Gestational diabetes involves a metabolic change in pregnancy where the carbohydrate metabolism is changed due to a relative lack of insulin.
Gestational diabetes has occurred as a result of profound hormone changes during pregnancy. The question is whether this pregnancy related diabetes was pre-existing or whether it only came on with the pregnancy. Diabetes and pregnancy do not mix. The reason for this is that uncontrolled diabetes would lead to fetal abnormalities, if the diabetes had preexisted.
Once the organ development in the fetus has taken place by 10 to 12 weeks into the pregnancy, the particular danger of congenital defects is no longer there, but uncontrolled diabetes would now affect the growth of the fetus (thanks to www.nlm.nih.gov/medlineplus for this link).
Babies of mothers who have uncontrolled diabetes grow faster and for this reason are large babies at birth. This leads to a high Caesarian section rate with its possible complications. Other gestational diabetes complications are a higher rate of hypertension, premature labor, increased infection rates in mother and baby and neonatal hypoglycemia (= in the baby), particularly when prematurely born. Some of the malformations of the fetus associated with uncontrolled diabetes are: neural tube defects, congenital heart defect and other congenital malformations incompatible with life. This is the reason why gestational diabetes is usually followed by special centers (prenatal and neonatal) where prenatal genetic counseling and treatment is given.
Studies have shown that when careful follow-ups are done with gestational diabetes pregnancies, the outcome can be the same as with regular pregnancies. However, it takes a multi disciplinary team of experts to help a diabetic patient to prepare for pregnancy or to help the newly diagnosed gestational diabetic. A gestational diabetic diet is taught to the patient, which will normalize the sugar metabolism.
The goal is to reach the normal blood sugars in pregnancy. If the fasting blood sugars are in the range of 76 mg/dL ( 4.2 mmol/L) and the 2 hour postprandial (after meals) blood sugar tests are less than 120 mg/L ( less than 6.6 mmol/L), the baby will develop normally. The goal of the therapist is to use human insulin to regulate the carbohydrate metabolism and mimic the normal situation during pregnancy as closely as possible. In gestational diabetes in particular there is no room for hypoglycemic attacks from accidental insulin overdosage as this could lead to death of the fetus in the uterus.
To avoid this from happening, the patient and the family should be instructed how to inject glucagon (the natural pancreatic hormone to balance insulin) subcutaneously. This is only necessary when the woman with gestational diabetes is in a state of confusion or unconsciousness and her blood glucosometer reading done by a relative is less than 40 mg/dL ( 2.2 mmol/L ).
The neonatologist will teach the patient how to keep the blood sugar levels from fluctuating too much (avoiding highs and lows) and at the same time to keep the hemoglobin A1C levels below 8% (better even in the 6% to 7% range).
This way malformations and complications can be kept at a minimum. All this makes it very clear that the patient needs to be followed closely by an aggressive treatment team who will teach the patient how she can keep her diabetes controlled. See your doctor and ask for a referral to such a multi disciplinary diabetes team.
1. MT Kailasam et al. J Hypertens 2000 Nov 18(11): 1611-1620.
2. G Chinetti et al. Inflamm Res 2000 Oct 49(10): 497-505.
3. St. Paul’s 46th Annual Cont. Med. Educ. Course for Prim. Phys., Nov. 14-17, 2000. Dr. David Thompson, Div. of Endocr., Vancouver Hosp. and UBC.
4. B J Goldstein Int J Int Pract 2000 Jun 54(5): 333- 337.
5. M Maghnie et al. N Engl J Med 2000 Oct 5;343(14): 998-1007.
6. E Albertazzi et al. J Am Soc Nephrol 2000 Jun 11(6):1033-1043.
7. M Funk et al. American Journal of Emergency Medicine Vol.19,No.6, Oct.2001, W. B. Saunders Company
8. Ferri: Ferri’s Clinical Advisor: Instant Diagnosis and Treatment, 2004 ed., Copyright © 2004 Mosby, Inc.
9. Rakel: Conn’s Current Therapy 2004, 56th ed., Copyright © 2004 Elsevier