What is Gestational Diabetes?
Insulin Resistance and obesity-linked Gestational Diabetes is a condition that develops in the third trimester of pregnancy and affects 4-12 % of all pregnant women. With Gestational Diabetes, the pancreas produces insulin but not enough to lower the mother’s blood sugar levels.
All Indian Pregnant women must get a Fasting and /or Random Bld Glucose check test with each pre-natal visit. If HbA1c is also done that will be a great value addition.
To determine if a woman has this condition, she should be tested immediately as soon as pregnancy is confirmed and between 22 and 26 weeks if she is at average risk i.e. has no history of prior Gestational Diabetes and is of regular weight. Women at higher risk should be tested earlier. A patient is considered high risk if she is obese, has glycosuria (glucose in the urine) or has a personal or family history of Gestational Diabetes or is pregnant second time onwards.Practically BEING INDIAN MAKES A FEMALE A HIGH RISK CASE for Gestational Diabetes!
Pregnancy and Obesity
Women who are overweight before they become pregnant are most at risk for this disorder. The best way to avoid it is to lose weight before becoming pregnant via a low Glycemic Index (GI) diet and regular exercise. Gestational Diabetes usually disappears after pregnancy, but it can lead to the development of Pre- and Type 2 Diabetes years later.
How GDM Develops ?
As a baby grows, it is supported by the placenta. Hormones from the placenta help the baby develop but these hormones can also block the action of insulin in the mother’s body. Normally this is Nature’s way to create a situation wherein fetus gets Priority for nutrition but when exaggerated this may convert to the state of Gestational Diabetes.
This problem is called Insulin Resistance, which makes it hard for the mother’s body to use insulin in the normal way and requires her to need up to three times as much insulin as when she was not pregnant.
The process starts when the body is not able to make and use all the insulin it needs for pregnancy. Without enough insulin, glucose cannot leave the blood through the cell wall and be converted to energy. Glucose builds up in the blood to high levels, which is called hyperglycemia as explained earlier.
Gestational Diabetes affects the mother in late pregnancy, after the baby’s body has been formed and it is busy growing. Because of its late development, the GDM does not cause the kinds of birth defects which otherwise may develop in babies whose mothers had other forms of Diabetes before pregnancy.
Gestational Diabetes’ Effect on Babies
However, untreated or poorly-controlled Gestational Diabetes can hurt the baby. Although insulin does not cross the placenta, glucose and other nutrients do. So extra blood glucose gives the baby high blood glucose levels. This causes the baby’s pancreas to make extra insulin to get rid of the blood glucose. Since the baby is getting more energy than it needs to grow and develop, the extra energy is stored as fat.
This can lead to macrosomia, or a “fat” baby. Babies with macrosomia face health problems of their own, including damage to their shoulders during birth. Because of the extra insulin made by the baby’s pancreas, newborns may have very low blood glucose levels at birth and are also at higher risk for breathing problems.
Remember : A fat new born may not be a healthy baby !
Babies with excess insulin become children who are at risk for obesity and, later, adults who are at risk for Pre- and Type 2 Diabetes. Pre-Diabetes is a reversible condition that occurs when a person’s blood glucose levels are higher than normal but not in the range of irreversible Type 2 Diabetes.
How to prevent GDM ?
The best way of preventing Gestational Diabetes is to have a more active lifestyle and not be overweight before pregnancy. But if it does develop, early treatment is required because the disorder can hurt both mother and baby. The treatment aims to reduce and maintain normal blood glucose levels to those of pregnant women. It includes special meal plans and scheduled physical activity, though pregnancy is not a good time for rigorous exercise.
Treatment for Gestational Diabetes helps lower the risk of a cesarean section birth that very large babies may require. While the disorder usually goes away after pregnancy, your chances are 2 in 3 that it will return in future pregnancies.
In a few women, however, pregnancy uncovers Type 1 or reversible Pre-Diabetes, which, if left unchecked, can lead to Type 2 Diabetes, a disorder that must be managed throughout one’s lifetime and may require daily insulin. It is sometimes difficult to diagnose whether these women have Gestational Diabetes or have just started showing their Diabetes symptoms during pregnancy.
Gestational and Type 2 Diabetes – is there a A Link?
As mentioned, many women who have Gestational Diabetes go on to develop Type 2 Diabetes years later. There seems to be a link between the tendency to have Gestational and to develop Type 2 Diabetes, both of which involve Insulin Resistance.
Once Gestational Diabetes has disappeared after giving birth, some basic changes in lifestyle can help prevent the later onset of Insulin Resistance. If neglected, this latter condition may lead to Pre-Diabetes and a severely increased risk of Type 2 Diabetes. These lifestyle changes are:
Losing weight – if you’re 20% over your ideal body weight, you’re at risk. Losing even a few pounds can help you avoid developing Type 2 Diabetes. ♦ Making healthy food choices – follow simple daily guidelines, ♦ like eating a variety of foods including fresh fruits and vegetables, avoiding refined carbohydrates (e.g. sugar, bread, bagels, pasta, cookies, crackers, chips, soda and candy), minimizing intake of complex carbs (e.g. brown rice, whole wheat pasta and whole wheat bread) and keeping a close eye on your portion size. Healthy eating habits can help prevent Type 2 Diabetes and a host of other Insulin-Resistance-related health problems like the cluster of cardiovascular diseases called Metabolic Syndrome (Syndrome X) and Polycystic Ovarian Syndrome (PCOS), a hormonal imbalance which is a leading form of female infertility. All Insulin Resistance-related conditions are increased risk factors for Cardiovascular Disease, which can lead to a heart attack or stroke in both sexes. ♦ Exercising – regular exercise allows your body to use glucose without extra insulin. This helps combat Insulin Resistance, a root cause of Pre-Diabetes leading to Type II Diabetes. But always check with your doctor before starting an exercise regime. Pregnancy is not a good time to either start or pursue strenuous exercise. The ideal aim should be to lose weight and reach a healthy level through regular exercise before becoming pregnant.
Managing The Problem of GDM
Identify High Risk Cases
(i) All Asians,
(iii) With Family History
(iV) Twin Pregnancy
(v) Obese,Age >25 yrs’ past history of GDM
(vi) PCOS,prev. large babies
Low Risk• White race AND • Age < 25 years AND • Weight normal before pregnancy AND • No history of abnormal glucose metabolism AND • No history of poor obstetric outcome- You can see that practically all Indian Females are High Risk cases for GDM
1. Screen and Diagnose: a. All women (other than those at special risk) have a 50 g non-fasting glucose challenge test (GCT) performed at 24 – 26 weeks. If the 1-hour plasma glucose is = 140 mg%, they will be recalled to have an oral glucose tolerance test. I place the cut-off at 130 mg % for Indian females. b. The GTT is performed after a 10-12 hour fast. The fasting plasma glucose measured, and then 75g glucose solution is drunk in not more than 5 minutes, and then 1 hourly plasma glucose is measured. Patients may not smoke, eat nor drink anything other than water during the test, and should not perform any exercise. Gestational diabetes (GDM) is defined by any of the two levels above the limits given below: Abnormal Values: At F : > 092 mg/dl;
At 1H: >180 mg/dl;
At 2H: >153 mg/dl;
OR with or without fasting if a pregnant lady shows Blood Glucose of more that 140 mg % TWO hours after ingestion of 75 G of Glucose,one can assume that Gestational Diabetes is present.
Also note that ½ Hrly Testing is no more recommended.
STAGE THREE :CLINICAL INTERVENTION :
D. First Visit After Diagnosis1. Education- most crucial. a. All the women with GDM are seen initially by the diabetes educator and receive the following information:
I. Importance of GDM
II. Education in home glucose monitoring
III. Initial diet and exercise advice
IV. Long-term follow-up
NOTE: Women at special high risk of should be tested with a GTT in the first instance. If a GTT is performed before 24 weeks and if normal, should be repeated at 28 weeks. E. )Insulins To be Used : Human insulin (Regular/Pre-Mixed) Aspart and Lispro all three can be used ,as different combinations ,depending upon the glycemic profile of your patient Insulin Levemir is also now favored as basal Insulin
At the Diabetes Clinic
a. All women with GDM are seen at the diabetes clinic by an obstetrician
b. All women with GDM will be seen by the dietitian and have appropriate dietary advice.
C. Till the glycaemic control is made, women will also be seen by the diabetologist.
3. Investigations: Routine
b. Urea, creatinine, uric acid and electrolytes LFT,TFT. c. Random plasma glucose.
d. Ultrasound examination at diagnosis & at 30 weeks for growth. This should be repeated as clinically indicated, or at 36 weeks if the initial estimated fetal weight is > 80th percentile.
G.)Achieving Glycaemic Control & Defining TARGETS
a. All women with GDM will perform home blood glucose monitoring (SMBG), initially 4 times each day before breakfast and 2 hours after each meal. This may be reduced if the values are normal.
b. The target levels are = 90-95 mg % fasting and < 120 mg% at 2 hours after meals. or < 140 mg% at 1 Hr after meals. ; c. ASSESS WEEKLY ; d.Occasionally, it may be appropriate to commence insulin on the basis of developing fetal macrosomia.
H.) Subsequent Visits & Follow-up :
1.Frequency of visits
a.Three-weekly until 28 weeks, then 2-weekly until 38 weeks then weekly until delivery if not on insulin. Women receiving insulin should be seen weekly from 34 weeks.
b.IMP: Visit frequency should be increased if there are other complications, such as:
i.Hypertension pre-existing or pregnancy-induced.Retinal or Renal Problems also need more frequent visits,
iii.Intrauterine growth restriction.
iv.Poor glycaemic control
a.Ultrasound examination for growth as above. More frequent ultrasound examination, including umbilical artery blood flow measurement, may be indicated with the above complicating factors.
b.Cardiotocography should be performed weekly from 40 weeks gestation in the absence of complicating factors.
c.Earlier and more intensive (more frequent CTG, Doppler flow studies, biophysical profiles) fetal monitoring may be indicated in the presence of the above complications
In close association with your Diabetologist & Obstetrician
a. In patients with optimal glycaemic control and no complicating factors (see above) delivery should be considered at 40-41 weeks, with the method depending on obstetric factors. Insulin by itself is not an indication for earlier delivery. If an elective Caesarean section is to be performed, this should be at 39 weeks.
b. Patients with one of the complicating factors mentioned above should be delivered at 38-39 weeks, or earlier if indicated.
c. A very tight control around delivery saves the new born from landing in an ICU.
2. Method-Suggested is:
a.If the estimated fetal weight at the time of delivery is < 4,000 g, vaginal delivery is usually appropriate unless there are other obstetric indications for Caesarean section. b.If the estimated fetal weight at the time of delivery is > 4,250 g, elective Caesarean section should be strongly considered because of the risk of shoulder dystocia. c. If the estimated fetal weight at the time of delivery is 4,000 – 4,250 g, the decision about the route of delivery should be discussed with the patient taking into account the risks for the particular patient.
J.)Follow-up <- As much as 47- 50 % cumulative risk of developing Diabetes at 5 yrs and 16 – 20 % yearly risk of developing Impaired Fasting Glucose /Impaired Glucose tolerance after GDM, makes the follow-up GTT a very important tool to screen out patients who may develop DM type 2.
a.This GTT should be performed 6-8 weeks postpartum. The GTT is a standard 75 g GTT using WHO, non-pregnant criteria.
b.Women with an abnormal GTT (diabetes, impaired glucose tolerance or impaired fasting glycaemia) should be reviewed by the diabetes physician. They should have annual GTTs thereafter.
e.Women with a normal postnatal GTT should be advised about a healthy lifestyle, and to have a GTT every 2 years.
MNT: Medical Nutrition therapy for GDM is a mandatory component.