Gestational Diabetes Mellitus

Gestational Diabetes Mellitus (GDM) occurs in women who are pregnant and will often appear sometime in their 24th to 28th week of pregnancy. GDM, like other forms of diabetes, is glucose intolerance. Gestational Diabetes will affect approximately 3% of Canadian women during their pregnancies (1). This form of diabetes only occurs during pregnancy and ends after childbirth.

Women at risk of GDM may display mild forms of the following signs and symptoms including:

· Increased thirst (polydipsia)

· Increased urination (polyuria)

· Weight loss in spite of increased appetite (polyphasia)

· Fatigue

· Nausea and vomiting

· Frequent infections including those of the bladder, vagina, and skin

· Blurred vision

Often these mild signs and symptoms are masked by the natural symptoms of pregnancy, such as fatigue, increased appetite or morning sickness (nausea and vomiting): which can lead to weight loss. In some cases women may have no discernable signs or symptoms. Instead, women should be aware of their risk factors, which include:

· A previous diagnosis of GDM

· 35 years +

· Obesity

· A history of polycystic ovary syndrome

· Hirsutism (excessive body and facial hair)

· Acanthosis Nigricans (a skin disorder characterized by the appearance of darkened patches of skin)

· Being a member of a population considered to be at high risk for diabetes, including women of Aboriginal, Hispanic, South Asian, Asian or African descent. (2)

Unlike other forms of diabetes where insulin is lacking, women with Gestational Diabetes have abundant amounts of insulin. But, the effect of their insulin is blocked by a variety of other hormones made in the placenta. Hormones such as estrogen, cortisol, and human placental lactogen (HPL) have a blocking effect on insulin. This blocking effect usually begins about 20 to 24 weeks into pregnancy. The more the placenta grows, more hormones are produced and the insulin resistance becomes even greater. In most women the pancreas is able to make additional insulin and compensate for the blocking effects of the placenta’s hormones. Gestational Diabetes occurs when the pancreas cannot make enough insulin to compensate for the blocking affects. When insulin is not produced glucose is no longer delivered to the cells in the body.

Gestational Diabetes Kelli Weidenborner

The glucose then stays within the blood and within the extra-cellular fluid and this can lead to the following symptoms associated with GDM:

Polydipsia: due to elevated blood sugar levels water is osmotically attracted from inside the cell into the extracellular space resulting in cellular dehydration and stimulation of thirst by the hypothalamus.

Polyuiria: hyperglycemia acts as an osmotic diuretic. The excess glucose cannot be filtered by the glomerus in the kidneys and isn’t reabsorbed by the tubules. This excess glucose attracts water and therefore large amounts of water are lost in the urine.

Polyphasia: depletion of cellular stores of carbohydrates results in the cellular starvation and increase in hunger. The lack of carbohydrates may also lead to ketoacidosis as the body starts to use alternate