Gestational Diabetes: Symptoms, Values and Screening in Pregnancy
What is gestational diabetes
Gestational diabetes is a rise in blood sugar that appears or is first recognised during pregnancy, usually in the second half. It is relatively common and stems from the hormonal changes of pregnancy, which can reduce insulin's effectiveness. When found and managed in time, in most cases it does not harm mother or baby.
Symptoms: often none
In most cases gestational diabetes has no obvious symptoms. When present, signs can include increased thirst, frequent urination, fatigue or recurrent infections. Because it is often silent, screening during pregnancy is essential and is routinely recommended.
How it is diagnosed: the OGTT
Diagnosis is based on the oral glucose tolerance test (OGTT): 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 it may be brought forward to weeks 16-18. The measured values guide your gynaecologist to the diagnosis.
Risk factors
- Overweight or obesity before pregnancy
- Family history of diabetes
- Older maternal age
- A previous gestational diabetes or a high-birth-weight baby
- Polycystic ovary syndrome
Glucose in urine and pregnancy
In pregnancy, glucose can appear in the urine (glucosuria) partly due to a natural lowering of the renal threshold — so it does not always mean gestational diabetes. That is why a positive urine screening result in pregnancy should always be interpreted by your gynaecologist, who will decide whether to proceed with an OGTT.
Why managing it matters
Unrecognised gestational diabetes can raise the risk of some complications, such as high birth weight. With the right monitoring, appropriate diet, physical activity and — when needed — treatment, blood sugar is kept under control and pregnancy proceeds normally. In most cases gestational diabetes resolves after delivery, although it raises the future risk of type 2 diabetes: one more reason to keep up with checks.
Frequently asked questions
Does gestational diabetes go away after birth? In most cases yes, but a check-up after pregnancy and over time is recommended.
Can I prevent it? Not always, but a healthy lifestyle before and during pregnancy can lower the risk.
The role of screening with Rima GlucoLens
Rima GlucoLens is a non-invasive screening tool that can offer an extra signal between check-ups. It does not replace the OGTT or your doctor's assessment: in pregnancy, a positive result means "talk to your gynaecologist," not a diagnosis.
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