妊娠糖尿病之診斷與治療

懷孕婦女中約有百分之五受到糖尿病的困擾，其中又以妊娠糖尿病（gestational diabetes mellitus, GDM）占多數。懷孕期間持續的高血糖，對產婦、胎兒或是新生兒都會造成危險；此外孕婦罹患妊娠糖尿病，也會增加其後一生罹患糖尿病的風險。因此，血糖控制對於懷孕婦女非常的重要。針對妊娠糖尿病的治療，仍建議以生活習慣的改變為起始，包含體重控制、飲食、運動及自我血糖監測。當生活習慣改變無法達到血糖控制目標，則必須合併降血糖藥物治療，如胰島素或是口服降血糖藥物。胰島素因其分子量大，一般認為幾乎不通過胎盤，目前為首選治療妊娠糖尿病的藥物。但是，胰島素必須以皮下注射，對於使用者而言相對不方便。口服降血糖藥物一直以來被認為有致畸胎的可能性，所以並不建議使用在懷孕婦女。但是，近來亦已有研究顯示，口服降血糖藥物中的部分藥品，如glyburide、metformin 及acarbose，對於孕婦及胎兒使用安全的疑慮相對低，可考慮在胰島素治療仍無法有效控制血糖後作為合併治療，或是病患本身無法使用胰島素時，作為胰島素之替代療法。至於其他口服降血糖藥物，在沒有更新的文獻證明前，建議避免使用於懷孕婦女。此外，懷孕對於生理狀態有非常大的影響，故不論是胰島素或是口服降血糖藥物，均可能會影響藥品於體內的藥物動力學模式，因此，在建立妊娠糖尿病的藥物治療計畫時，也需將此納入考量。本文回顧關於妊娠糖尿病的監測及治療，並說明懷孕對於藥物動力學的影響。

Approximately 5% of all pregnancies are complicated by some form of diabetes, with gestational diabetes being the most prevalent. Diabetes in pregnancy will increase risks to the mother and the fetus. Women with gestational diabetes have an increased risk of developing diabetes later in life. Therefore, good glycemic control is very important for pregnant women. Primary therapy for gestational diabetes is life-style changes, including body weight control, diet control, exercise and self blood glucose monitoring. When life-style changes alone cannot control blood glucose, hypoglycemic drugs must be added. Several classes of hypoglycemic drugs are available, including insulin and oral hypoglycemic drugs. Insulin is not able to cross the placenta appreciably due to its high molecular weight. Therefore, insulin has been the drug of choice for diabetes during pregnancy. However, the invasive mode of insulin administration is not convenient for the user. In the past, oral hypoglycemic agents were contraindicated during pregnancy due to concerns of teratogenecity. Recently, some studies indicate that some oral hypoglycemic agents are safer than others for pregnant women and the fetus, such as glyburide, metformin and acarbose. Furthermore, a wide range of physiological changes occur during pregnancy. These changes can significantly affect pharmacokinetics of drugs. Therefore, when establishing a drug therapy plan for gestational diabetes, pharmacokinetic changes must be taken into consideration. This article reviews blood monitoring and therapy of gestational diabetes mellitus. For drug therapy, we emphasize that pharmacokinetic consideration of insulin or oral hypoglycemic agents should be incorporated into drug therapy choices.