K P Paulose
SUT Hospital, Thiruvananthapuram

Corresponding Author: Dr. K P Paulose, MD, FACP, FRCP (Lond), Chief Physician, SUT Hospital, Thiruvananthapuram. Phone: 9526769777.  Email: simlupaul@gmail.com

ABSTRACT

Introduction: The most prevalent chronic medical condition in the pregnant population is diabetes. The prevalence of gestational diabetes  is increasing globally and may be as high as 14%, particularly in women from ethnic minority group.

Objective: To find out the prevalence and of gestational diabetes and to see the perinatal outcome.

Methodology: A total  of 700  patients who attended the antenatal clinic of the S U T Hospital  were studied. Patients with  history  of  Pre-gestational diabetes  were excluded. Two tests were done during  the study: the glucose challenge test, followed by the 0’Sullivan Test.

Result: The study  group comprised of patients who belonged to the higher  socio-economic strata. There  were a total of 78 patients with gestation al diabetes (GDM). Thus the prevalence of GDM was found to be 11.2% which was quite high compared  to different studies.

Materials and Methods

Table 1. Prevalence of GDM- Total number of subjects studied 700

Table 1. Prevalence of GDM- Total number of subjects studied 700

A total  of 700  patients who attended the antenatal clinic of the S U T Hospital  were studied. Patients with  history  of  Pre-gestational diabetes  were excluded. Two tests were done during  the study: the glucose challenge test, followed by the 0’Sullivan Test.

Non diabetic patients were taken  as controls.  All these  patients were followed upto delivery and the perinatal outcome analyzed. Complications such as PIH.  IUGR, hydramnios, macrosomia and intra uterine death, during antenatal period; prematurity, shoulder dystocia, hypoglycemia, hypocalcaemia, jaundice and  neonatal  death  during  the  post  natal period  were the  parameters analysed. Statistical analysis for  determining the significance  was also done  using the chi-square test.

Result

Table 2. Antenatal complications

Table 2. Antenatal complications

Our study  group comprised of patients who belonged to the higher  socio-economic strata. There  were a total of 78 patients with gestation al diabetes (GDM). Thus the prevalence of GDM was found to be 11.2% which was quite high compared  to different studies.

Discussion

The most prevalent chronic medical condition in the pregnant population is diabetes. Diabetes  in pregnancy  is classified  as Pregestational diabetes (established Type  l diabetes & Type 2 DM before pregnancy or established impaired glucose tolerance (IGT)  and impaired  fasting  glucose (IFG)  before pregnancy) and  Gestational diabetes which is vdefined as ‘carbohydrate intolerance of  varying degrees  of severity  with onset or first recognition during  pregnancy’. There is general consensus that the prevalence of gestational diabetes  is increasing globally and may be as high as 14%, particularly in women from ethnic minority group.

Table 3. Foetal complications

Table 3. Foetal complications

Risk assessment for GDM should be undertaken at the first  prenatal  visit. Women should be tested as soon a feasible, and if they are found not to have GDM at that initial screening, they should be retested between 24 and 28 weeks of gestation. Women of average risk should  have testing undertaken at 24-28 weeks of gestation.

Two or more of the venous plasma concentrations must  be  exceeded for  a  positive  diagnosis of Gestational Diabetes. 100 or 75g of glucose can be given.2

The normal values have been further reduced by WHO. Pregnant  women who shows a 2hr. Post glucose value of 140 mg% or more (after 75gm  of glucose) are classified as having gestational diabetes and in the range of 120-140 mg as having impaired gestational diabetes. The target values to be maintained is fasting blood sugar below 95 mg%, and Post Prandial Blood Sugar 120mg%.3

Table 4. Diagnosis of GDM with a 100g or 75g glucose load (OGTT) (Venousplasma glucose level)

Table 4. Diagnosis of GDM with a 100g or 75g glucose load (OGTT) (Venousplasma glucose level)

The  role of oxidative stress and the effect of tumour necrosis factor-alfa (TNF-”) and  apoptosis  play a role  in  the  occurrence of  embryopathy. The prevalence of major congenital malformations is three to five times greater in infants of diabetic mothers than in the offspring of non diabetic women. Diabetes is associated with a variety of malformations, mainly related to  the  bea1t,  central  nervous system, musculoskeletal  system and renal system. The pathognomonic  malformation  associated  with  both type 1 and  type 2 diabetes is caudal  regression syndrome or sacral agenesis, which is at least 200- fold more frequent. Although the weight of infants of diabetic mothers tend to be skewed towards the upper range, intra-uterine growth restriction (IUGR), defined as  a  weight less  than  10th centile for gestational age, can also occur. IUGR can occur in those  mothers with  complicated  diabetes  with hypertension  and renal  disease. The  intelligence quotient is found to be lower in low birth weight children of diabetic mothers and low birth weight is a risk  factor  for  future adult  diseases including hypertension, cardiovascular disease and diabetes.6  Macrosomia  is defined  as birth weight  more  than 4Kg. This is due to hyperinsulinemia. A birth weight of >4kg is found in 5-10% of all infants, but may be as great as 33% in diabetic women Macrosomia contributes to a high  Caesarean section rate, prolonged labour and fetal asphyxia and in later  life contributes to increased risk of obesity and diabetes. Stillbirth is more common in diabetics, frequent in macrosomic fetuses, and occurs more commonly around 38 weeks. Fetal hyperinsulinaemia results in fetal   hypkalaemia  which can lead to cardiac arrhythmias and sudden death. Neonatal morbidities include shoulder dystocia, hypoglycaemia, hypocalcaemia, hypomagnesemia, hyperbilirubinaemia  and respiratory distress syndrome (RDS). Strict maternal glycaemic control will  significantly reduce short term  neonatal morbidities. Foetal lung maturity can be assessed by measuring phosphalidyl glycerol or lecithin in the amniotic fluid.7 Administration of betamethasone in women before delivery will reduce the risk of RDS. The  most  serious  acute  metabolic complication  is diabetic  keto acidosis, most frequently in women with type1 diabetes.  Fetal demise is usually related to the seve1ity of the metabolic decompensation which can result  in fetal acidaemia and hypoxaemia. Diabetic vascular  complications  include  retinopathy, nephropathy and hypertension.  There is  a 50% chance of  further  progression   in  those  with proliferative  or  severe  proliferative  retinopathy.  Hypertension and pre-eclampsia are two additional important risk factors for progression of retinopathy.  Pan  retinal photocoagulation  is performed   in  the presence of  proliferative or severe preproliferative disease. Diabetic nephropathy is present in 5- 10% of diabetic pregnancies related to increased  renal filtration rate seen in pregnancy. Hypertension  is also a key  factor in the progression. Strict control  of hypertension is vital to optimize pregnancy outcome in  these  women  with a target  blood  pressure  of < 130/80mm Hg.

Pregnancy-related complications include Hypertension and pre-eclampsia. The risk factors for developing pre-eclampsia  in  women  with pregestational diabetes include duration of diabetes, pre-existing hypertension, microalbumimuria and poor glycaemic control. The incidence of Polyhydramnios is reported to be between 16% and 29% and may be associated with  preterm  labour, premature rupture of membranes (PROM), sepsis, cord  prolapse and an increased risk of stillbirth.8  Normalization  of glucose  and  preconception  care  for  women  with established diabetes  reduces the incidence of  fetal ma l formations and spontaneous abortions.9

Conclusion

There  was a significant increase in the incidence of antenatal  complications   (IUGR, Pill and Hydramnios) and foetal complications (shoulder dystocia, hypoglycaemia and  hypocalcaemia) in gestational  diabetes as  compared to  normal pregnancies.

End Note

Author Information

Dr. K P Paulose, MD, FACP, FRCP (Lond),
Chief Physician, SUT Hospital,
Thiruvananthapuram

Conflict of Interest: None declared

References

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