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Free Patient educational Materials (brochures, food guides,  weight gain grids, etc.) available at:
 California Diabetes and Pregnancy Program CDAPP Sweet Success Resource & Training Center

Definition of Diabetes [44]

An abnormally high amount of sugar (glucose) in the blood . Overt diabetes may be diagnosed if any of the following criteria are present

  • Fasting* plasma glucose (FPG) greater than or equal to 7 mmol/L (126 mg/dl )
  • Hemoglobin A1 C (A1C) is 6.5% or higher,
  • Random plasma glucose greater than or equal to 11.1 mmol/L ( 200 mg/dl ) in a patent with symptoms of hyperglycemia or in hyperglycemic crisis. Should be confirmed by FPG or A1C
  • 2 hour plasma glucose greater than or equal to 11.1 mmol/L (200 mg/dL) during an 75 g OGTT as described by the WHO. Results should be confirmed on repeat testing if hyperglycemia is equivocal .

* Fasting= no caloric intake for at least 8 hours.

Classification of Diabetes [44]

  • Type 1 diabetes mellitus (T1DM):  Inability to produce insulin caused by autoimmune destruction of pancreatic β-cells. T1DM patients have a propensity to develop ketoacidosis. Previously termed insulin-dependent diabetes or juvenile diabetes.
  • Type 2 diabetes mellitus (T2DM)   Insulin resistance in muscle and liver with  β-cell failure leading to inadequate insulin secretion . Previously termed noninsulin-dependent diabetes .
  • Other: Diabetes due to other specific causes such as cystic fibrosis or drug induced (glucocorticoids).
  • Gestational diabetes mellitus (GDM) : Carbohydrate intolerance with onset or recognition during pregnancy that is not overt diabetes.

Diagnosis of Hyperglycemia in Pregnancy

Diagnosis of Gestational Diabetes Mellitus (GDM) [1-4]

The American College of Obstetricians and Gynecologists supports NIH recommendations and recommends that before the testing approach and diagnostic criteria for GDM are changed, implications of such changes should be studied.

1 Hour (50 g) Oral Glucose Tolerance Test
2 Hour (75 g) Oral Glucose Tolerance Test
3 Hour (100 g) Oral Glucose Tolerance Test

Self-Monitoring of Blood Glucose [7]

Blood sugar ranges recommended during pregnancy by the California Diabetes and Pregnancy Program  :

Time Glucose Value
Fasting 6 0 to 89 mg/dl ( 3.3 to 4.9 mmol/L )
Premeal /bedtime/ overnight 60 to 90 mg/dl ( 3.3 to 5 mmol/L )
Postprandial 1 hour from start of meals 100 to 129 mg/dl ( 5.6 to 7.2 mmol/L )

Women with type 1 diabetes or type 2 diabetes on multiple daily Insulin Injections  (MDI) should test their fasting, premeal, one hour after start of meals, bedtime, and occasional 3 AM blood sugars

Women with ype 2 diabetes on oral medications should test their fasting, one hour after start of meals,
and bedtime blood sugars [1,7]

Blood sugar ranges recommended during pregnancy by the  American Diabetes Association  [44]

Preprandial less than or = 95mg/dL (5.3mmol/L) and either
○ One-hour postmeal less than or = 140 mg/dL (7.8 mmol/L) OR
○ Two-hour postmeal less than or = 120 mg/dL (6.7 mmol/L)

For women with preexisting type 1 diabetes or type 2 diabetes who become pregnant, the following are recommended
as optimal glycemic goals if they can be achieved without excessive hypoglycemia :
○ Premeal, bedtime, and overnight glucose 60–99 mg/dL (3.3–5.4 mmol/L)
○ Peak postprandial glucose 100–129 mg/dL (5.4–7.1 mmol/L)
○ A1C <6.0%


Example of a prescription for glucose test strips :

Name of Blood Glucose Strip
Use (4 to 10) of strips per day
# 200 strips
Refills: 6 months
Patient is pregnant


Key components in the management of diabetes are diet and exercise.
Click here for diabetic exchange list.

Anti-Diabetic Agents

Patients with diabetes prior to pregnancy, a history of diabetic ketoacidosis, liver disease, or a fasting blood sugar greater than or equal to 140 mg/dL at diagnosis are treated appropriately with insulin [8-12 ].

The ACOG recommends when pharmacologic treatment of GDM is indicated either insulin or oral medications (metformin or glyburide)   can be an appropriate first-line therapy [1]. However, meta-analysis found when compared to insulin, glyburide was associated with higher neonatal birth weight and increased incidence of neonatal hypoglycemia [14,15],

Oral hypoglycemic agents (OHA)

Glyburide (Micronase® )  [13].
Oral blood-glucose-lowering drug of the sulfonyl- urea class . Glyburide stimulates release of of insulin from the pancreas .Glyburide crosses the placenta [26,27]

  • Used as an adjunct to diet to lower the blood glucose in patients with non-insulin-dependent diabetes mellitus [1,7].

      Starting dose 1.25 mg to 2.5 mg PO daily 60 minutes before meals to control postprandial sugar. Use lower dose for women with weight less than 200 pounds..
      May give at 10 to 11 PM  to control fasting blood sugar.
      May increase by 1.25 to 2.5 mg every 3 to 7days until blood sugar controlled or a maximum daily dose of of 20 mg.

    Should not be used in patients who report a sulfa allergy [1]. Potential clinical adverse effects associated with the use of glyburide are hypoglycemia and allergic reaction.

(1.25, 2.5, and 5 mg tablets)

Use in Breastfeeding: Limited data indicate that the levels of glyburide in milk are negligible .  Appears to be compatible with breast-feeding. However, the  the baby  should be monitored for signs of hypoglycemia [16,17].

Metformin (Glucophage® ) [21].
Oral blood-glucose-lowering drug of the biguanide class  Metformin decreases glucose production by the liver, decreases intestinal absorption of glucose, and improves insulin sensitivity by increasing peripheral glucose uptake and utilization . Metformin crosses the placenta[ 28]

  • Used as an adjunct to diet to lower the blood glucose in patients with non-insulin-dependent diabetes mellitus [14,15]

    500 mg once or twice daily given with meals. Usually given with breakfast and dinner. May increase in increments of 500 mg every 3 to 7 days  up to a total of 2500 mg per day.

If a woman is taking metformin prior to her pregnancy or at the first prenatal visit, it is recommended she continues to take metformin [1,7]. Women taking metformin for polycystic ovarian syndrome (PCOS) may benefit from continuing  to take metformin throughout the pregnancy [19,20]

Lactic acidosis is a rare, but serious, metabolic complication that can occur due to metformin accumulation during treatment.  Metformin is contraindicated in renal disease or renal dysfunction (e.g., as suggested by serum creatinine levels or abnormal creatinine clearance), which may also result from conditions such as cardiovascular collapse (shock), acute myocardial infarction, and septicemia  Discontinued prior to major surgery, or radiological studies involving contrast materials.

(500, 850, and 1000 mg tablets)

Use in Breastfeeding:  Metformin levels in milk are low and infants would receive less than 0.5% of their mother's weight-adjusted dosage. Use with caution in premature infants and infants with renal disease [22-25].



Insulin is an anabolic  hormone with a  molecular weight of 5808 Da. Maternal insulin does not cross the placenta unless it is bound to IgG antibody [29].  Insulin is produced in the pancreas and is secreted in response to increased blood glucose and amino acids following ingestion of a meal. Insulin signals the cells (primarily skeletal muscle) to increase their uptake of glucose, suppresses lipolysis, acts on the liver to store glucose as glycogen, and inhibits glucagon secretion thereby  preventing glucagon from releasing glucose from the liver.

Synthetic "human" insulin is  manufactured using recombinant DNA technology.  Doses of insulin are measured in units. U-100 insulin contains 100 units/mL. The most commonly used types of insulin during pregnancy are regular insulin and NPH.  Neutral Protamine Hagedorn , NPH, is named after one of its developers the physician Hans Christian Hagedorn who discovered that combining a suspension of crystalline zinc insulin with protamine could prolong the duration of action of the insulin.  Insulin aspart , insulin lispro, insulin detemir, and insulin glargine are human insulin that have had their chemical composition slightly altered to influence their onset and duration of action. Allergy to recombinant human insulin preparations is uncommon , and more likely due to components including zinc, protamine, and meta-cresol [32].

The graph below illustrates the differences in the onset and duration of action for various types of insulin.


When compared to treatment with regular insulin, rapid-acting insulin analogs, lispro and aspart show better postprandial control, less hypoglycemia and a trend towards reduction of preterm delivery. The California Diabetes and Pregnancy Program recommends  the rapid acting insulin analogs lispro and aspart, and NPH as the preferred insulins for pregnancy.  In addition, women on glargine and detemir should consider switching to intermediate acting NPH or to a continuous subcutaneous insulin pump before becoming pregnant  [7].


In general, when a longer-acting insulin (e.g. NPH insulin isophane suspensions) is mixed with short-acting or rapid acting-soluble insulin (e.g., regular), the short-acting or rapid acting insulin should be drawn into the syringe first. Insulin glargine must NOT be diluted or mixed with any other insulin or solution The subcutaneous tissue of the abdomen is preferred site for injection because absorption of the insulin is more consistent from this location than subcutaneous tissues in other locations. [30]

See Initial Insulin Calculator and Intensive Multiple Daily Injections (MDI)

Among the potential clinical adverse effects associated with the use of all insulins are hypoglycemia and hypokalemia.


Unopened insulin should be stored in a refrigerator between 2 and 8°C (36 and 46°F); it should not be placed in a freezer. After initial use a vial may be kept at temperatures below 30°C (86°F) for up to 28 days, but should not be exposed to excessive heat or sunlight.  Unused insulin should be thrown away after the expiration date. Insulin in a pump reservoir should be discarded after at least every 48 hours of use or after exposure to temperatures that exceed 37°C (98.6°F).


Insulin syringes are available in three barrel sizes 1mL (100 units), ½ mL (50 units) and 3/10 mL (30 units). Needles also come in different sizes

BD Micro-Fine™ IV Needle is a 28-gauge, 12.7mm (1/2") thin
BD Ultra-Fine™ Needle is a 30-gauge, 12.7mm (1/2") Thinner
BD Ultra-Fine™ Short Needle  31-gauge, 8mm (5/16") Thinnest needle

Insulin Pen Needle sizes
29 gauge, 31 gauge, or 32 gauge.
Insulin Pen Needle lengths
 4, 5, 6, 8, or 12.7 mm

Example of a prescription for syringes :

Syringe Size: 1 cc, ½ cc, 1/3 cc, or 1/3 cc with half-unit scale
Ultra-Fine™ Short Needle  31-gauge, 8mm (5/16")
Sig: 4 of syringes used per day
#  100:
Refills: 6 months

For information on safe disposal of needles, syringes, and other sharps in the community contact:


Rapid-acting Insulins- Onset 15 minutes

Insulin aspart [rDNA origin] injection (NovoLog® )
Insulin lispro, [rDNA origin] injection (Humalog®)
Insulin analogs. Onset 1 to 15 minutes , peak of action 1 to 2 hours, duration 4 to 5 hours [32]

  • Indicated in the treatment of patients with diabetes mellitus for the control of hyperglycemia.

    Give calculated dose subcutaneously 15 minutes before a meal.
    The algorithm below may used, but may need to be modified according to the patient population. [31]
    Preprandial or Bedtime Blood Glucose average for at least 3 consecutive days (mg/dl) Adjust dose of aspart (Novolog) units
    >180 +3
    160-180 +2
    140-159 +2
    120-139 +1
    100-119 maintain dose
    80-99 -1
    60-79 -2
    <60 -4

(100 Units per mL in 10 mL vials, 3 mL cartridges, or 3 mL Pens)

Short-acting Insulins- Onset 30 to 60 minutes

Regular insulin human injection, USP (rDNA origin)
(Humulin®  -R,
Novolin® -R)
Insulin. Onset 30 to 60 minutes , peak of action 2 to 3 hours, duration of action 5 to 8 hours [33].

  • Indicated in the treatment of patients with diabetes mellitus for the control of hyperglycemia.

    Give calculated dose subcutaneously 30 minutes before a meal.

(100 Units per mL in 10 mL vials)

Regular insulin human injection, USP (rDNA origin)
Humulin R (U-500) ® ,Concentrated)

Insulin. Onset 30 to 60 minutes , peak of action 2 to 4 hours, duration of action 6 to 8 hours

  • Indicated in the treatment of diabetic patients with marked insulin resistance (daily requirments more than 200 units)

    Give calculated dose subcutaneously 30 minutes before a meal.

(500 Units per mL in 20 mL vials)

Intermediate-acting, Basal Insulin- Onset 2 to 4 hours

Neutral Protamine Hagedorn (NPH) Human Insulin (rDNA origin) Isophane Suspension 
®  -N , Novolin® N)
Zinc insulin combined with the polypeptide protamine. Onset  2 to 4 hours, peak of action 4  to 10  hours, duration of action 10 to 16 hours

  • Indicated in the treatment of patients with diabetes mellitus for the control of hyperglycemia.

Give calculated dose alone or mixed with short or rapid acting insulin subcutaneously.

(100 Units per mL in 10 mL vials)

Long-acting, Basal Insulin- Onset

Insulin detemir [rDNA origin] injection
(Levemir® )[35]
Onset 1 to 3  hours, peak of action 4  to 14  hours (no true peak), duration of action 6 to 24 hours (dose dependent)

  • Indicated in the treatment of patients with diabetes mellitus for the control of hyperglycemia. Not recommended for treating diabetic ketoacidosis.

Give calculated dose alone . Do not dilute or mix with any other insulin or solution. Do not administer subcutaneously via an insulin pump, intramuscularly, or intravenously.

If converting from insulin glargine to LEVEMIR, the change can be done on a unit-to-unit basis. If converting from NPH insulin, the change can be done on a unit-to-unit basis. However, some patients with type 2 diabetes may require more LEVEMIR than NPH

(100 Units per mL in 10 mL vials,3 mL LEVEMIR FlexTouch ® )

Continuous subcutaneous insulin infusion (CSII) therapy- Insulin pump[34]

The American Association of Clinical Endocrinologists (AACE) considers suitabe insulin pump candidates to have  the following characteristics .

Women with type 1 Diabetes who do not reach glycemic goals despite adherence to maximum multiple daily injections of insulin especially if they have very labile diabetes , frequent severe hypoglycemia and/or hypoglycemia unawareness, significant “dawn phenomenon,” extreme insulin sensitivity , and in special populations (e.g. pregnant women , competitive athletes) or other patients who, after investigation and careful consideration, feel that CSII would be helpful in achieving and maintaining treatment targets

Women with insulin requiring type 2 Diabetes who satisfy any or all of the following: are C-peptide positive, but with suboptimal control on a maximal program of basal/bolus injections, have substantial “dawn phenomenon”, erratic lifestyle (e.g., unpredictable schedules), OR severe insulin resistance.

AACE also recommends "After delivery, the insulin pump infusion should be stopped temporarily to avoid hypoglycemia; once the blood glucose is >100 mg/dL, infusion should be resumed at the prepregnancy settings".

See Calculation of Initial Insulin Pump settings (AACE)
See Calculation of Initial Insulin Pump settings (Sweet Success)


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