Managing Gestational Diabetes
Cynthia V. Brown, RN, MN, ANP, CDE
Southeastern Endocrine & Diabetes
Managing Gestational Diabetes
• The management of gestational diabetes is
necessary for a healthy baby and mom.
• Managing this disorder well is a….
Richard Shafer:
…CHALLENGE!!!
Definitions
Gestational Diabetes
Pre-gestational Diabetes
Gestational diabetes...
• May have its’ onset or be first recognized
during pregnancy
• Diabetes may have previously existed but
not diagnosed
Pre-gestational diabetes...
• May be present and undiagnosed
• Evolving
• Already present and under treatment
Why is this important?
• Pre-existing diabetes at conception can
lead to congenital anomalies
• Gestational diabetes leads to macrosomia
and premature delivery
Congenital Malformations
• Cardiovascular: transposition, vsd, asd,
hypoplastic left ventricle, anomalies of the
aorta
• CNS: anencephaly, encephalocele,
meningomyelocele, microcephaly
Malformations...
• Skeletal: caudal regression, spina bifida
• GU: Potter syndrome, polycystic kidneys
• GI: tracheoesophageal fistula, bowel
atresia, imperforate anus
First Trimester Miscarriages
40
Percent of women
35
30
25
20
15
10
5
0
<6.05
6.05-7.2
7.2-8.3
HbgA1c
8.3-9.5
>9.5
Complications by Trimester
• First
– Still births
– Miscarriages
– Congenital defects
• Second and Third
– Hyperinsulinism
– Macrosomia
– Delayed lung development
Complications...
• Delivery
–
–
–
–
Injuries
RD
Pregnancy loss
Neonatal hypoglycemia
Hormonal Influences
Decreased glucose levels
• Due to passive diffusion to fetus
• Causes hypoglycemia, even in non-diabetic
patients
• Greatly decreases insulin need in first
trimester
Accelerated starvation...
• Due to glucose diffusion
• Leads to elevated ketone production
• Unsure if this hurts baby or not
• Use as guide for increased calories
Decreased maternal alanine
• Gluconeogenic amino acid
• Results in further lowering of FBS
Counterregulatory hormones
• Suppressed responses to hypoglycemia
• Study found BS as low as 44 did not elicit a
response
• Level at which glucose & GH released 5-10
mg/dl lower in pregnant women with Type 1
DM
• Hypoglycemia aggravated by lower intake
due to AM sickness
Prolonged hyperglycemia
• Enhances transplacental delivery of
glucose to fetus
• Resistance to insulin x 5-6 hours PC
• Resistance related to several anti-insulin
hormones
• Results in hyperglycemia
Hormones affecting blood sugar
•
•
•
•
•
•
•
Insulin
Glucagon
Epinephrine
Steroids
Growth hormone
Progesterone
Human placental lactogen
Peak Times of Hormonal Activity
•
•
•
•
•
•
Hormone
Estradiol
Prolactin
HCS
Cortisol
Progesterone
Onset
32 d
36 d
45 d
50 d
65 d
Peak Potency
26 wk
1
10 wk
2
26 wk
3
26 wk
5
32 wk
4
Risk Factors
•
•
•
•
Over 25 years of age
Family history of Type 2 diabetes
Obesity
Prior unexplained miscarriages or
stillbirths
• History GDM or baby >10 pounds
• PCOS
Dietary Modifications
•
•
•
•
•
•
•
Decrease carbohydrate content
Frequent small feedings
Small breakfast meals
Bedtime snacks
No > 10 hours overnight fast
NO JUICE
Adequate calorie intake
Blood Sugar Goals
•
•
•
•
•
Fasting:
Premeal:
One-hour post-prandial:
Two-hour post-prandial:
2AM-6AM:
< 90 mg/dl
60-90 mg/dl
<120 mg/dl
<120 mg/dl
60-90 mg/dl
Estimated insulin needs
•
•
•
•
•
•
Prepregnancy
Weeks 2-16
Weeks 16-26
Weeks 26-36
Weeks 36-40
Postpartum
0.6 U/kg
0.7 U/kg
0.8 U/kg
0.9 U/kg
1.0 U/kg
<0.6 U/kg
When to Start Medications
• Allow 1 week of dietary changes
• Continue with diet if BS in target
• First week with 2 elevated sugars, insulin
starts
• Frequent testing so as not to miss elevation
• Anticipate need increasing
• Do not be afraid!
Medications
• Sulfonylureas:
–
–
–
–
Glyburide typically used
Anecdotal evidence
Not very effective
Unable to achieve higher insulin levels for
meals
– No long-term studies for safety
Medications
• Insulin:
– NPH:
•
•
•
•
BID dosing
Can start only at HS if FBS elevated
Long history of safety
Inconsistent absorption
Medications
• Lantus:
– 24 hour coverage
– Sometimes hard to affect dawn rise without
nocturnal low BS
– Does not rise to meet meal-time rise of BS
Medications
• Insulin analogs:
–
–
–
–
Humalog, Novolog, Apidra
Very rapid acting
Very effective pre- and post prandial
Less risk of hypoglycemia
Medications
• Regular insulin:
– Slower onset
– Longer duration
– May be necessary in those who do not want to
take as many injections
Insulin Dosing During Labor
• Need decreases dramatically
• BS must be perfect in 72 hours prior to
delivery
• May not need insulin during labor
• Type 1 needs only basal insulin with PRN
supplementation
Postpartum
•
•
•
•
Continue periodic testing
Aim to lose weight
Glucose challenge @ 6 wk check
Breast-feeding lowers BS, leads to
hypoglycemia
Managing Gestational Diabetes
THANK YOU!
Cynthia V. Brown, RN, MN, ANP, CDE
Southeastern Endocrine & Diabetes