Gestational diabetes mellitus includes pregestational diabetes mellitus (PGDM) and gestational diabetes mellitus (GDM), which may have been diagnosed before pregnancy or first diagnosed during pregnancy. With the increasing prevalence of diabetes mellitus and the widespread emphasis on screening and diagnosis, the number of patients with gestational diabetes mellitus is increasing.
In 2007, the Obstetrics and Gynecology Section of the Chinese Medical Association and the Collaborative Group on Combined Diabetes in Pregnancy of the Perinatal Medicine Branch of the Chinese Medical Association formulated the Draft Recommended Guidelines for Clinical Diagnosis and Treatment of Combined Diabetes in Pregnancy (Draft Guidelines), which has played an important role in guiding clinical management.
The Obstetrics and Gynecology Group of the Obstetrics and Gynecology Branch of the Chinese Medical Association and the Collaborative Group on Gestational Combined Diabetes Mellitus of the Perinatal Medicine Branch of the Chinese Medical Association have revised the draft guidelines and formulated the Guidelines for the Diagnosis and Treatment of Gestational Combined Diabetes Mellitus (referred to as the Guidelines).
The main references are the current diagnostic criteria for GDM in China, the International Diabetes in Pregnancy Study Group (IADPSG), the International Diabetes Federation, and the British, Australian and Canadian indications.
The guidelines are based on the current diagnostic criteria for GDM in China, the International Diabetes Mellitus Study Group (IADPSG), the International Diabetes Federation (IDF), and the guidelines developed by the UK, Australia and Canada. The evidence classification recommended in this guideline is shown in Table 1.
Diagnosis
For many years, there has been controversy regarding the methods and criteria for the diagnosis of GDM. For this reason, a global multicenter prospective study, the Hyperglycemia and Adverse Pregnancy Outcomes (HAPO) study, was conducted in 2001 with the support of the National Institutes of Health (NIH).
Based on the results of this study, the IADPSG proposed new criteria for the diagnosis of GDM in 2010, the American Diabetes Association (ADA) updated the diagnostic criteria for GDM in 2011, and the WHO established diagnostic criteria for hyperglycemia in pregnancy in 2013.
Meanwhile, studies have shown that strict management of mild hyperglycemia in pregnancy significantly improves maternal and child outcomes (Level A evidence). Therefore, this guideline recommends the adoption of the new internationally and nationally recommended diagnostic criteria for GDM.
I.
The diagnosis of PGDM can be confirmed if any one of the following 2 items is met.
1. Patients who have been diagnosed with diabetes mellitus before pregnancy.
2. Pregnant women who have not undergone blood glucose examination before pregnancy, especially those with high risk factors for diabetes, need to clarify the presence of diabetes during the first prenatal checkup, and should be diagnosed as having elevated blood glucose during pregnancy up to any of the following criteria
Fasting plasma glucose (FPG) ≥ 7.0 mmol/L (126 mg/dl).
Oral glucose tolerance test (OGTT), after taking sugar
Blood glucose ≥ 11.1mmol/L (200mg/dl).
With typical symptoms of hyperglycemia or hyperglycemic crisis, and random blood glucose ≥11.1mmol/L (200mg/dl).
Glycohemoglobin (HbAlc) ≥ 6.5% [standardized using the National Glycohemoglobin Standardization Program (NGSP)/Diabetes Control and Complications Test (DCCT), but HbAlc is not recommended for routine screening for diabetes during pregnancy.
Risk factors include obesity (especially severe obesity), a first-degree relative with type 2 diabetes mellitus (T2DM), a history of diabetes mellitus or delivery of a large child, and multiple births.
The risk factors include obesity (especially obesity), first-degree relative with type 2 diabetes mellitus (T2DM), history of delivery of a large child, polycystic ovary syndrome, and recurrent positive fasting urine glucose in early pregnancy.
II.
It refers to the abnormal glucose metabolism occurring during pregnancy, which should be diagnosed as PGDM instead of GDM when it is first detected during pregnancy and the elevated glucose has reached the criteria of diabetes mellitus.The diagnosis methods and criteria of GDM are as follows.
1. It is recommended that medical institutions perform OGTT for all pregnant women who have not been diagnosed with PGDM or GDM at 24 to 28 weeks of gestation and at the first visit after 28 weeks.
Methods: Fasting for at least 8 h before the OGTT, eating a normal diet for 3 days before the test, i.e., at least 150 g of carbohydrate per day, sitting still and abstaining from smoking during the examination.
During the examination, 300 ml of liquid containing 75 g of glucose was taken orally within 5 min, and venous blood was drawn from the pregnant women before and 1 and 2 h after taking the glucose, respectively.
The glucose oxidase method was used to measure the blood glucose level.
The diagnostic criteria of glucose oxidase method: before and 1 and 2 h after taking sugar, the three blood glucose values should be lower than
2, 10.0, 8.5 mmol/L (92, 180, 153 mg/dl). GDM is diagnosed when any of the blood glucose values reaches or exceeds the above criteria.
FPG ≥5.1 mmol/L can be directly diagnosed as GDM and no line is necessary; FPG <4.4 mmol/L (80 mg/dl) is very unlikely to occur as GDM, and OGTT can be temporarily excluded. If FPG ≥4.4mmol/L and <5.1mmol/L, OGTT should be performed as soon as possible.
4, pregnant women with high risk factors for GDM, the first OGTT result is normal, if necessary, OGTT can be repeated in late pregnancy.
5.The FPG level gradually decreases with the increase of gestational weeks in early and middle pregnancy, especially in early pregnancy, therefore, the FPG level in early pregnancy cannot be used as a basis for the diagnosis of GDM.
If the first visit is after 28 weeks of gestation, it is recommended that OGTT or FPG be performed at the first visit or as soon as possible after the first visit for those who have not been examined regularly.
Monitoring during pregnancy
I. Blood glucose monitoring for pregnant women
1. Blood glucose monitoring methods.
(Self-Monitoring of Blood Glucose, SMBG): Self-measurement of capillary whole blood glucose level by micro glucose meter. Newly diagnosed hyperglycemic pregnant women, those with poor or unstable blood glucose control and those who are treated with insulin during pregnancy should monitor blood glucose daily, including blood glucose 30 min before three meals, 2 h after three meals and at night.
For those with stable blood glucose control, blood glucose profile test should be performed at least once a week, and insulin dosage should be adjusted in a timely manner according to the blood glucose monitoring results; for pregnant women with GDM who do not need insulin therapy, it is recommended to monitor blood glucose at least once a week during the follow-up consultation.
For pregnant women with GDM who do not need insulin therapy, it is recommended to monitor blood glucose at least once a week, including fasting blood glucose (FBG) and 2h after three meals, four times a day.
Continuous glucose monitoring system (CGMS): It can be used for patients with unsatisfactory blood glucose control or those with obvious abnormal blood glucose and need to add blood glucose monitoring.
The CGMS can be used for pregnant women with GDM whose blood glucose control is not satisfactory or whose blood glucose is significantly abnormal and requires additional insulin. Most pregnant women with GDM do not need CGMS, and CGMS is not recommended as a means of routine clinical monitoring of blood glucose in pregnant women with diabetes.
. The goal of glucose control during pregnancy: GDM patients’ glucose should be controlled to ≤5.3, 6 and 120mg/d1 before and 2h after meal respectively, and in special cases, the glucose ≤7.8mmol/L (140mg/dL) after 1h after meal can be measured; nocturnal glucose; HbAlc should be <5.5% during pregnancy.
The patient’s blood glucose control during pregnancy should achieve the following goals: early pregnancy blood glucose control should not be too strict to prevent hypoglycemia; preprandial and nocturnal blood glucose and FPG during pregnancy should be controlled at 5.6mmol/L (60-99mg/dl), postprandial peak blood glucose 5.6-7.1mmol/L (100-129mg/dl), HbAlc＜6.0%.
Regardless of GDM or PGDM, if glucose during pregnancy does not reach the above standards after diet and exercise management, insulin or oral hypoglycemic drugs should be added in time to further control blood glucose.
2.Measurement of HbAlc level: HbAlc reflects the average blood glucose level in the 2-3 months before blood sampling, and can be a good indicator to assess the long-term control of diabetes, mostly used for
It is mostly used for the initial assessment. For pregnant women with diabetes mellitus treated with insulin, it is recommended to test once every 2 months.
Urine ketone body monitoring: Urine ketone body can help to detect the lack of carbohydrate or energy intake of pregnant women in time, and is also a sensitive indicator of early diabetic ketoacidosis (DKA), and pregnant women should monitor urine ketone body in time when they have unexplained nausea, vomiting, weakness and other discomforts or when their blood glucose control is not satisfactory.
4. Monitoring of urine glucose: Since a positive urine glucose during pregnancy does not really reflect the blood glucose level of the pregnant woman, it is not recommended to use urine glucose as a routine monitoring means during pregnancy.
Second, the monitoring of maternal complications
1.Monitoring of hypertensive disorders in pregnancy: the blood pressure and urine protein of pregnant women should be monitored during each pregnancy checkup, and once the complication of preeclampsia is found, it should be treated according to the principles of preeclampsia.
2, monitoring of excessive amniotic fluid and its complications: pay attention to the uterine height curve and uterine tension of pregnant women, if the uterine height increases too fast or the uterine tension increases, promptly perform B ultrasound examination to understand the amount of amniotic fluid.
3, monitoring of DKA symptoms: if there is unexplained nausea, vomiting, weakness, headache or even coma during pregnancy, pay attention to checking blood glucose and urine ketone levels, and if necessary, perform blood gas analysis to clarify the diagnosis.
4.Monitoring of infection: pay attention to whether pregnant women have increased leucorrhea, vulvar itching, urinary urgency, urinary frequency, urinary pain and other manifestations, and perform regular routine urine tests.
5.Monitoring of thyroid function: perform thyroid function test when necessary to understand the thyroid function of pregnant women.
6.Monitoring of other complications: in cases of diabetes mellitus with microangiopathy combined with pregnancy, renal function, fundus examination and lipid testing should be performed in the early, middle and late stages of pregnancy respectively.
Fetal monitoring
1. Monitoring of fetal development: prenatal screening of fetus by ultrasound in the middle of pregnancy. For pregnant women whose blood sugar is not controlled in the early stage of pregnancy, it is especially important to apply ultrasound to check the development of fetal central nervous system and heart, and fetal echocardiography is recommended if available.
2. Monitoring of fetal growth rate: Ultrasound examination should be performed every 4-6 weeks during late pregnancy to monitor fetal development, with special attention to monitoring changes in fetal abdominal circumference and amniotic fluid volume.
Evaluation of fetal development in utero: pregnant women in late pregnancy should pay attention to monitoring fetal movement. If insulin or oral hypoglycemic drugs are needed, NST (stress-free test) should be performed once a week from 32 weeks of pregnancy. The fetal growth restriction should be monitored closely especially when it is suspected.
4. Promote fetal lung maturation: If the glycemic control is unsatisfactory during pregnancy and early termination of pregnancy is required, the fetal lung maturation should be monitored before the planned termination of pregnancy.
5.Promote fetal lung maturation. If possible, amniocentesis should be performed to extract amniotic fluid to understand the maturity of fetal lung and intra-amniotic injection of dexamethasone.
6.Or take intra-muscular injection, but the latter should be used to monitor the change of maternal blood sugar.
Consultation and treatment
I. Before pregnancy
(I) General advice
Pre-pregnancy counseling is recommended for all women with diabetes, impaired glucose tolerance (IGT) or impaired fasting glucose (IFG; i.e., prediabetes) who are planning a pregnancy.
Since the likelihood of GDM in a second pregnancy is 30% to 50% in those with a history of GDM, it is best for those planning a pregnancy more than 1 year after delivery to have OGTT before planning a pregnancy, or at least early in the pregnancy. If glucose is normal, OGTT should still be performed at 24 to 28 weeks of gestation (level B evidence).
Patients with diabetes should be aware of the possible effects of pregnancy on their condition. In addition to hyperglycemia, early pregnancy reactions (e.g., abnormal feeding due to morning sickness) may increase the risk of hypoglycemia. Patients with diabetes need to be evaluated for complications such as diabetic retinopathy (DR), diabetic nephropathy (DN), neuropathy, and cardiovascular disease before planning pregnancy. If chronic complications of diabetes are present, the symptoms may worsen during pregnancy and need to be re-evaluated during the pregnancy examination.
(II) Evaluation of diabetic complications
1. DR: Diabetic patients with planned or definite pregnancy should undergo an eye examination and evaluation of risk factors that may aggravate or contribute to the progression of DR. When there are indications, such as proliferative DR, taking laser treatment can reduce the
The risk of aggravation of the lesion.
Fundus changes should be closely followed during pregnancy until 1 year postpartum (Level B evidence). Good glycemic control before and during pregnancy may prevent progression of the disease.
2. DN: Pregnancy can cause temporary renal hypoplasia in patients with mild DN. Renal insufficiency has adverse effects on fetal development; patients with more severe renal insufficiency
In patients with more severe renal insufficiency (serum creatinine >265umol/l) or creatinine clearance <50ml/(min?1.73m2), pregnancy can cause permanent damage to renal function in some patients.
Therefore, pregnancy is not recommended for this group of patients.DN Those with normal renal function will have less impact on renal function if glucose control is ideal during pregnancy.
3. other complications of diabetes mellitus: diabetic neurological related lesions including gastroparesis, urinary retention and postural hypotension can further increase the difficulty of diabetes mellitus management during pregnancy.
If underlying cardiovascular disease is not identified and managed, pregnancy can increase the patient’s risk of death, and evidence of cardiovascular disease should be carefully examined and managed prior to pregnancy. Women with diabetes who are planning to become pregnant should have cardiac function at a level that can tolerate exercise testing.
(C) Rational use of pre-pregnancy medications
Women should discontinue medications contraindicated in pregnancy, such as angiotensin-converting enzyme inhibitors (ACEI) and angiotensin II receptor antagonists, prior to pregnancy.
If ACEI is used to treat DN before pregnancy, it should be discontinued as soon as pregnancy is detected. Patients should be informed during prenatal counseling that proteinuria may be significantly worse after discontinuation of ACEI before or during pregnancy.
1. In pregnant women with diabetes combined with chronic hypertension, the goal of blood pressure control during pregnancy is 110-129 mmHg (1 mmHg = 0.133 kPa) for systolic and diastolic blood pressure. Available evidence suggests that the application of labetalol and calcium channel blockers in early pregnancy do not significantly increase the risk of fetal teratogenicity and can be applied before as well as during pregnancy.
However, ACEI and angiotensin II receptor antagonists are contraindicated in mid- and late pregnancy (Level E).
2. Pre-pregnancy and early pregnancy in diabetic patients should be supplemented with multivitamins containing folic acid.
3. Patients with T2DM on metformin need to consider the possible benefits or adverse effects of the drug. If the patient is willing, the application can be continued under the guidance of the physician.
(IV) Pre-pregnancy glycemic control
The risk of miscarriage and fetal malformation in early pregnancy is significantly increased in pregnant women with diabetes mellitus who have unsatisfactory blood glucose control; ideal blood glucose control before and after pregnancy can significantly reduce the above risk, but there is no definite blood glucose threshold standard to reduce the above risk. Diabetic patients planning pregnancy should try to control blood glucose to
＜HbAlc can be less than 7% if insulin is used (level B evidence).
II. Pregnancy
(i) Medical nutrition therapy
The aim of medical nutrition therapy is to keep the blood glucose of pregnant women with diabetes mellitus within the normal range, to ensure a reasonable nutritional intake of pregnant women and fetuses, and to reduce the occurrence of maternal and fetal complications.
Two randomized controlled trials since 2005 provide strong evidence for nutritional treatment and management.
Once GDM is diagnosed, patients should be given immediate medical nutrition therapy and exercise instruction, as well as education on how to monitor blood glucose. After medical nutrition therapy and exercise instruction, FPG and postprandial
If the FPG and postprandial glucose are still abnormal after medical nutrition treatment and exercise instruction, insulin is recommended to be applied in time.
(2) Recommended nutritional intake
1. Total daily energy intake: it should be determined according to the body mass before pregnancy and the growth rate of body mass during pregnancy. See table
See Table . Although it is necessary to control the total daily energy intake of pregnant women with diabetes, excessive energy restriction should be avoided, and it should be ensured that it is not less than 1500 kcal/d (1kcal=4.184kJ) in early pregnancy and not less than carbohydrate intake in late pregnancy may lead to the occurrence of ketosis, which will have adverse effects on both the pregnant woman and the fetus.
2, carbohydrates: recommended dietary carbohydrate intake of 50% to 60% of the total energy is appropriate, daily carbohydrate not less than
It is more appropriate to maintain normal blood sugar during pregnancy. Refined sugars such as sucrose should be avoided as much as possible, and low glycemic index foods can be preferred when choosing equal carbohydrate foods.
(Whether using carbohydrate counting, food exchange portion method or empirical estimation, monitoring carbohydrate intake is the key strategy level evidence for achieving glycemic control). When only total carbohydrate is considered, glycemic index and glycemic load may be more helpful for glycemic control (Level B evidence).
3. Protein: The recommended dietary protein intake is 15% to 20% of the total energy to meet the needs of physiological regulation during pregnancy and fetal growth and development.
Fat: The recommended dietary fat intake accounts for 20% to 30% of the total energy is appropriate. However, foods with high saturated fatty acid content, such as animal fats, red meat, coconut milk, full-fat dairy products, etc., should be appropriately restricted, and the intake of saturated fatty acids in pregnant women with diabetes should not exceed 7% of the total energy intake (evidence); while monounsaturated fatty acids, such as olive oil and camellia oil, should account for more than 1/3 of the energy supply from fat.
Reducing the intake of trans fatty acids can lower LDL cholesterol and increase HDL cholesterol level (Level A evidence), so pregnant women with diabetes should reduce the intake of trans fatty acids (Level B evidence).
4. Dietary fiber: It is a polysaccharide that does not produce energy. Pectin in fruits, algae gum in kelp and nori, guanidine gum in some beans and konjac flour have the function of controlling the rise of blood sugar after meals, improving glucose tolerance and lowering blood cholesterol.
The recommended daily intake is 25 to 30 g. The diet can be rich in dietary fiber such as oatmeal, buckwheat noodles and other coarse grains, as well as fresh vegetables, fruits, algae food, etc.
5, vitamins and minerals: during pregnancy, the need for iron, folic acid and vitamin D increased by one, calcium, phosphorus, thiamine, vitamin B6 increased by 20% to 50%, zinc, riboflavin increased by 20% to 25%, vitamin A, B12, C, selenium, potassium, biotin, niacin and total daily energy needs increased by about 18%.
Therefore, it is recommended that foods rich in vitamin B6, calcium, potassium, iron, zinc and copper, such as lean meat, poultry, fish, shrimp, dairy products, fresh fruits and vegetables, be increased systematically during pregnancy.
6. Use of non-nutritive sweeteners: The ADA recommends that only non-nutritive sweeteners approved by the U.S. Food and Drug Administration (FDA) be used.
The ADA recommends that only non-nutritive sweeteners approved by the U.S. Food and Drug Administration (FDA) should be used by pregnant women, and moderately recommended.
Currently, there are very limited studies (Level E evidence). The five FDA-approved non-nutritive sweeteners are potassium acesulfamate, aspartame, neotame, saccharin, and sucralose.
(3) Reasonable arrangement of meals
Small and frequent meals and regular meals are very important for blood sugar control. The energy of breakfast, lunch and dinner should be controlled at 10%-15%, 30% and 30% of the total daily energy intake, and the energy of each additional meal can account for
percent to 10 percent, which helps prevent excessive hunger before meals.
The process of medical nutrition therapy should be closely coordinated with insulin application to prevent the occurrence of hypoglycemia. Meal planning must be individualized, and reasonable meal arrangements and corresponding nutrition education should be made according to cultural background, lifestyle, economic conditions and education level.
(D) Exercise therapy for GDM
1, the role of exercise therapy: exercise therapy can reduce the basal insulin resistance during pregnancy, is one of the comprehensive treatment measures of GDM, after 30min of each meal, moderate intensity exercise has no adverse effects on the mother and child.
2, the method of exercise therapy: choose a low to moderate intensity aerobic exercise (also known as endurance exercise), mainly refers to the body’s large muscle groups to participate in continuous exercise. Walking is a simple aerobic exercise commonly used.
3, the exercise time: can start from 10min, gradually extended to 30min, which can be interspersed with the necessary intervals, it is recommended that the exercise after meals.
4, the frequency of exercise: the appropriate frequency is 3 to 4 times / week.
5, exercise treatment precautions.
Electrocardiogram before exercise to exclude cardiac disorders, and to confirm the presence of macrovascular and microvascular complications.
Contraindications to exercise therapy.
Type 1 diabetes combined with pregnancy, heart disease, retinopathy, multiple pregnancies, cervical insufficiency, preterm labor or miscarriage, fetal growth restriction, placenta praevia, hypertensive disorders in pregnancy, etc.
Prevent hypoglycemic reaction and delayed hypoglycemia: eat for 30min before exercising, control the duration of each exercise to 30~40min, and rest after exercise. Stop exercising if the blood sugar level is <3.3mmol/L or >13.9mmol/L. Carry cookies or candies with you when you exercise, so that you can eat them in time when there are signs of hypoglycemia.
Seek medical attention when the following conditions occur during exercise: abdominal pain, vaginal bleeding or running water, breath-holding, dizziness, severe headache, chest pain, muscle weakness, etc.
Avoid exercising early in the morning on an empty stomach before insulin injection.
(E) Insulin therapy
1. Commonly used insulin preparations and their characteristics.
Ultra-short-acting human insulin analogues: Menthol insulin has been approved by the State Food and Drug Administration (State Food and Drug Administration, China) for use in pregnancy.
It is approved for use in pregnancy. It is characterized by rapid onset of action and short duration of drug maintenance. It has the strongest or best effect of lowering postprandial blood glucose and is less prone to hypoglycemia, and is used to control postprandial blood glucose levels.
Short-acting insulin: It is characterized by rapid onset of action and easy dose adjustment, and can be used subcutaneously, intramuscularly and intravenously. After intravenous injection of insulin, it can make blood glucose drop rapidly, with a half-life of 5-6 min, so it can be used for rescue.
Medium-acting insulin: It is a suspension containing fisetin, short-acting insulin and zinc ion, which can only be injected subcutaneously but not intravenously.
After injection, insulin must be separated from fisetin by the decomposition of protease in tissues, and then insulin is released to exert biological effects. It is characterized by slow onset and long duration of effect, and its strength of lowering blood sugar is weaker than that of short-acting insulin.
Long-acting insulin analogues: Dietary insulin has also been approved by SFDA for use in pregnancy to control nocturnal blood glucose and preprandial blood glucose. The various insulin preparations commonly used in pregnancy and their action characteristics are shown in Table
.
2. Timing of insulin application: After diabetic pregnant women are treated with diet for 3 to 5 d, the 24-h terminal blood glucose (blood glucose profile test) is measured, including nighttime blood glucose, 30 min before and after three meals.
Blood glucose and urinary ketone bodies.
If fasting or pre-meal glucose was ≥5.3mmol/L (95mg/dl), or post-meal
blood glucose≥6.7mmol/L (120mg/d1), or starvation ketosis after diet adjustment, and blood glucose exceeds the pregnancy standard after increasing caloric intake, insulin treatment should be added promptly.
3. Insulin treatment regimen: The insulin treatment regimen that best meets the physiological requirements is: basal insulin combined with pre-meal ultra-short-acting or short-acting insulin. The replacement effect of basal insulin can last for 24h, while pre-meal insulin has fast onset and short duration, which is conducive to the control of postprandial blood glucose. Individualized insulin treatment plan should be selected according to the results of blood glucose monitoring.
Basal insulin therapy: choose medium-acting insulin for subcutaneous injection before bedtime, which is suitable for pregnant women with high fasting glucose; for those whose fasting glucose has reached the standard after medium-acting insulin injection before bedtime but whose glucose is not well controlled before dinner, choose to inject before breakfast and before bedtime, or inject long-acting insulin before bedtime.
Pre-meal ultra-short-acting or short-acting insulin therapy: pregnant women with elevated postprandial glucose should have ultra-short-acting or short-acting human insulin injected at mealtime or 30min before meal.
Insulin combination therapy: The combination of medium-acting insulin and ultra-short-acting or short-acting insulin is the most common method currently used, i.e. short-acting insulin is injected before three meals and medium-acting insulin is injected before bedtime. Due to the significant increase in postprandial glucose during pregnancy, the routine application of premixed insulin is generally not recommended.
4. Precautions for insulin application during pregnancy.
The initial use of insulin should start with a small dose, 0.3 to O.8 U/(kg?d). The total amount of insulin planned for daily application should be allocated for use before three meals, and the principle of allocation is the most before breakfast, the least before Chinese food, and the middle amount before dinner. Observe after each adjustment.
To judge the efficacy, it is appropriate to increase or decrease 2-4u or no more than 20% of the daily insulin dosage each time until the goal of blood glucose control is achieved.
Treatment of early morning or fasting hyperglycemia during insulin therapy: Insufficient insulin action at night, dawn phenomenon and Somogyi phenomenon can all lead to hyperglycemia. The former
In the former case, the dosage of medium-acting insulin must be increased at bedtime, while the dosage of medium-acting insulin at bedtime should be reduced in case of Somogyi phenomenon.
Changes in the body’s insulin requirement during pregnancy: the insulin requirement increases to different degrees in the middle and late stages of pregnancy; the insulin requirement peaks from 32 to 36 weeks of pregnancy and decreases slightly after the first week of pregnancy.
The amount of insulin should be adjusted continuously according to the results of individual blood glucose monitoring.
(VI) Application of oral hypoglycemic drugs in pregnant women with GDM Most pregnant women with GDM can achieve the blood glucose standard through lifestyle interventions, and those who cannot achieve the standard should first be recommended to apply insulin.
Most pregnant women with GDM can achieve the blood glucose standard through lifestyle interventions, but those who cannot should first be recommended to apply insulin to control blood glucose.
At present, the safety and efficacy of oral hypoglycemic drugs metformin and glibenclamide in pregnant women with GDM have been continuously confirmed. However, there is a lack of relevant studies in China, and these
These oral hypoglycemic agents are not included in the registration indications for the treatment of diabetes mellitus during pregnancy in China.
However, considering the potential risk of applying the above oral hypoglycemic agents in pregnant women with high insulin dosage or refusal to apply insulin is much less than the risk of uncontrolled gestational hyperglycemia itself to the fetus. Therefore, on the basis of informed consent, some
pregnant women can be used with caution. The classification of oral hypoglycemic agents and their characteristics are shown in Table 4.
Glibenclamide: It is the most widely used oral hypoglycemic drug for the treatment of GDM, and the target organ is the pancreas. 99% of it exists in protein-bound form and rarely passes the placental barrier.
Clinical studies have shown that glibenclamide is more effective in mid- and late-pregnancy
The efficacy of glibenclamide in pregnant women is the same as that of insulin treatment, but the former is easy to use and cheaper. However, the risk of preeclampsia and neonatal jaundice requiring phototherapy increases after the use of the drug, and a small number of pregnant women have nausea, headache and hypoglycemic reactions.
2, metformin: can increase the sensitivity of insulin, the current data show that the application of early pregnancy is not teratogenic to the fetus, and has an important role in the maintenance of early pregnancy in the treatment of polycystic ovary syndrome. Since the drug can cross the placental barrier, the long-term safety of the drug for the fetus in the middle and late pregnancy has yet to be confirmed.
Timing and mode of delivery
(I) Timing of delivery
1.Pregnant women with GDM who do not need insulin therapy and whose blood glucose control is up to standard can wait for the expected date of delivery under close monitoring if there are no maternal and fetal complications, and those who are not in labor by the expected date of delivery can be induced to terminate the pregnancy.
2, PGDM and insulin-treated GDM pregnant women, if the blood sugar control is good and no maternal and child complications, under close monitoring, the pregnancy can be terminated after the first week of pregnancy.
If the glucose control is unsatisfactory or maternal and child complications occur, the pregnancy should be admitted to the hospital for observation in time, and the timing of termination should be decided according to the condition.
3. Those with diabetes mellitus with microangiopathy or previous history of adverse delivery should be closely monitored and the timing of termination of pregnancy should be individualized.
(ii) Mode of delivery
Diabetes itself is not an indication for cesarean delivery. If you decide to deliver vaginally, you should make a delivery plan and closely monitor the maternal blood glucose, contractions and fetal heart rate changes during labor to avoid prolonged labor. Surgical indications for elective cesarean delivery are diabetes mellitus with severe microangiopathy or other obstetric indications.
The indications for cesarean delivery should be relaxed in cases of poorly controlled glucose during pregnancy, large fetus (especially if the fetal mass is estimated to be ≥ 4250 g) or previous history of stillbirth or stillbirth.
Management of special cases
I. Principles of insulin use during labor and perioperative period
1. Principles of use: All subcutaneous insulin injections should be stopped before and after surgery, during labor and delivery, and during the postpartum period when the diet is not normal, and intravenous insulin drips should be used instead to avoid hyperglycemia or hypoglycemia.
Adequate glucose should be provided to the mother to meet the basal metabolic needs and energy expenditure under stress; insulin should be supplied to prevent
the occurrence of hyperglycemia, control hyperglycemia and facilitate the utilization of glucose; maintain proper blood volume and electrolyte metabolic balance.
2. Examination during labor or before surgery: blood glucose and urinary ketone body levels must be detected. Electrolytes, blood gas analysis and liver and kidney function must also be checked for elective surgery.
3. Insulin use: monitor blood glucose every 1-2 hours and maintain small doses of insulin intravenously according to blood glucose values. When insulin is used to control blood glucose during pregnancy, when delivery is planned, before induction of labor
The medium-acting insulin should be used normally before bedtime; on the day of induction of labor, the insulin before breakfast should be stopped and 0.9% sodium chloride injection should be given intravenously.
When labor is officially approaching or the blood glucose level is <3.9 mmol/L, change the intravenous 0.9% sodium chloride injection to 5% dextrose and lactated Ringer's solution and drip at 100 to maintain the blood glucose level at 5.6 mmol/L (100 mg/d1).
If the blood glucose level was >5.6mmol/L, 5% glucose solution with short-acting insulin was used and titrated at a rate of 1-4U/h intravenously. Blood glucose levels were monitored hourly using a rapid glucose meter, which was used to adjust the rate of insulin or glucose infusion. Blood glucose can also be regulated according to the method in Table 5.
Management of combined pregnancy and DKA
1. Pregnancy combined with
Clinical manifestations and diagnosis: nausea, vomiting, weakness, thirst, excessive drinking, polyuria, a few with abdominal pain; dry skin and mucous membrane, sunken eyes, ketone odor in exhalation, consciousness impairment or coma in severe cases.
Laboratory tests showed hyperglycemia >13.9 mmol/L (250 mg/dl), positive urinary ketone bodies, blood
<7.35, carbon dioxide binding <13.8 mmol/L, blood ketone bodies >5 mmol/L, and electrolyte disturbance.
2. Causes of morbidity: diabetes mellitus missed during pregnancy, not diagnosed or treated in time; irregular insulin treatment; unreasonable dietary control; stressful conditions during labor and before and after surgery; co-infection; use of glucocorticoids, etc.
3.Treatment principle: give insulin to lower blood glucose, correct metabolic and electrolyte disorders, improve circulation, and remove causative factors.
4. Specific steps and precautions for treatment.
If the blood sugar is too high (>16.6mmol/L), insulin should be given 0.2-0.4u/kg intravenously at one time.
Insulin continuous intravenous infusion: 0.9% sodium chloride injection + insulin at the rate of insulin 0.1U/(kg?h) or 4-6U/h.
Blood glucose monitoring: Monitor blood glucose once an hour from the beginning of insulin administration, and adjust according to the blood glucose decrease, requiring an average blood glucose decrease of 3.9 or 30% of the blood glucose level before intravenous drip per hour. Those who fail to reach this standard may have insulin resistance, and the insulin dosage should be doubled.
When the blood glucose drops to 13.9mmol/L, change 0.9% sodium chloride injection to 5% glucose solution or glucose saline, and add 1U insulin for every 2.4g glucose until the blood glucose and urine ketone body are negative, and stop rehydration when the treatment can be smoothly transitioned to subcutaneous injection before meal.
Note: The principle of rehydration is fast then slow, salt first then sugar; pay attention to the balance of the amount of people. After starting intravenous insulin therapy and the patient has urine, potassium should be replenished in time to avoid severe hypokalemia.
When pH＜7.1, carbon dioxide binding force＜10mmol/L, HCO3-＜10mmol/L, alkali can be supplemented, usually with 5% NaHCO3-100ml+injection water at the rate of 200ml/h intravenously, until pH≥7.2 or carbon dioxide binding force＞15mmol/L, stop alkali supplementation.
III. Postpartum treatment
1. Postpartum insulin application: The target of postpartum glucose control and insulin application are referred to the standard of glucose control in non-pregnancy period.
During the period of fasting or failure to resume normal diet after cesarean section for women who applied insulin during pregnancy, intravenous infusion is given, and the ratio of insulin to glucose is
2. Monitor blood glucose level and urinary ketone body at the same time, and decide whether to apply and adjust insulin dosage according to the monitoring results.
For those who apply insulin during pregnancy, once normal diet is resumed, blood glucose monitoring should be performed in a timely manner. If the blood glucose level is significantly abnormal, insulin should be injected subcutaneously and the dose should be adjusted according to the blood glucose level, and the dose of insulin required is generally significantly reduced compared with that during pregnancy.
GDM women who do not need insulin treatment during pregnancy can resume normal diet after delivery, but should avoid high sugar and high fat diet.
3, postpartum review: postpartum FPG repeatedly ≥ 7.0 mmol / L, should be regarded as PGDM, recommended to refer to endocrine specialist treatment.
4, encourage breastfeeding: postpartum breastfeeding can reduce the application of maternal insulin, and the risk of diabetes in the offspring decreases.
Neonatal management: (1) Newborns are prone to hypoglycemia after birth, and close monitoring of their blood glucose changes can detect hypoglycemia in time. It is recommended that the newborn be tested for terminal blood glucose within 30 minutes after birth.
All newborns should be treated as high-risk babies, and attention should be paid to warmth and oxygenation. (3) Early feeding of sugar water and milk, and if necessary, slow intravenous infusion of 10% glucose solution. (4) Routinely check hemoglobin, potassium, calcium, magnesium and bilirubin.
Pay close attention to the occurrence of neonatal respiratory distress syndrome.
Postpartum follow-up of pregnant women
Pregnant women and their offspring are at high risk for diabetes mellitus. A meta-analysis showed that the relative risk of postpartum T2DM in patients with GDM was %CI:4.79-11.51).
A study by the Diabetes Prevention Program (DPP) in the United States showed that lifestyle changes and medication could reduce the incidence of diabetes in women with a history of diabetes.
A study by the Diabetes Prevention Program (DPP) showed that lifestyle changes and medication could reduce the incidence of diabetes in women with a history of diabetes by more than 50%.
Therefore, the existing standards for the diagnosis and treatment of GDM regulate postpartum follow-up. Follow-up at 6 to 12 weeks postpartum is recommended for all women with GDM (Level E evidence).
The significance of postpartum follow-up should be explained to the mother; she should be guided to change her lifestyle, eat properly and exercise appropriately, and breastfeeding should be encouraged.
It is recommended to measure height, body mass, body mass index, waist circumference and hip circumference, and to understand the recovery of postpartum blood glucose, and all women with GDM are recommended to have OGTT after delivery to measure fasting and post-glucose levels.
It is recommended that all women with GDM should undergo OGTT after delivery to determine fasting and post-sugar levels, and to clarify the presence and type of glucose metabolism abnormalities according to the 2014 ADA criteria, as shown in Table 6.
Lipid and insulin levels are recommended if available, with follow-up at least every 3 years (Level Evidence).
Follow-up of the offspring of diabetic patients is recommended, as well as healthy lifestyle guidance, with measurements of length, body mass, head circumference, abdominal circumference, and blood pressure and glucose if necessary.