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.

Avoid the Risks
"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."

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"Diabetes doesn't usually interfere with fertility unless the disease is out of control or in very poor control," 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, mother of a 15-month-old son and a child due in early April.

Take Control
To achieve blood-sugar control prior to conception, Meloni recommends that women:

• Reach their near-ideal body weight.
• Follow a diet that provides good sugar control.
• Avoid hyper- and hypoglycemia. "This requires multiple injections of regular or lispro insulin per day before meals," he says. "At bedtime and/or in the morning, intermediate-acting insulin is used to smooth out the 'bumps' in blood sugar. Adding snacks to the diet and reducing meal size is often necessary."

"Plan on testing blood sugar at least 5 to 6 times a day," says Dawn Prindall of Orr's Island, Maine, mother of sons ages 11 and 6. "And get regular Heboglobin A1C tests before you get pregnant to give you an indication of how you're doing with control."

Two recent developments that have improved blood-sugar control for all diabetics, pregnant women in particular, are carbohydrate counting and Humalog, a rapidly absorbed mealtime insulin that mimics the body's own insulin activity after meals.

"Carb counting takes the guess work out of blood-sugar management, Prindall says. "There is a formula for determining insulin doses based on what you actually eat. You adjust the dose to meet your personal insulin requirements," all with adequate medical supervision, she adds.

"Carb counting lets me eat more how I want to," says Bleackley. "If I'm not feeling particularly well one day (i.e. morning sickness), I can reduce my insulin a little and eat less. In addition, carb counting makes it a little easier to adjust to increased insulin requirements as pregnancy goes on."

Amanda Clark, whose pre-existing diabetes wasn't diagnosed until 12 weeks into her first pregnancy, is now on an insulin pump for her second. The device releases insulin on-demand as her body needs it, and allows her to maintain her usual eating habits and keep her blood sugar at consistent levels, even with morning sickness.

Managing diabetes before and during pregnancy is more of a lifestyle than a chore, Bleackley says. "I get the meals on time, keep some healthy food in the fridge, try to eat normally, but a little lower in fat than most. I walk that mile to the store and carry groceries (I push them along with the stroller) instead of driving. Use the stairs instead of the elevator. Go to the pool when you have time; take a walk in the park."

A Team Approach to Healthy Pregnancy
The American Diabetes Association recommends that diabetic women, when possible, assemble a support team prior to conception. That team should include:

• An endocrinologist or physician specializing in diabetes and skilled in treating pregnant women.
• A diabetes nurse educator.
• A registered dietitian.
• An ophthalmologist.
• An obstetrician who handles high-risk pregnancies and has cared for other pregnant women with diabetes.

"It is important to remember that the mother is more than 50 percent of the 'team' in getting all this to work," says Meloni.

"I see the OB/GYNs every two weeks, the endocrinologist every four to six weeks, and maternal fetal health specialist for level II ultrasounds every four weeks," says Clark, whose second child is due in late December.

Diet demands and insulin requirements will slowly change after the third month as the pregnancy progresses, Meloni says. Both Type 1 and Type 2 diabetics will have to monitor their weight, snacks and diet composition. Insulin-dependent Type 1 diabetics may need to increase their dosage, while Type 2 diabetics controlled by diet and/or oral medication, and even those with gestational diabetes, may have to add insulin in the final trimester.

With all the attention a diabetic woman must pay to planning for pregnancy and following guidelines within it, a spouse can be an important member of the team, too. "He helped me test my blood sugar when I was tired, helped me through blood-sugar lows, encouraged me, and went to nearly every doctor's appointment to help us understand the best paths to take," says Prindall of her husband. "I couldn't have done it without him."

Want to see more?

• Healthy Eating During Preconception
• What You Should Know Before You Conceive
• Early Pregnancy: What You Should Know