Blood sugar levels and pregnancy planning

Glucose is a type of sugar present in your blood. Elevated blood glucose levels are associated with pregnancy complications. Most complications are not common, but the risk of complications starts to increase as blood glucose levels rise above the healthy range. The risk of complications is highest if you have diabetes with poor control.

Complications may include:

• birth defects in your pēpi
• miscarriage
• high blood pressure complications in later pregnancy
• baby growth problems (too big or too small)
• early delivery
• pregnancy loss.

Many women do not know if they have normal blood glucose levels or not. An easy way to find out is to do a simple blood test, called HbA1c. This test can be done any time of the day.

Your healthcare provider may have done this test. It is important to aim for healthy blood glucose levels always, but especially before and during pregnancy.

The HbA1c measurement of your blood glucose provides important information about your health and your long term health risks.

What the HbA1c result means 

The HbA1c result tells us what your blood glucose levels have been like over the previous 6 to 8 weeks. It shows whether your levels are generally in a healthy range or are elevated.

If your HbA1c level is:

• close to 30mmol/mol — that is a very normal and your glucose  levels are likely to stay around that level
• close to 40mmol/mol — it is still normal but it suggests your levels may be above the usual range at times
• above 40mmol/mol — it suggests your levels are above the usual range overall (we call this pre-diabetes)
• 50mmol/mol or higher — we call this diabetes. 

HbA1c levels can go up or down a little over time, so if you are borderline (around 40), the diagnosis may not be clear until later results are looked at. For the time, apart from a healthy lifestyle, no further treatment is needed.

If you have pre-diabetes or early diabetes, you may be able to reverse it with careful lifestyle management and return yourself to more normal blood glucose levels.

Discuss with your healthcare provider the HbA1c level you should aim before pregnancy. The target is different for different women. 

If you have type 1 or type 2 diabetes, we recommend you see a specialist doctor who has expertise in helping women with diabetes plan their pregnancy.

Type 1 diabetes (internal link) 

Type 2 diabetes (internal link)

Gestational diabetes and having a healthy pregnancy if you have diabetes (internal link)