Blood Sugar and Pregnancy With Pre-Existing Diabetes

Young pregnant woman

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Blood sugar needs extra attention when a woman with pre-existing diabetes gets pregnant. Diabetes brings with it certain added pregnancy risks, so the goal is to maintain a blood sugar average that is as far below the normal level as you can without greatly increasing your risk for hypoglycemia (low blood sugar) or restricting the growth of your baby in the womb. It is important that this is done throughout the entire nine months of pregnancy.

Average blood sugar levels can be found with an A1c test. This test provides an idea of what your blood sugar average has been for the prior two to three months.

Because blood sugar has to be kept under tight control, it is useful to know if your doctor's target ranges are in whole blood or plasma measurements and what type of result your glucometer provides.

Common Blood Sugar and Pregnancy Goals

Plasma measurement results can be nine points or more above the whole blood results. This may not seem like a lot, but it can seem like a big deal when you are trying to maintain tight control. Below are common blood sugar and pregnancy goals:

  • Fasting Blood Sugar: 105 mg/dL or less
  • Before meals: 110 mg/dL or less
  • One hour after meal: 155 mg/dL or less
  • Two hours after meal: 135 mg/dL or less
  • Middle of the night (around 2:00 – 3:00 a.m.): No less than 65
  • A1c: 6.0% or less

Talk to your doctor about what blood sugar goals are best for you. Your doctor will provide goals according to your unique situation or based on other recommendations.

Expect to be asked to test your blood sugar more often. Most women are asked to test upon waking and before or after meals according to the preferences of their healthcare team and the situation. You may also be asked to check your level in the middle of the night if your fasting levels have been high.

It is recommended people with diabetes get their A1c level checked every three months. It may be checked more often during pregnancy.

Higher targets may be needed for patients who experience hypoglycemia unawareness or who are finding a strict regimen too challenging. Read tips for tight pregnancy blood sugar levels from women who have had successful pregnancies with diabetes.

Do You Want to Try to Conceive?

If you want to have a baby, speak with your endocrinologist and meet with a perinatologist for a pre-conception counseling session. Ideally, the goal is to maintain consistent normal blood sugar levels for three to six months before getting pregnant; using contraception during this period can help ensure that you don't get pregnant until you've met this goal.

1 Source
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  1. National Institute of Diabetes and Digestive and Kidney Diseases. Pregnancy if you have diabetes.

By Elizabeth Woolley
Elizabeth Woolley is a patient advocate and writer who was diagnosed with type 2 diabetes.