Abstract
A 24-year-old primigravida 161 cm tall, weighing 70 kg, and having a BMI of 27.0 before pregnancy and diagnosed with gestational diabetes mellitus (GDM) in a 75 g oral glucose tolerance test (OGTT) on day 4 of gestational week 23 (23w4d) was hospitalized on 26w5d. Ritodrine hydrochloride was administered to delay premature labor and insulin therapy was initiated 3 days later. Premature labor persisted despite maximum ritodrine dosage and the subject was transferred to our hospital on 29w0d. She was administered 12 mg of betamethasone intramuscularly on 29w0d and 29w1d. Magnesium sulfate infusion at ~2 g/hr was administered until 36w1d. Ritodrine at ~200 μg/min was continued until 37w0d. Her insulin requirement increased from 70 U/day on 29w0d to 203 U/day on 35w0d. It began decreasing after ritodrine was discontinued and decreased markedly from 178 U/day to 20 U/day. She delivered a normal male baby weighing 2714 g on 38w2d and insulin treatment was discontinued. A 75 g OGTT after delivery showed a normal glucose tolerance curve. This case suggests that some GDM subjects require more insulin during tocolysis than previously reported, and emphasizes the need to carefully observe such subjects during ritodrine hydrochloride and magnesium sulfate therapy.
