Gestational diabetes is
a condition where the blood sugars are elevated during pregnancy. This happens
due to hormonal changes occurring during pregnancy. Hormones produced by the
placenta help in providing more nutrients to the growing fetus. Some hormones
act against insulin action and prevent the development of hypoglycaemia in the
mother. To counteract this excess production of hormones against insulin the
mother’s body produces more insulin. In most women these changes are not
prominent enough to cause diabetes. Women are most vulnerable during the third
trimester of pregnancy. In case the mother is not able to produce considerable
amount of insulin to counteract the effect of these hormones they end up in
what is called Gestational Diabetes.
So
What? Why should we worry? Will it not go away after pregnancy?
Diabetes affects in
various ways.....
It can result in
Birth defects affecting
major organs like brain and heart
Miscarriage
Large baby leading to
difficult labor
May need caesarean section.
The baby, once
delivered may end up in severe hypoglycaemia due to increased amounts of
insulin in the system.
Who
all can develop Gestational Diabetes ???
- Overweight
- High risk ethinicity
- Patients in Prediabetes
- Family history of diabetes
- History of giving birth to large babies.
- Previously giving birth to a stillborn baby
- Having gestational diabetes with a previous pregnancy
- History of polyhydramnios
- Many women who develop gestational diabetes have no known risk factors.
How
do we diagnose this condition??
High risk women should
be screened for gestational diabetes as early as possible during their
pregnancies.
All other women need to
be screened between the 24th and 28th week of pregnancy.
The best test available
is the oral glucose tolerance test. This test involves quickly drinking a
sweetened liquid which contains calculated amount of sugar. Then blood samples
are collected at an interval of one hour and 2 hours. 2 hour value more than
140mg/dl is considered indicative of gestational diabetes.
Let’s
talk about the good news...
A simple solution to
prevent complications associated with
gestational diabetes is by screening of pregnant women for gestational diabetes
using Oral Glucose Tolerance Test and to keep the glucose level within prescribed levels — fasting plasma glucose 90 mg/dl and
two hours after meal — 120 mg/dl. The earlier ( 1999) WHO guidelines insisted a
pregnant woman to come fasting for testing. The plasma glucose level was tested
two hours after 75 mg of glucose was given to a woman. If the value was between
140 mg/dl and 199 mg/dl, the pregnant woman was diagnosed as having gestational
diabetes. “The revised WHO guidelines retain the same value but the biggest
difference is that women need not come
fasting for testing,” The rest of the procedure remains the same. The
non-fasting plasma glucose level is tested two hours after 75 gm of glucose is
given to the woman. “If the two-hour plasma glucose measurement is between 140
[mg/dl] and 199 [mg/dl], she is diagnosed as GDM
WHO’s non-fasting
plasma glucose testing recommendation makes testing easy for pregnant women.
The non-fasting test is patient-friendly and causes the least inconvenience to
pregnant woman. The single-step procedure is easy to follow, economical, simple
and evidence-based. This also reduces the incidence of nausea associated with
intake of sweet liquids on empty stomach.
Screening for
gestational diabetes should be done in the first trimester (at least by 12-16
weeks). Earlier, the screening was done at 24-28 weeks. The reason why WHO does
not recommend the late screening (24-28 weeks) is because by the 12 week, the
beta cells develop in the fetal pancreas. And these fetal cells respond to
the elevated maternal glucose levels. As a result, when the fetus gets more than
the required amount of nutrition (glucose), it gets converted into fetal fat;
the fetus thereby gains weight and becomes big. So, the earlier the screening
of pregnant women, the better the fetal outcome.
Dr.Riyaz Sheriff
Consultant Diabetologist
