Glucosuria in Pregnancy: Is It Dangerous?

Glucose in urine during pregnancy: is it common?

Finding glucose in the urine during pregnancy is relatively common and does not always indicate a problem. Pregnancy brings important physiological changes: blood flow to the kidneys increases and the renal threshold — the blood-sugar level above which glucose passes into urine — drops. As a result, glucose can appear even with entirely normal blood sugar. This is called benign gestational glucosuria.

When it does need follow-up

Glucosuria in pregnancy can, however, also be a sign of gestational diabetes, a form of diabetes that appears or is first recognised during pregnancy. Telling a benign cause apart from possible gestational diabetes is not possible with a urine test alone: that is why glucose in the urine should not be ignored, and your gynaecologist decides what to do next.

The reference test: the OGTT

To confirm or rule out gestational diabetes, the oral glucose tolerance test (OGTT) is used: a fasting blood draw, then a sugary drink, then further draws after one and two hours. It is usually done between weeks 24 and 28; in higher-risk women (overweight, family history, previous gestational diabetes) it may be brought forward to weeks 16-18. Glucosuria does not replace this test, which remains the diagnostic reference.

Why it matters not to underestimate it

Unrecognised gestational diabetes can carry risks for mother and baby, such as high birth weight or delivery complications. The good news is that, when found and managed in time with monitoring, diet and — when needed — treatment, in most cases pregnancy proceeds without complications. That is why screening and regular checks are so important.

Frequently asked questions

Is glucosuria in pregnancy dangerous? It is often benign and linked to the normal changes of pregnancy, but should always be reported to your gynaecologist, because in some cases it indicates gestational diabetes.

If I have glucosuria, do I have to do the OGTT? Your gynaecologist will decide, weighing your risk factors and the overall picture.

The role of non-invasive screening

A tool like Rima GlucoLens can offer an extra, convenient and needle-free signal between check-ups. In pregnancy, though, a positive result means "talk to your gynaecologist": it is not a diagnosis, but an invitation to follow up.

References: World Health Organization (WHO); American Diabetes Association (ADA); MSD Manuals. This article is for information only and does not replace medical advice.

Last updated: July 2026