Maternal And Perinatal Outcomes In Gestational Diabetes Mellitus

Study Design: This was a hospital-based observational comparative study conducted to evaluate maternal and perinatal outcomes in pregnancies complicated by gestational diabetes mellitus (GDM) and compare them with non-GDM pregnancies.

Place of Study:The study was conducted in the Department of Obstetrics and Gynaecology at a tertiary care teaching hospital.

Period of Study:The study was carried out over a period of 18 month

 

Study Variables:

Exposure variable:

Gestational diabetes mellitus (GDM status)

Diagnostic variables (GDM):

Fasting blood sugar, 1-hour glucose value, 2-hour glucose value

Treatment variables (GDM):

Diet therapy, insulin, oral hypoglycaemic agents

Baseline variables:

Maternal age, body mass index, religion, socioeconomic status, family history of diabetes

Antenatal complications:

Urinary tract infection, gestational hypertension/preeclampsia, polyhydramnios, vaginal candidiasis

Obstetric outcomes:

Preterm delivery, mode of delivery, postpartum haemorrhage, postpartum sepsis

Perinatal outcomes:

Birth weight, APGAR score (1 and 5 min), birth weight category (AFD/LFD/SFD), neonatal complications (hypoglycaemia, hyperbilirubinemia, respiratory distress syndrome, congenital anomalies)

 

Sample Size

A total of 96 pregnant women were included in the study.

•              GDM group: 48 patients

•              Non-GDM group: 48 patients

 

Inclusion Criteria

•              Pregnant women diagnosed with gestational diabetes mellitus according to standard diagnostic criteria (for GDM group)

•              Pregnant women with normal glucose tolerance (for non-GDM group)

•              Singleton pregnancy

•              Gestational age ≥ 24 weeks

•              Willingness to participate and provide informed consent

 

Exclusion Criteria

•              Pregnant women with pre-existing diabetes mellitus (Type 1 or Type 2)

•              Multiple pregnancies

•              Pregnancies complicated by chronic medical disorders such as:

o             Chronic hypertension

o             Renal disease

o             Thyroid disorders

•              Known fetal congenital anomalies

•              Incomplete medical records

 

STATISTICAL ANALYSIS

IBM SPSS version 20.0, a statistical product services solution from IBM Corp. in Armonk, New York, was used for all data analysis. The proper statistical test was used to assess the continuous data's normality assumption. Descriptive statistics including mean, standard deviation, and range values were computed for continuous variables that were normally distributed. Student's t-independent test was used to compare the means of two groups. The interquartile range and median values were calculated for nonnormal data. The nonparametric Mann-Whitney U-test was used to compare median values. Data were displayed as frequency and percent values for categorical variables. Chi-square and Fisher's exact tests were used as necessary to compare frequency data across categories. For every statistical test, a two-sided probability of P < 0.05 was deemed statistically significant.

 

Among the 48 patients diagnosed with gestational diabetes mellitus, fasting blood sugar was the most commonly used method of diagnosis, identifying 37 patients (77.1%). The 1-hour post-glucose value contributed to the diagnosis in 18 patients (37.5%), while the 2-hour value was positive in 16 patients (33.3%).

With respect to treatment modalities, the majority of patients were successfully managed with dietary modification alone, accounting for 36 cases (75.0%). Insulin therapy was required in 8 patients (16.7%), whereas oral hypoglycaemic agents were used in 4 patients (8.3%). These findings indicate that most women with gestational diabetes mellitus could be adequately controlled with non-pharmacological measures, with only a minority requiring pharmacological intervention.

The baseline characteristics of patients with gestational diabetes mellitus (GDM) and non-GDM were comparable with respect to age and body mass index. The mean age of patients in the GDM group was 28.6 ± 4.2 years, while that of the non-GDM group was 28.4 ± 4.5 years, with no statistically significant difference (p = 0.94). Similarly, the mean BMI was 25.8 ± 4.9 kg/m² in the GDM group and 25.3 ± 5.1 kg/m² in the non-GDM group, which was not statistically significant (p = 0.71).

In terms of religious distribution, Hindus constituted the majority in both groups, accounting for 62.5% in the GDM group and 58.3% in the non-GDM group, followed by Muslims and Christians. There was no significant association between religion and the occurrence of GDM (p = 0.82).

A statistically significant difference was observed in socioeconomic status between the two groups (p = 0.02). Patients belonging to the middle socioeconomic class were more common in the GDM group (62.5%) compared to the non-GDM group (45.8%), whereas a higher proportion of patients from the lower socioeconomic class was seen in the non-GDM group (37.5% vs. 20.8%).

A positive family history of diabetes mellitus was significantly more frequent among GDM patients, observed in 12 cases (25.0%), compared to 5 cases (10.4%) in the non-GDM group, and this association was statistically significant (p = 0.04).

Antenatal complications were more frequently observed among patients with gestational diabetes mellitus compared to the non-GDM group. Urinary tract infection was reported in 8 patients (16.7%) in the GDM group and in 4 patients (8.3%) in the non-GDM group; however, this difference was not statistically significant (p = 0.23).

Gestational hypertension and preeclampsia were significantly more common in the GDM group, occurring in 10 patients (20.8%) compared to 4 patients (8.3%) in the non-GDM group, and this association was statistically significant (p = 0.04). Polyhydramnios was observed only among GDM patients in 3 cases (6.3%) and was absent in the non-GDM group, though the difference did not reach statistical significance (p = 0.08). Vaginal candidiasis was noted in 4 patients (8.3%) in the GDM group and 2 patients (4.2%) in the non-GDM group, with no statistically significant difference between the groups (p = 0.40).

Preterm delivery was more frequent among patients with gestational diabetes mellitus, occurring in 7 cases (14.6%) compared to 3 cases (6.3%) in the non-GDM group, and this difference was statistically significant (p = 0.04).

Regarding the mode of delivery, vaginal delivery was observed in 22 patients (45.8%) in the GDM group and 26 patients (54.2%) in the non-GDM group. Caesarean section was performed in 24 patients (50.0%) with GDM and in 20 patients (41.7%) without GDM, while instrumental delivery was required in 2 patients (4.2%) in both groups. The difference in the mode of delivery between the two groups was not statistically significant (p = 0.29).

Postpartum complications were comparable between the groups. Postpartum haemorrhage occurred in 2 patients (4.2%) in the GDM group and in 1 patient (2.1%) in the non-GDM group, with no statistically significant difference (p = 0.55). Postpartum sepsis was noted in one patient in each group (2.1%), showing no significant association with gestational diabetes mellitus (p = 1.00).

Neonatal outcomes differed between the two groups. The mean birth weight was significantly higher in neonates born to mothers with gestational diabetes mellitus (2860.4 ± 360.2 g) compared to those born to non-GDM mothers (2705.6 ± 340.8 g), and this difference was statistically significant (p = 0.04). The Apgar scores at 1 minute and 5 minutes were comparable between the two groups, with no statistically significant differences observed (p = 0.95 and p = 0.36, respectively).

With respect to the distribution of birth weight, the majority of neonates in both groups were appropriate for dates (AFD), accounting for 66.7% in the GDM group and 62.5% in the non-GDM group. Large-for-dates (LFD) neonates were significantly more common in the GDM group (29.2%) compared to the non-GDM group (18.8%), while small-for-dates (SFD) neonates were more frequently observed in the non-GDM group (18.8% vs. 4.2%). This difference in birth weight distribution was statistically significant (p = 0.03).

Neonatal complications were more prevalent in the GDM group. Hypoglycaemia was significantly higher among neonates of GDM mothers, occurring in 10 cases (20.8%) compared to 5 cases (10.4%) in the non-GDM group (p = 0.04). Other complications, including hyperbilirubinemia, respiratory distress syndrome, and congenital anomalies, were observed more frequently in the GDM group; however, these differences were not statistically significant (p = 0.64, p = 0.40, and p = 0.40, respectively).

Out of the total study population of 96 patients, an equal number were allocated to the two groups. The gestational diabetes mellitus (GDM) group comprised 48 patients (50.0%), while the non-GDM group also included 48 patients (50.0%), indicating an equal distribution of cases and controls.

Among the 48 patients diagnosed with gestational diabetes mellitus, the majority were managed with dietary modification alone, accounting for 36 patients (75.0%). Insulin therapy was required in 8 patients (16.7%), while oral hypoglycaemic agents were used in 4 patients (8.3%). These findings suggest that most cases of gestational diabetes mellitus could be effectively controlled with non-pharmacological measures, with only a smaller proportion requiring pharmacological treatment.

In the present study, fasting blood sugar was the most commonly positive diagnostic parameter for gestational diabetes mellitus, identifying 37 out of 48 patients (77.1%). The 1-hour and 2-hour post-glucose values contributed to diagnosis in 18 (37.5%) and 16 patients (33.3%), respectively, indicating that fasting glucose remains a reliable screening tool in routine antenatal practice. With regard to management, the majority of women with GDM were successfully treated with dietary modification alone (75.0%), while insulin therapy was required in 16.7% and oral hypoglycaemic agents in 8.3% of cases. These results imply that most patients can achieve adequate glycemic control with non-pharmacological means when diagnosed early, with only a small percentage needing pharmacological intervention. Pregnancy and neonatal outcomes are known to be negatively impacted by overt diabetes mellitus. However, controversies exist regarding adverse effects of GDM due to the use of different criteria used by different studies and various confounding factors in these studies.[4]

The baseline characteristics of women with gestational diabetes mellitus (GDM) and those without GDM were comparable with respect to age and body mass index. The mean age was 28.6 ± 4.2 years in the GDM group and 28.4 ± 4.5 years in the non-GDM group (p = 0.94), while the mean BMI was 25.8 ± 4.9 kg/m² and 25.3 ± 5.1 kg/m², respectively (p = 0.71). Religious distribution was similar in both groups, with Hindus constituting the majority (62.5% in GDM vs. 58.3% in non-GDM; p = 0.82). A statistically significant difference was observed in socioeconomic status, with a higher proportion of women from the middle socioeconomic class in the GDM group (62.5%) compared to the non-GDM group (45.8%), while lower socioeconomic status was more common in the non-GDM group (37.5% vs. 20.8%; p = 0.02). Additionally, a positive family history of diabetes mellitus was significantly more frequent among GDM patients (25.0%) than non-GDM patients (10.4%), indicating a strong familial predisposition (p = 0.04).The current study indicated that the incidence of GDM was 5.72%, which was less than the 13% reported by Nair et al.[8] from Bengaluru, Pune, and Kolkata, and comparable to 7.17% by Rajput et al.[9] from Rohtak, Haryana and higher than that of 3.8% by Zargar et al.[10] from Kashmir. However, Seshiahet al.[8] According to a study, the prevalence of GDM in Tamil Nadu is quite high, at 17.8% in urban areas, 13.8% in semiurban areas, and 9.9% in rural areas. GDM was shown to be higher in medium and upper socioeconomic classes in the current study, however Rajput et al.[9]found that low socioeconomic class had a higher occurrence. In the current investigation, GDM cases had a considerably greater family history of diabetes than controls. Nair et al. found similar outcomes.[8]

Antenatal complications were observed more frequently among women with gestational diabetes mellitus. Urinary tract infection was noted in 16.7% of GDM patients compared to 8.3% of non-GDM patients, although this difference was not statistically significant (p = 0.23). Gestational hypertension and preeclampsia occurred significantly more often in the GDM group (20.8%) than in the non-GDM group (8.3%), showing a statistically significant association (p = 0.04). Polyhydramnios was observed exclusively among GDM patients (6.3%), while no cases were reported in the non-GDM group; however, this difference did not reach statistical significance (p = 0.08). Although the difference was not statistically significant (p = 0.40), vaginal candidiasis was more common in the GDM group (8.3%) than in the non-GDM group (4.2%). Prenatal problems, including preeclampsia and gestational hypertension, were considerably more common in the current study than in the controls. The outcomes are comparable to those of Nair et al.[8]

Preterm delivery was significantly more common among women with gestational diabetes mellitus, occurring in 7 patients (14.6%) compared to 3 patients (6.3%) in the non-GDM group (p = 0.04). With respect to the mode of delivery, vaginal delivery was observed in 45.8% of GDM patients and 54.2% of non-GDM patients, while caesarean section rates were higher in the GDM group (50.0%) compared to the non-GDM group (41.7%); however, this difference was not statistically significant (p = 0.29). Instrumental delivery was required in 4.2% of patients in both groups. Postpartum complications were similar in both groups: postpartum sepsis was reported in one patient (2.1%) in each group (p = 1.00), and postpartum hemorrhage occurred in 4.2% of GDM patients and 2.1% of non-GDM patients (p = 0.55). The HAPO study also found that there was no discernible difference in the mode of birth (instrumental versus cesarean) between GDM and controls.[6] and Nair et al.[8]

Neonatal outcomes differed significantly between the two groups. The mean birth weight of neonates born to mothers with gestational diabetes mellitus was significantly higher (2860.4 ± 360.2 g) compared to those born to non-GDM mothers (2705.6 ± 340.8 g; p = 0.04). Apgar scores at 1 minute (8.1 ± 1.3 vs. 8.0 ± 0.9; p = 0.95) and at 5 minutes (8.6 ± 1.4 vs. 8.7 ± 0.8; p = 0.36) were comparable between the two groups.

With regard to birth weight distribution, large-for-dates neonates were significantly more common in the GDM group (29.2%) compared to the non-GDM group (18.8%), while small-for-dates neonates were more frequently observed in the non-GDM group (18.8% vs. 4.2%), and this difference was statistically significant (p = 0.03). Neonatal hypoglycaemia occurred significantly more often among infants of GDM mothers (20.8%) than those of non-GDM mothers (10.4%; p = 0.04). Thevarajah A t al [11]Neonatal hypoglycemia (capillary glucose levels < 1.8 mmol/l) and hyperbilirubinemia (total serum bilirubin levels beyond age-appropriate limits for phototherapy) were the primary outcomes assessed. Multivariable logistic regression was used to generate the adjusted odds ratios [95% confidence interval (CI)]. The GDM group had higher rates of congenital abnormalities, respiratory distress syndrome, and hyperbilirubinemia, although these differences were not statistically significant.Large-for-date babies, birth weight, and neonatal hypoglycemia were among the parameters that Kwik et al. found to have slightly increased in GDM patients. However, most other parameters, such as mode of delivery, neonate Apgar, and instrumental deliveries, were similar in the two groups because BSs were adequately controlled by diet control, insulin, and oral hypoglycemic medications. Kwik et al. made a similar observation.[12] similar study Gasim T et al 13[2014 Pre-eclampsia (p<0.0001), preterm delivery (p=0.0226), induction of labor (p<0.0001), cesarean section (p=0.0019), large for gestational age infants (p=0.0011), macrosomia (p=0.0186), and admission to the neonatal intensive care unit (p=0.0003) were all significantly more common among patients with GDM.

 

Conclusion

In this study, gestational diabetes mellitus (GDM) was associated with increased maternal and perinatal complications. Women with GDM had a higher incidence of gestational hypertension and preeclampsia (20.8% vs. 8.3%; p = 0.04) and experienced more preterm deliveries (14.6% vs. 6.3%; p = 0.04) compared to non-GDM women. Neonates of GDM mothers had significantly higher birth weights (2860.4 ± 360.2 g vs. 2705.6 ± 340.8 g; p = 0.04) and a greater risk of hypoglycaemia (20.8% vs. 10.4%; p = 0.04). Most GDM cases were effectively managed with diet alone. Early detection and appropriate management are crucial to reduce maternal and neonatal morbidity in GDM pregnancies.

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