Gestational Diabetes

Gestational diabetes occurs in 2-5% of all pregnancies and alomst always presents in the third trimester. Hyperglycemia present at <20 weeks gestation suggests preexisting diabetes mellitus and should be managed as such.

 

 

Causes and Risk Factors

 

Gestational diabetes may result from the production of placental hormones such as HPL or cortisol.

Risk factors include:

 

 

 

Signs, Symptoms, and Diagnosis

Screening should be done at 24-28 weeks GA for all pregnant females >25 or <25 with above-mentioned risk factors

 

  • history
  • physical exam
  • lab investigations
  • diagnostic imaging

History

Patients are typically asymptomatic

Physical Exam

Edema may be present.

 

Lab Investigations

Urinalysis shows glucosuria.

A glucose tolerance test is diagnostic, screened at 24-28 weeks gestation.

  • <7.8 mmol/L plasma glucose (PG) - normal
  • PG <7.8 and < 10.3 mmol/L - further testing required
  • > 10.3 mmol/L diagnostic

Diagnostic Imaging

Ultrasound can reveal polyhydramnios or an infant >90% size for GA.

 

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Pathophysiology

 

Anti-insulin factors lrpduced by the placenta, together with elevated maternal cortisol, leads to increased insulin resistance and hyperglycemia.

 

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Treatments

Tight glucose control should be sought, as it improved outcomes (ref).

 

A diebetic diet should be started, along with regular exercise and glucose monitoring 4x daily.

Insulin should be added if sugars are not controlled with lifestyle measures.

 

Periodic ultrasounds and NST should be done to monitor fetal growth. Induced labour at 39-40 weeks may be necessary if growth is accelerated.

 

Intrapartum insulin and dextrose should be given to maintain tight control.

 

 

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Consequences and Course

Over 50% of patients develop glucose intolerance later in life, with elevated rates of type II DM following in many cases.

 

Maternal complications

Fetal complications

 

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Resources and References