During Pregnancy

Growing fetuses get their nutrients from mom’s blood.This includes glucose, which can fluctuate widely in women with type 1 diabetes. High maternal blood glucose levels can cause excessive growth in the developing baby and can have a lasting impact, increasing the risk of obesity and insulin resistance in children and adolescents. This is why tight blood glucose management is very important leading up to and during pregnancy. Low blood glucose levels, how- ever, do not generally cause harm to the fetus, even though they can be disrup- tive to the mother.

Insulin and Blood Glucose

Early in pregnancy, the body tends to be more responsive (sensitive) to insulin and later in pregnancy it become less sensitive (more resistant) to insulin.Your total daily insulin dose may change weekly throughout your pregnancy.

Avoiding DKAduring pregnancy is critical for fetal health. DKA can actually occur at lower glucose levels than is typical. Pay close atten- tion to glucose levels and measure ketones if your glucose levels stay above your target for more than a few hours and don’t respond to correction doses of insu- lin that you and your medical team have previously discussed. Contact your health-care team if your ketones are positive or you are concerned. If you cannot fix the situation at home, getting intravenous fluids, with or without intravenous insulin, usually quickly fixes the problem.


It’s hard not to overshoot when striving to get blood glucose down to as close to normal as possible. It is not unusual for some pregnant women with type 1 diabetes to develop hypoglycemia with a blood glucose <50 mg/dL or <2.8 mmol/L on 1 out of every 5 days, with as many as 70% experiencing severe hypoglycemia—blood glucose low that requires help from another person—at least once during preg- nancy.The risk seems to be highest during the first trimester. This may be linked to the morning sickness and nausea that is common during this stage of preg- nancy, although it also happens in women without morning sickness. A bit of good news: blood glucose lows don’t directly increase the risk of birth defects or fetal death.

Consume carbohydrates at consistent times during the first trimester and be sure you are well equipped with appropriate snacks to treat hypoglycemia: glucose tabs, glucose gels, candies, etc. It is okay to give glucagon in pregnancy. Have your partner review how to give glucagon and practice with an expired kit.

Hypoglycemia-induced dizziness, confusion, or loss of consciousness can cause car accidents, so, as usual, check your blood glucose level before getting behind the wheel. And more generally, checking blood glucose frequently is the best way to prevent and rapidly treat mild cases of hypoglycemia, and hopefully prevent severe hypoglycemia. Some women check as many as 10–20 times throughout the day and night during pregnancy. Continuous blood glucose monitoring, with its low glucose alarms, may be helpful during this more challenging time.



Up to a third of women with type 1 diabetes have Hashimoto’s disease, an auto- immune disorder of the thyroid. The thyroid plays an important role in preg- nancy, and thyroid disease can lead to pregnancy complications and birth defects.

Get checked for thyroid disease before you become pregnant. If thyroid hor- mone levels are low, they can be replaced with pregnancy-safe medications to restore healthy hormone levels.Your dose may need to be increased during the first trimester of pregnancy. Be sure your health-care provider follows your thy- roid hormone level every trimester and adjusts your medications appropriately.

Women without existing thyroid disease can develop postpartum thyroiditis: thyroid hormone levels increase after delivery and then fall to low levels. If you are feeling nervous, sweaty, or shaky, are losing weight too quickly or having palpitations (fast heartbeat) in the several months after delivery, have your thyroid hormone levels checked.


An estimated 10% of women experience depression during pregnancy. The number is higher in women with type 1 diabetes and can negatively affect health of mother and baby. Certain antidepressants can be safely taken during pregnancy. Discuss this with your healthcare provider if you are taking these medications before pregnancy or if you become depressed during pregnancy.