An insulin pump is a computerized mechanical device about the size of a cell phone. It pumps rapid- or short-acting insulin through a length of tubing to a small catheter or needle that is inserted into the fat layer under the skin. Insulin is pumped continually at a preprogrammed basal rate, and the pump wearer programs in a bolus amount of insulin at meals and snacks based on the amount of carbohydrate in the food to be eaten. While pump therapy has been used safely and successfully in pregnant women with Type 2 and gestational diabetes, it is most commonly part of a pregnancy treatment plan for women with Type 1 diabetes.
Benefits. One advantage to using an insulin pump during pregnancy is the ability to make very small insulin dose adjustments; for example, some pumps allow adjustments in 1/40-unit increments. In addition, the basal rate of insulin infusion can be changed hourly (or even every half hour, if necessary), allowing the user to closely match insulin delivery with insulin need. These features may be particularly useful as pregnancy progresses, hormone levels change, and insulin needs change accordingly.
Risks. One of the risks of pump use is that if the infusion of insulin is disrupted for any reason, high blood glucose can occur quickly since only rapid- or short-acting insulins are used in pumps. High blood glucose is always a concern for people with diabetes, but it is especially so during pregnancy when the health of the baby is also at stake.
Low blood glucose, or hypoglycemia, is a risk with any type of insulin therapy, including pump therapy. However, it may be less of a risk with pump therapy. A study published in the journal Diabetes Care in 1996 involving 55 people with Type 1 diabetes showed that the incidence of severe hypoglycemia declined more than sixfold during the first year of insulin pump therapy as compared to previous management on multiple daily insulin injections.
Weight gain is another possible risk of insulin pump therapy. It is usually the result of at least one of the following:
- Improvement in blood glucose control. When blood glucose is high, calories are eliminated in the urine. When blood glucose is brought into the normal range, those calories are instead absorbed by the body.
- Delivery of too much insulin, leading to hypoglycemia, leading in turn to consuming carbohydrate to raise blood glucose.
- Managing high-calorie foods or large portions of food with larger or more frequent boluses of insulin.
Working closely with your diabetes management team can help you to minimize any risks associated with pump use.
Careful and constant attention to diabetes self-management tasks is essential for any pregnant woman with diabetes. Those who want to use a pump during pregnancy must also be familiar with how to operate a pump and how to troubleshoot if pump problems arise.
Healthy eating. Eating for two doesn’t mean eating twice as many calories each day. The calorie needs for pregnancy range from 2400 to 2800 calories per day for most physically active pregnant women. This translates into approximately 300 extra calories a day — the amount found in a snack of cheese and crackers or yogurt with a piece of fruit.
Because your baby’s health is so closely tied to your food intake, you should strive to pack the most nutrition power you can into the foods you eat. It’s important to eat a healthy variety of foods from all the food groups. The table “Healthy Eating During Pregnancy” is a guide to the minimum number of daily servings from each food group to meet the needs of women following a 2400-calorie-per-day diet. It is based on the Diabetes Food Pyramid. The food groups marked with an asterisk (*) are sources of carbohydrate; your intake of these foods should be individualized based on your blood glucose levels.