Hyperglycemia in pregnancy
Key points
  • Diabetes mellitus is a severe chronic disease that occurs in the production of insulin by the body, or a violation of its effective use against the background of sufficient production. There are 3 main types of diabetes mellitus: type 1 diabetes mellitus, type 2 diabetes mellitus and gestational diabetes mellitus.
  • Type 1 diabetes most often occurs in childhood but can occur at any age. At this time, it cannot be prevented. People with type 1 diabetes can only live full lives with an uninterrupted supply of insulin, sufficient awareness, support, and the availability of blood glucose testing equipment.
  • Type 2 diabetes mellitus accounts for the vast majority (about 90%) of diabetes worldwide. It is possible to effectively influence its occurrence and course through education, support and adoption of a healthy lifestyle in combination with medication, if necessary.
  • "Prediabetes" is a term that is increasingly used for people with impaired glucose tolerance and / or with impaired fasting glucose. It determines the risk of future development of type 2 diabetes and diabetes-related complications.
  • Pregnant women with gestational diabetes may have high blood sugar, blood pressure, and high birth weight in babies as a result of gestational diabetes, which increases the risk of pregnancy and childbirth complications for both mother and baby.
According to the WHO and the International Federation of Gynecology and Obstetrics (FIGO), hyperglycemia in pregnancy (HIP) can be classified as both gestational diabetes mellitus (GDM) and diabetes in pregnancy (DIP). GDM is diagnosed for the first time during pregnancy and can occur at any time during pregnancy (most likely after 24 weeks). The DIP is applied to pregnant women who have previously known diabetes or have hyperglycemia that was first diagnosed during pregnancy and meets the WHO criteria for diabetes in the non-pregnant state. DIP can also occur at any time during pregnancy, including the first trimester. It has been estimated that the majority (75–90%) of cases of HIP are GDM.

Because overt symptoms of hyperglycemia during pregnancy are rare and difficult to distinguish from normal pregnancy symptoms, OGTT is recommended for GDM screening between 24 and 28 weeks of pregnancy, but for high-risk women, screening should be done earlier. Diagnostic criteria for GDM vary and remain inconsistent, making it difficult to compare research data. There has been progress towards the diagnostic criteria promoted by the International Association of Diabetes and Pregnancy Research Groups (IADPSG)/WHO, and this has led to an overall increase in the overall prevalence of GDM. OGTT is usually performed by measuring plasma glucose concentrations during fasting and two hours after ingestion of 75 g of glucose.

In addition to women with hyperglycemia in early pregnancy, GDM occurs in women with insufficient insulin secretory capacity to overcome the reduced action of insulin (insulin resistance) due to the production of the hormone by the placenta. Risk factors for GDM include older age, overweight and obesity, previous GDM, excessive weight gain during pregnancy, family history of diabetes, polycystic ovary syndrome, habitual smoking, and a history of stillbirth or birth of a child with congenital anomalies. GDM is more common in some ethnic groups.

Overt symptoms of hyperglycemia during pregnancy are rare and difficult to distinguish from normal pregnancy symptoms.
GDM usually exists as a transient disorder during pregnancy and resolves after pregnancy ends. However, pregnant women with hyperglycemia are at greater risk of developing GDM in subsequent pregnancies. Additionally, the relative risk of developing type 2 diabetes is particularly high 3–6 years after GDM and before the age of 40. The increase in risks continues to be markedly elevated.
Given the high risk of developing type 2 diabetes in the early stages, and the fact that early onset of type 2 diabetes leads to a high risk of cardiovascular disease, any lifestyle intervention should be started within three years of pregnancy to achieve maximum benefit for diabetes prevention. Babies born to mothers with GDM also have a higher risk of obesity and developing type 2 diabetes throughout their lives.
Women with hyperglycemia detected during pregnancy are at greater risk of adverse . These include high blood pressure and a large baby for gestational age (called "macrosomia"), which can make normal delivery difficult and dangerous, and the baby is more prone to fractures and nerve damage. Detecting the time of pregnancy combined with good blood glucose control during pregnancy can reduce these risks. Women of childbearing potential who are known to have diabetes before pregnancy should receive preconception counseling, folic acid treatment at higher doses, medication review, and a systematic approach to pregnancy. , who suffer from HIP – whether it is GDM, previously undiagnosed HIP, or existing and known diabetes – require optimal prenatal care and appropriate postnatal management assistance. Women with hyperglycemia during pregnancy should be able to control their blood glucose levels through a healthy diet, moderate exercise, and blood glucose control. Interaction with healthcare professionals is important to support their self-monitoring, as well as to determine when medical (e.g., prescribing insulin or oral medications) or obstetric intervention is needed.