What is it
“gestational diabetes” means a condition of alteration of glycemic values diagnosed for the first time in pregnancy, which therefore includes both cases of diabetes actually occurring during pregnancy and forms of type 1, 2 or IGT diabetes prior to gestation, but not yet diagnosed.
In Italy the prevalence of gestational diabetes is estimated to be around 7%, although there are currently no epidemiological data on a national scale. However, the incidence of the disease is increasing, both because of an increase in metabolic diseases and obesity, and because of the immigration of women coming in particular from countries with low carbohydrate diets, due to an increased susceptibility to diabetes itself genetically determined.
In MultiMedica there is an outpatient clinic to diagnose gestational diabetes and follow the woman through all stages of pregnancy.
The diagnosis of gestational diabetes often involves difficulties due to the heterogeneity of the pathology and therefore it is often late (end of the second – beginning of the third trimester), when the metabolic alteration is now evident. In the past, attention was only paid to patients with risk factors for the development of diabetes, i.e. family history of diabetes, recurrent urinary or vulvo-vaginal infections, obesity, previous MEF, malformed fetus, previous fetal macrosomy, previous gestational diabetes, excessive weight gain in pregnancy. With this screening, aimed only at women with risk factors, however, only 50% of patients with gestational diabetes can be identified, as almost half of pregnant women who develop this disease do not have obvious risk factors. All pregnant women should therefore be screened (universal screening).
The complications of ‘diabetic’ pregnancy
Today the maternal and fetal complications of diabetes in pregnancy have decreased significantly due to advances in diagnosis and therapy and concern fetal malformations (from 6 to 9% according to different studies), miscarriages, fetal macrosomy and labor complications. These complications are linked to poor metabolic control in the various stages of pregnancy. Proof of this is the fact that if conception occurs in diabetic patients in satisfactory glycemic balance, i.e. with levels of Glycated Hemoglobin (HbA1c) kept within or close to normal (6.5-7%), and control is maintained during pregnancy, the percentage of complications is reduced to the levels found in non-diabetic pregnant women.
The woman with diabetes mellitus who wants to seek a pregnancy should first contact a Diabetes Centre, expert in the treatment of diabetes during pregnancy. There you can find advice from both the diabetologist and the gynaecologist, who can suggest the necessary tests before a pregnancy and optimize metabolic control.
The diagnostic-therapeutic path
At the first obstetrician-gynecological appointment during pregnancy, the determination of plasma glycaemia is prescribed to identify women with pre-pregnancy diabetes.
Subsequently, between the 24th and 26th week of pregnancy, each woman should perform a loading test (OGTT) with 75 g of glucose, prescribed by the gynaecologist.
At any time during pregnancy, patients with diagnostic glycemic values for gestational diabetes will be sent to the Diabetes and Pregnancy clinic, where they will be evaluated by a diabetologist.
During the first diabetological examination of the ‘Gestational Diabetes‘ path, the outpatient medical records will be compiled and the family history will be evaluated, in particular with regard to diabetes, hypertension, metabolic diseases and thyroid disorders, clinical history and eating habits, with particular attention to ethnic conditions. PA will be detected, pregravity BMI and weight gain since conception evaluated. The endocrine-metabolic evolution of pregnancy will then be evaluated, as well as the haematochemical tests performed so far. The patient will be explained the problems related to gestational diabetes and the possible impact on the evolution of pregnancy both on the fetus and on the mother also in the postgravid period (recurrence of DM and preventive lifestyles).
The patient will also be provided with a reflectometer, i.e. an instrument for measuring capillary blood glucose, instructed on how to take and maintain the glycemic diary, and at the same time a random glycemic determination will be carried out.
The initial and central point of therapy is correct nutrition. For this reason the patient will be given nutritional advice and a balanced diet plan. As an example, the recommended diet is 1,500 – 1,800 Kcal/day (24 to 30 Kcal/Kg body weight) with a content of 40-50% carbohydrates, 30% protein and 30-40% lipids. This diet becomes less caloric if the patient is overweight or obese or, instead, more caloric if the patient is underweight. As for carbohydrates, they should be split up during the day: we recommend 3 main meals (breakfast, lunch and dinner) and 2/3 snacks during the day. In addition, the patient will also be instructed on the differences between the various types of carbohydrates: simple carbohydrates (such as those contained in sweets, fruit juices, sweetened drinks and milk) are rapidly absorbed and cause a rapid rise in blood glucose; on the other hand, starches or complex carbohydrates (contained in bread, pasta, legumes) have a slower absorption, causing a lower or more delayed glycemic peak, on average 2 hours after intake. An intermediate behaviour can be observed with diets rich in rice, typical of Asian or African populations, which rapidly digested causes a greater rise in glycemic values. Water-soluble fibres, such as those contained in fruit and vegetables, slow down the absorption of carbohydrates. These instructions will be repeated during subsequent visits and their correct application will be checked.