. These risks highlight the importance of early diagnosis, optimal glycaemic control, and regular follow-up.

Despite the availability of universal screening recommendations and standardized diagnostic criteria, variations in implementation and patient compliance continue to impact clinical outcomes. There is a pressing need for context-specific data to guide antenatal care policies and strengthen prevention strategies.

The present study was undertaken to assess maternal and fetal outcomes in women with GDM attending a tertiary care hospital, with a view to identifying preventable risk factors and improving perinatal management.

Study Design and Setting

A hospital-based observational study was conducted in the Department of Obstetrics and Gynaecology at a tertiary care teaching hospital over a period of 12 months.

Study Population

The study included all pregnant women diagnosed with gestational diabetes mellitus (GDM) who attended the antenatal outpatient department or were admitted for delivery during the study period.

Sample Size and Sampling Technique
A total of 220 pregnant women with confirmed GDM were enrolled. Consecutive sampling was applied until the desired sample size was reached. The sample size was determined based on an anticipated prevalence of adverse outcomes of 20%, a 95% confidence level, and a 5% margin of error.

Inclusion Criteria

• Singleton pregnancies diagnosed with GDM using International Association of the Diabetes and Pregnancy Study Groups (IADPSG) criteria
• Gestational age ≥ 24 weeks at diagnosis
• Willing to provide informed consent

Exclusion Criteria

• Known pregestational diabetes mellitus
• Multiple pregnancies
• Pregnancies with major fetal anomalies or maternal chronic illnesses unrelated to GDM (e.g., renal failure, cardiac disease)

Diagnosis of GDM

Diagnosis was made using a 75 g oral glucose tolerance test (OGTT) performed between 24–28 weeks of gestation. GDM was confirmed if one or more of the following plasma glucose values were met or exceeded: fasting ≥ 92 mg/dL, 1-hour ≥ 180 mg/dL, or 2-hour ≥ 153 mg/dL.

Data Collection

Baseline demographic details, obstetric history, and clinical examination findings were recorded in a structured proforma. Glycaemic control was monitored through fasting and postprandial blood glucose measurements. Management included dietary modification, medical nutrition therapy, and insulin therapy when indicated.

Outcome Measures

Maternal outcomes assessed included mode of delivery, preeclampsia, polyhydramnios, and preterm labour. Fetal outcomes included birth weight, presence of macrosomia, neonatal hypoglycaemia, respiratory distress, NICU admission, and stillbirth.

Statistical Analysis

Data were entered in Microsoft Excel and analysed using SPSS version 26.0 (IBM Corp., Armonk, NY, USA). Continuous variables were expressed as mean ± standard deviation, and categorical variables as frequencies and percentages. The Chi-square test was used for categorical comparisons, and Student’s t-test for continuous variables. A p-value <0.05 was considered statistically significant.

A total of 220 pregnant women diagnosed with GDM were included in the analysis. The mean age of participants was 28.6 ± 4.2 years, with the majority in the age group of 26–35 years (62.3%). Most women were multigravida (58.2%) and presented in the third trimester at diagnosis (54.1%).

Maternal Outcomes

Caesarean section was the most common mode of delivery (58.6%), followed by spontaneous vaginal delivery (38.6%) and assisted vaginal delivery (2.8%) (Table 1). The most frequent maternal complications were preeclampsia (18.2%), polyhydramnios (12.7%), and preterm labour (9.5%) (Table 2). Women with poor glycaemic control had a significantly higher incidence of preeclampsia compared to those with good control (p=0.021).

Table 1. Mode of delivery among GDM patients (n = 220)

Table 2. Maternal complications in GDM (n = 220)

Fetal Outcomes

Macrosomia was observed in 14.5% of neonates, while 11.8% had neonatal hypoglycaemia. NICU admission was required for 16.4% of newborns, mainly for respiratory distress and hypoglycaemia (Table 3). Stillbirth occurred in 1.8% of cases. Poor glycaemic control was significantly associated with higher rates of macrosomia and NICU admission (p<0.05).

Table 3. Fetal outcomes in GDM (n = 220)

In summary, GDM was associated with higher operative delivery rates, significant maternal morbidities such as preeclampsia and polyhydramnios, and adverse neonatal outcomes, particularly macrosomia and hypoglycaemia (Tables 1–3).

This study highlights that gestational diabetes mellitus (GDM) is associated with a considerable burden of maternal and neonatal complications. The prevalence of operative delivery was high, with 58.6% of women undergoing caesarean section. Similar rates have been reported in other Indian and international studies, reflecting clinicians’ preference for surgical delivery in GDM cases due to concerns over macrosomia, fetal distress, and labour complications [1,2].

Maternal morbidities in our study were dominated by preeclampsia (18.2%), polyhydramnios (12.7%), and preterm labour (9.5%). The association between GDM and hypertensive disorders has been well documented, likely due to shared pathophysiological mechanisms involving endothelial dysfunction and insulin resistance [3,4]. Polyhydramnios may be secondary to fetal hyperglycaemia-induced osmotic diuresis, a finding consistent with earlier reports [5,6].

Macrosomia was observed in 14.5% of neonates, a proportion comparable to studies conducted in other tertiary care centres in India [7,8]. Poor glycaemic control significantly increased the risk of macrosomia and NICU admissions in our cohort, corroborating evidence that maternal hyperglycaemia directly influences excessive fetal growth via increased transplacental glucose transfer [9,10].

Neonatal hypoglycaemia (11.8%) and NICU admissions (16.4%) were also noteworthy. Hypoglycaemia is a well-recognized complication of GDM, resulting from persistent fetal hyperinsulinism after delivery [11]. In our study, most NICU admissions were due to hypoglycaemia and respiratory distress, findings consistent with previous literature [12,13].

Although stillbirth was relatively uncommon (1.8%), its occurrence underscores the need for close antenatal monitoring, particularly in women with poor glycaemic control. Several studies have shown that intensive glycaemic management and timely delivery planning can reduce perinatal mortality in GDM pregnancies [14,15].

The strength of this study lies in its hospital-based design, which allowed for systematic evaluation of maternal and neonatal outcomes. However, being a single-centre study, its findings may not be generalizable to the broader population. Additionally, long-term outcomes for both mothers and infants were not assessed, which is an important area for future research.

Gestational diabetes mellitus is associated with increased risks of operative delivery, maternal complications such as preeclampsia and polyhydramnios, and adverse neonatal outcomes including macrosomia, hypoglycaemia, and NICU admission. Early screening, optimal glycaemic control, and coordinated multidisciplinary care are essential to improve pregnancy outcomes for both mother and child.

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