Diabetes mellitus is a metabolic disorder determined by the interaction of hereditary and environmental factors. Diabetes is one of the most frequent sufferings of humanity. It is difficult to establish its prevalence accurately, but in the US population it is at least 2% [National Commission on Diabetes], and yet the same part of the population has diabetes without knowing it. Judging by the statistical indicators, which for the period from 2005 to 2015 increased by 50%, the incidence of diabetes is increasing or its diagnosis is improving. The prevalence of the disease among children under the age of 17 is 0.13%, and among girls it is significantly higher than among boys. Pregnant diabetes and chemical diabetes (White class A) are likely to be complicated by 1-2% of pregnancies, and 0.1-0.2% by obvious diabetes [Beard, Oakley]. The combination of diabetes and pregnancy is a great danger to both the mother and the fetus. In the pre-insulin era, women with diabetes rarely became pregnant. More than 1/3 of sick mothers died without informing the child or after childbirth, and the survival rate of the children was also very low. At present, women with diabetes are as fertile as healthy [Farquhar]. The direct positive effect of insulin treatment on pregnancy manifested itself in terms of maternal health and survival to a greater extent than in relation to the outcome for the fetus. With the introduction of insulin, maternal mortality among patients with diabetes decreased from 25-60% in 1922 to less than 1% by 1970 [Daweke, Gutter]. Nowadays, women usually survive even with vascular complications; an exception is patients with coronary heart disease [Hare, White]. Then, attention was focused on perinatal mortality, which by 1970 was still 16.9%, despite treatment with insulin [Daweke, Gutter]. In case of insulin-dependent diabetes in the mother, the frequency of complications during the neonatal period is 50%, and among children of women with pregnant diabetes, 10-20%. Patients with diabetes and even the so-called prediabetes are characterized by an increased frequency of fetal death. Nevertheless, since insulin appeared, fetal survival has been steadily increasing, and in the last decade, many researchers have reported truly impressive results [see Gabbe]. The improvement is associated with many factors, including the improvement of insulin preparations, the use of antimicrobials and methods of antenatal assessment of the fetus. Diagnosis of diabetes mellitus During pregnancy, the threshold for renal excretion of glucose is physiologically low, so glycosuria often happens with normal blood sugar values. The presence of antenatal glycosuria serves as an indication for a glucose tolerance test, but a pathological reaction is detected only in 1/4 of the cases [Brundenell, Beard]. In late pregnancy, fasting glucose concentration is lower than normal, so women with diabetes of pregnant pregnant women on an empty stomach usually have normoglycemia. Thus, with the exception of cases of a sharp increase in glucose, its fasting level cannot be used for diagnostic purposes. The standard glucose tolerance test (STG) is the most reliable diagnostic method in the absence of clinical symptoms in the patient; indications for its use are: 1) the presence of diabetes in relatives of I or II degree, especially if the woman herself has signs of obesity; 2) history of a large child (more than 4500 g); 3) the presence in the history of polyhydramnios, unexplained perinatal death of the child or some congenital malformations; 4) glycosuria. After a minimum of a three-day training period, when a woman is on a diet that includes at least 200 g of carbohydrates, a 3-hour STG is given. In addition to the tendency to fasting hypoglycemia, in the third trimester of pregnancy glucose levels are usually normally increased 2 and 3 hours after exercise. Therefore, during pregnancy, the criteria for diagnosing diabetes should be different. O’Sullivan et al. suggested that the following blood sugar values be considered normal limits of STH (100 g glucose) during pregnancy: on an empty stomach – 900 mg / l,after 1 h — 1650, after 2 h — 1450, and after 3 h — 1250 mg / l. This is the whole blood glucose determined by the Somoggyi-Nelson method. A diagnosis of diabetes is made when two or more indicators exceed these limits. If the glucose content in the blood plasma is determined, the limits must be increased by 15%.