Treatments for gestational diabetes

Gestational diabetes mellitus (GDM) is defined by high blood sugar that develops at any time during pregnancy in a woman who does not have diabetes. It affects 3% to 6% of all pregnancies. GDM may be associated with pregnancy complications, difficult births, larger babies and higher rates of caesarean sections.

This review of eight studies (overall 1418 women) compares interventions and treatments for GDM and discusses their pros and cons. These are aimed to prevent pregnancy complications and to improve baby and mother outcomes.

Treatment for GDM consists of dietary therapy, self blood glucose monitoring, and the administration of Insulin if target blood glucose concentrations are not met with diet alone. Selected oral anti-diabetic drugs, such as Glyburide, Acarbose (Precose), or Metformin (Glucophage) may be used in some countries as well. Diabetes in pregnancy has to be followed up very closely, with monthly visits.

The present review suggests that specific interventions may be associated with better baby outcomes. For example, specific dietary advice and Insulin therapy may be associated with a lower proportion of large babies born. However it is also associated with a higher proportion of babies admitted to special care baby units. This could be because when it is known that a woman has GDM her baby will be more closely observed.

Offering specific treatment for GDM may be associated with better mother outcomes. For example, lower risk of developing pregnancy complications (as pre-eclampsia) possibly also due to close monitoring of the pregnancy. However women given specific treatments more often needed induced labor (as compared to women receiving only routine pregnancy care monitoring).

Mothers receiving oral medication had significantly lower rates of caesarean sections, and their babies were less likely to develop complications (as neonatal hypoglycemia) compared to women treated with Insulin.

Summary: this review supports the need to offer women with a diagnosis of GDM specific treatments. Oral medication seems to be associated with better baby and mother outcomes, compared to Insulin.

This review focuses on short-term outcomes while long-term, follow-up outcomes for both the mother and the baby are lacking, so are screening methods which are used to identify women with GDM.

Managing type 1 diabetes before and during pregnancy

Type 1 diabetes mellitus (T1DM) is associated with a higher risk of complications during pregnancy, both for the mother and the developing fetus. These can often be prevented with careful management. This article outlines current guidelines regarding T1DM management before and during pregnancy.

Before pregnancy

Pre-conception tests should include:

  • Measuring the HbA1c level (to assess glycemic control);
  • Blood creatinine level and the presence of protein in the urine (to assess kidney damage due to diabetes and/or hypertension - nephropathy);
  • Blood pressure measurement;
  • Thyroid function tests;
  • Eye examination (to check for retinopathy – eye damage due to diabetes).

Any abnormalities should be corrected before pregnancy. Some drugs such as ACE inhibitors (for high blood pressure) or cholesterol-lowering drugs are unsafe during pregnancy and should be discontinued or substituted. Insulin (both rapid and long-acting) is considered safe. Some women may benefit from taking low doses of Aspirin to prevent certain complications, such as pre-eclampsia (high blood pressure and protein loss in the urine).

Folic acid should be given before and during the first trimester of pregnancy to lower the risk of fetal malformations.

Glycemic control

The goal is an HbA1c level of <7.0% before pregnancy. The HbA1c level should be monitored every 2–4 weeks during pregnancy with a target level of <6% in the second and third trimester. Hypoglycemia (low blood sugar) must be avoided.

Tight glycemic control requires well-timed insulin treatment (with meals), diet and frequent monitoring of glucose levels. Women at higher risk of hypoglycemia may need continuous glucose monitoring to prevent hypoglycemia.

Pregnant women require more insulin, especially during the last trimester. However, quickly after birth, insulin requirements drop to approximately 60% of the dose needed during pregnancy. It is important to be aware of these changes and adjust insulin doses accordingly.

Treating diabetes-related complications and hypertension

High blood pressure and nephropathy increase the risk of pre-eclampsia and preterm delivery. The risk can be reduced by maintaining blood pressure <135/85 mmHg and urinary albumin (a type of protein) <300 mg per day.

Retinopathy can become worse during pregnancy. Eye examinations and proper treatment should be sought before conception.

Other hormonal disturbances, such as thyroid dysfunction, are common in women with diabetes. Treatment for low thyroid hormone levels should be started before pregnancy.

Lifestyle recommendations

Moderate physical activity (30 minutes/day) is recommended according to individual ability. This reduces the risks of pre-eclampsia and preterm delivery, and improves physical fitness and emotional wellbeing.

A diet for pregnant women with T1DM is designed to avoid single large meals and simple carbohydrates (refined sugars, candy). Insulin doses need to be adjusted according to carbohydrate intake.

Monitoring the baby

Close observation of the fetus and newborn baby are essential. Women with T1DM should have frequent ultrasounds to detect fetal malformations or excessive fetal growth. The timing and mode of delivery should be planned taking all aspects of maternal and fetal health into account.

Labor and breastfeeding

More than 50% of women with diabetes give birth by planned caesarean section. Breastfeeding provides health benefits for mother and baby and is strongly encouraged.

In summary, management of pregnant women with T1DM consists of a combination of tight glycemic control (with insulin analogues) while avoiding hypoglycemia; review and adjustment of all medications; standard pregnancy supplements (i.e. folic acid); treatment of hypertension and diabetes-related complications; and close surveillance of the embryo and newborn.

Rigor management prevents maternal and fetal complications and improves the health of the newborn baby.