It's All in the Planning

Diabetes and Conception

By Phyllis Ring

Many doctors once discouraged women with diabetes from having children at all, but advances in insulin use and diet management have significantly improved prospects for a healthy pregnancy and delivery.

Experts say it's all in the planning, and in a regimen that safeguards mother and baby. Both pre-existing and gestational diabetes require blood-sugar control throughout pregnancy. The difference is that gestational diabetes occurs after a woman is pregnant, when her unborn child is already well-developed. (This type of diabetes generally disappears after birth, though it can recur in the future.)

However, women with pre-existing diabetes must, for the baby's well-being, master tight control of blood sugar before conception, maintain it during early pregnancy as infant organ systems develop, and in later trimesters, so the baby won't grow too large.

"Plan on achieving excellent blood-sugar control by six months before conception," recommends Robert Meloni, M.D., fellow of the American College of Endocrinology. "It takes time to get everything together – diet, exercise, insulin – in the proper proportion for continuous, excellent control."

Most diabetic-related fetal birth defects occur before women even know they're pregnant and are due to fetal exposure to the diabetic mother's high blood sugars in the first two weeks of development, he says. "If severe defects occur, they cannot be 'fixed' by good sugar-control later."

"Diabetes doesn't usually interfere with fertility unless the disease is out of control or in very poor control," Dr. Meloni says. He cites birth defects that result from poor preconception blood-sugar control as macrosomia (baby over 9.5 pounds); immature lung development; cardiovascular or central-nervous-system malformations; and cleft palate.

Mothers with either pre-existing or gestational diabetes can tend to have larger babies when their high blood-sugar levels constantly feed their child glucose through the placenta. Babies respond with increased growth, much of it stored as fat, and eventually develop high insulin levels of their own. This can lead to another potential infant risk – severe postpartum hypoglycemia – when a baby's insulin levels remain high following birth and the mother's glucose can no longer counteract them.

For the mother, poorly controlled diabetes also increases the risk for miscarriage in the early weeks, with the rate about twice as high for women with uncontrolled diabetes. Other possible complications of diabetes itself, such as neuropathy and retinopathy, can worsen in pregnancy if there is poor sugar control. "During my first pregnancy, I was sent to an eye specialist during and after, just to make sure that there was no damage to the blood vessels," says Christine Bleackley of Aylmer, Quebec.

Want to see more?

• Healthy Eating During Preconception
• What You Should Know Before You Conceive
• Preconception Visits: Working With Your Doctor
• Talk about it!