TX:
Diet and exercise.
Insulin
Oral medications lack long-term safety data. But many people use it.
Treating GDM improves outcomes for both the mother and infant. These include:
-a decreased risk for operative delivery,
-large-for-gestational-age infants,
-shoulder dystocia, and
-maternal preeclampsia.
Tx doesn’t reduce risk of developing DM2.
“Clinicians who care for pregnant women need to be familiar with the diagnosis and monitoring parameters for gestational diabetes mellitus, as these help to determine the need for management strategies outside of diet and exercise. The goal is ≤95 mg/dL for fasting blood glucose, ≤140 mg/dL for 1-hour postprandial glucose, and ≤120 mg/dL for 2-hour postprandial glucose.”ABFM
“A history of gestational diabetes mellitus (GDM) is the greatest risk factor for future development of diabetes mellitus. It is thought that GDM unmasks an underlying propensity to diabetes. While a healthy pregnancy is a diabetogenic state, it is not thought to lead to future diabetes. This patient’s age is not a risk factor. Obesity and family history are risk factors for the development of diabetes, but having GDM leads to a fourfold greater risk of developing diabetes, independent of other risk factors (SOR C). It is thought that 5%–10% of women who have GDM will be diagnosed with type 2 diabetes within 6 months of delivery. About 50% of women with a history of GDM will develop type 2 diabetes within 10 years of the affected pregnancy.” ABFM critique
Read this article: Am Fam Physician 2015;91(7):460-467
Boards and Wards notes
30+ yo G2P2 s/p SVD, morbidly obese pt with GDM.
Prior to pregnancy, pt was on Metformin 500 BID and 60 units of Levemir.
When she got pregnant, she developed GDM on top of her chronic diabetes.
To keep her sugars down required:
Thirty minutes before breakfast:
100 units of Humulin N (NPH)
50 units of Humulin R (Regular insulin)
At lunch:
50 units of Lantus (Lantus QHS and QAM was considered by her Maternal Fetal Medicine high-risk OB physician but noon was chosen as best option).
Thirty minutes before 5:30 dinner (i.e. at 5:00pm)
45 Units of Humulin R
At bedtime:
50 units of Humulin N
*She didn’t use metformin during pregnancy.
With that much insulin, her fasting sugars were in the 68-70 range around 6:00am and she never had hypoglycemic episodes. Her sugars 1hr after lunch were in the 80s-90s. Her sugars 1hr after dinner were also normal.
Pt had a similar thing happen during her first pregnancy where she used similarly large amounts of insulin to control her sugars.
She checked her blood sugars 4 times daily: Fasting plus 1 hour after every meal.
On PPD# 1, pt had an episode of BS in low 60s. Received D5 and sugars were raised to 75.
Patient was placed on:
15 units of Lantus
Metformin 500mg BID (Renal function was evaluated before metformin was started, see new guidelines).
SSI resistant / medium
Pt did well. Her sugars were all normal with above regimen. She did not use the sliding scale insulin and was discharged to f/u with OB in 6 weeks. Lantus will be titrated as needed.
References
Diabetes 2007;56(12):2990-2996. A 20-year prospective study of childbearing and incidence of diabetes in young women, controlling for glycemia before conception.
Am Fam Physician 2009;80(1):57-62. Diagnosis and management of gestational diabetes mellitus.
Am Fam Physician 2015;91(7):460-467. Screening, diagnosis, and management of gestational diabetes mellitus.
Effects of treatment in women with gestational diabetes mellitus: Systematic review and meta-analysis. BMJ 2010;340:c1395.
Committee on Practice Bulletins—Obstetrics: Practice bulletin no. 137: Gestational diabetes mellitus. Obstet Gynecol 2013;122(2 Pt 1):406-416.
Glibenclamide, metformin, and insulin for the treatment of gestational diabetes: A systematic review and meta-analysis. BMJ 2015;350:h102.