(PROF.) DR. SRIMANTA KUMAR PAL (SENIOR GYNECOLOGIST): Screening the pregnant women for carbohydrate intolerance

When to screen in Indian context?? At 16, 24 & 32 weeks: The prevalence of GDM in our country was 16.55%GDM is a compensated metabolic abnormality & DIPSI guidelines & also ADA guidelines aim at foetal long term benefit can prevent Obesity, IGT and Diabetes in the offspring & possibly little attention is paid for maternal temporary short term compl. A) first at16th week of::B) Second screen : 24th – 28th week and finally C) around 32nd – 34thweek. Using a different glucose challenge in pregnant versus non-pregnant patients leads to confusion in the laboratory and may result in errors in applying the proper diagnostic criteria .The expected weight gain during pregnancy is 300 to 400 gm/week and total weight gain 10 to 12 kg by term. ADA) recommends two step procedures for screening and diagnosis of diabetes and that too in selective (high risk) population. Combination of regular and intermediate acting insulin before dinner may be necessary if fasting blood sugar is high. This combination of short and intermediate acting insulin in the morning and as well as in the evening is known as mixed and split dose of insulin regimen

Q. 1, Screen all women :-The Diabetes In Pregnancy Study group India (DIPSI)”has issued practice guidelines for GDM in the Indian environment. Due to high prevalence, screening is essential for all Indian pregnant women.

Q. 2: What is the recommendation of Study Group formed in 2002:-?? Ans: Between 24 and 28 weeks . -DIPSI recommends 2 hr PPBS after 75 Glucose -(to be taken in empty stomach) that as a pregnant woman walks into the antenatal clinic in the fasting state, she has to be given a 75g oral glucose load and at 2 hrs a venous blood sample is collected for estimating plasma glucose. This one step procedure of challenging women with 75 gm glucose and diagnosing GDM is simple, economical and feasible.

Q.3;When to screen?? Between 24 and 28 weeks. Screening is recommended between 24 and 28 weeks of gestation and the diagnostic criteria of ADA (American Diabetic Association) are applicable. But, DIPSI members mentioned that a team approach is ideal for managing women with GDM.

Summary of the DIPSI:-What we the obstetricians must know:- Take home message from the “The Diabetes In Pregnancy Study Group India (DIPSI)” Total 5 recommendations:-of - A) Implementation of DIPSI is like intelligent investment for future long term health benefit of foetus and not mother, If followed in preg can prevent Obesity, IGT and Diabetes in the offspring can fairly be prevented by a short term intensive care in pregnancy gives a long term pay off in the primary prevention of as the preventive medicine starts before birth. (DIPSI guidelines therefore aim at foetal long term benefit)

B) DIPSI recommends 2hr PPBS after 75 Glucose -(to be taken in empty stomach) that as a pregnant woman walks into the antenatal clinic in the fasting state, she has to be given a 75g oral glucose load and at 2 hrs a venous blood sample C) ”Intensive monitoring by , diet and insulin are the corner stone of GDM management D) They , at that time 2002 expressed doubts and concerns on the efficacy of oral agents or analogues. At that time during the study period ( 2002) use of ODA(oral Aantidiabetics ) use in GDM was controversial though their use now slowly being established ..

Until there is evidence to absolutely prove that ignoring maternal hyperglycemia when the fetal growth patterns appear normal on the ultrasonogram, it is prudent to achieve and maintain normoglycemia in every pregnancy complicated by gestational diabetes. The maternal health and fetal outcome depends upon the care by the committed team of diabetologists, obstetricians and neonatologists.

SCREENING

A) first at16th week of::B) Second screen : 24th – 28th week and finally C) around 32nd – 34thweek.

Methodà1::

DIPSI Recommended Method
As a pregnant woman walks into the antenatal clinician the fasting state, she has to be given a 75 g oral glucose load and at 2 hrs a venous blood sample is collected for estimating plasma glucose. This one step procedure of challenging women with 75 gm glucose and diagnosing GDM is simple, economical and feasible

Methodà 2:: ADA ::DIAGNOSTIC CRITERIA

This ADA timings and design of that study including glucose load was meant primarily to diagnose and pick up women who are prone to develop DM in future and do not refer to possibility of wellbeing of foetus .American Diabetes Association (Carpenter and Couston) recommends 3 hour 100 gm OGTT and Gestational Diabetes Mellitus is diagnosed if any 2 values meet or exceed FPG > 95 mg/dl, 1 hr PG > 180mg/dl, 2 hr PG > 155 mg/dl and 3 hr PG > 140 mg/dl. This criteria was originally validated against the future risk of these women developing diabetes and not on the fetal outcome. ADA:- ADA:- What’s wrong with ADA method?? American Diabetes Association (ADA) recommends two step procedures for screening and diagnosis of diabetes and that too in selective (high risk) population. Compared with selective screening, universal screening for GDM detects more cases and improves maternal and neonatal prognosis..

Carpenter himself now recommends a 2 hour OGTT with 75 gm glucose. The reason for this is that “when a glucose tolerance test is administered to non-pregnant individuals, it is standard to use the 75-g, 2-hour OGTT. Using a different glucose challenge in pregnant versus non-pregnant patients leads to confusion in the laboratory and may result in errors in applying the proper diagnostic criteria. Further, the 75-g, 2-hour OGTT is in use during pregnancy in many countries around the world, typically using the same thresholds as in non-pregnant individuals”. Depending on the risk of the women developing diabetes and not on the fetal outcome. American Diabetes Association (Carpenter and Couston) recommends 3 hour 100 gm OGTT and Gestational Diabetes Mellitus is diagnosed if any 2 values meet or exceed FPG > 95 mg/dl, 1 hr PG > 180 mg/ dl, 2 hr PG > 155 mg/dl and 3 hr PG > 140 mg/dl. This criterion was originally validated against the future
risk of these women developing diabetes and not on the fetal outcome. Carpenter himself now recommends a 2 hour OGTT with 75 gm glucose. The reason for this is that “when a glucose tolerance test is administered to non-pregnant individuals, it is standard to use the 75-g, 2-hour OGTT. Using a different glucose challenge in pregnant versus non-pregnant patients leads to
confusion in the laboratory and may result in errors in applying the proper diagnostic criteria. Further, the 75-g, 2-hour OGTT is in use during pregnancy in many countries around the world, typically using the same thresholds as in non-pregnant individuals”.

Methodà 3 :- A) first at16th week of::B) Second screen : 24th – 28th week and finally C) around 32nd – 34thweek. WHO:-:-the World Health Organisation (WHO)To standardize the diagnosis of GDM, the World Health Organisation (WHO) proposed using a 2 hour 75 gm OGTT with a threshold plasma glucose concentration of greater than 140 mg/dl at 2 hour, similar to that of IGT, outside pregnancy. Still all these recommendations (ADA and WHO) have not projected the influence of the glycemic level on fetal outcome.

To standardize the diagnosis of GDM, the World Health Organisation (WHO) proposed using a 2 hour 75 gm OGTT with a threshold plasma glucose concentration of greater than 140 mg/dl at 2 hour, similar to that of IGT, outside pregnancy.

The fallacy is still on as all these recommendations (ADA and WHO) have not projected the influence of the glycemic level on fetal outcome.

Clarity in Labeling The Different Magnitude of Abnormal Glucose Intolerance on Pregnancy

Increasing maternal carbohydrate intolerance in pregnant women without GDM is associated with a graded increase in adverse maternal and fetal outcomes implying that fetal morbidity starts at a lower maternal glycemic level (< 140 mg/dl). A number of prospective and retrospective studies have substantiated the observation that the frequency of adverse fetal outcome increases with 2hr PG > 120mg/dl .

Surprisingly, taking care of these women had resulted in a better fetal outcome. Thus, the data is robust and indicates that 2 hr > 120mg/dl needs cognizance.

The term ‘Impaired Gestational Glucose Tolerance (IGGT)’ is used by few authors to indicate pregnant women whose 2 hr PG is > 120mg/dl but below 140 mg/dl. . It may be appropriate to use the term ‘Decreased Gestational glucose tolerance (DGGT)’ instead of impaired gestational glucose tolerance.

The use of the term ‘Decreased’ is appropriate as it implies only ‘Low’ whereas the term ‘Impaired’ means both high and low. Further, quiet frequently we come across, labeling any abnormal value in the OGTT not meeting the diagnostic criteria of GDM as IGT. The use of this term ‘IGT’ during pregnancy may be confusing, as this terminology is also being used in non pregnant adult with 2 hr PG > 140mg/dl.

This level is also applied to diagnose GDM by WHO criteria. Hence it may be prudent to label 2 hr plasma glucose value > 140 mg/dl as GDM

and a 2 hr plasma glucose value > 120 mg/dl as ‘Decreased Gestational Glucose Tolerance’ (DGGT).

The term IGT should not be used to denote any abnormal value during pregnancy. The figures suggested below are easy to remember.

With 75 gm OGTT (WHO criteria);

	In Pregnancy	Outside Pregnancy
2 hr = 140 mg/dl 2 hr = 120 mg/dl	Diabetes GDM (2 hr = 200 mg/dl DGGT	Diabetes IGT —

Gestational Weeks at Which Screening is Recommended

Screen timings: A) first at16th week of::B) Second screen : 24th – 28th week and finally C) around 32nd – 34thweek.20

Practically all the pregnant women should undergo screening for glucose intolerance. The usual recommendation for screening is between 24 and 28weeks of gestation. The recent concept is to screen for glucose intolerance in the first trimester itself as the fetal beta cell recognizes and responds to maternal glycemic level as early as 16th week of gestation. If found negative at this time, the screening test is to be performed again around 24th – 28th week and finally around 32nd – 34thweek.

The maternal metabolic adaptation is to maintain the mean fasting plasma glucose of 74.5 ± 11 mg/dl and the post prandial peak of 108.7 ± 16.9mg/dl.

This fine tuning of glycemic level during pregnancy is possible due to the compensatory hyperinsulinaemia, as the normal pregnancy is characterized by insulin resistance. A pregnant woman who is not able to increase her insulin secretion to overcome the insulin resistance that occurs even during normal pregnancy develops gestational diabetes. GDM recurs approximately in 50% of subsequent pregnancies. The future risk of developing diabetes for age gestational diabetic is twofold, if she becomes overweight. But maintaining ideal weight approximately halves the risk. The requirement of insulin in addition to diet to maintain euglycemic during the index pregnancy is also predictive of future diabetes.

The metabolic goals of pregnancy are
1) in early pregnancy to develop anabolic stores to meet metabolic demands in late pregnancy and
2) in late pregnancy to provide fuels for fetal growth and energy needs.
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Gestational Diabetes Mellitus (GDM) is defined as ‘carbohydrate intolerance with recognition or onset during pregnancy’, irrespective of the treatment with diet or insulin. The importance of GDM is that two generation is at risk of developing diabetes in the future. Women with a history of GDM are at increased risk of future diabetes, predominately type 2 diabetes, as are their children. The maternal health and fetal outcome depends upon the care by the committed team of diabetologists, obstetricians and neonatologists. A short term intensive care gives a long term pay off in the primary prevention of obesity, IGT and diabetes in the offspring, as the preventive medicine starts before birth.

GDM occurs when the woman’s beta cell function is notable to overcome the antagonism created by the anti-insulin hormones of pregnancy and the increased fuel consumption required to provide for the growing fetomaternal unit.-