Maternal Hyperglycaemia During Pregnancy Flashcards
Why does Diagnosing Maternal Hyperglycemia matter?
Maternal Hyperglycemia during pregnancy is bad / very bad for the Fetus.
•diagnosing it affords an opportunity to Prevent;
–Morbidity In the offspring “from the uterus to the grave”. children whose parents had hyperglycemia in pregnancy are more likely to be obese when they grow up and have diabetes.
–An exacerbation of the obesity & Type 2 diabetes epidemic.
–Future Type 2 diabetes in the mother; women with hyperglycemia in pregnancy have a high chance of getting diabetes in the next 10-15 years. however, there are preventative measures that can be put in place to avoid or delay the onset of the type 2 DM.
Hyperglycemia of Pregnancy
At Antenal clinics booking there are 2 groups
- Women with Normal Glucose tolerance.
- Women with Abnormal Glucose tolerance
- Known Diabetes
- Unknown Diabetes or Impaired Glucose Tolerance
*When a woman is pregnant, impaired glucose tolerant is managed as if a woman has a diagnosis of a full-blown diabetes.
Hyperglycaemia during Pregnancy
Possible Senarios
1. Pre-gestational Hyperglycaemia
–Type 1 Diabetes
–Type 2 Diabetes
- Known
- Unknown
–Monogenic Diabetes (gene-related but this is uncommon)
–Impaired Glucose Tolerance (IGT)
2. “Gestational Diabetes” (GDM)
– Any newly found Abnormal GTT after the 1st trimester of pregnancy ( i.e. Diabetes or IGT )
What is “Gestational Diabetes” (GDM)?
Practical Definitions
•WHO criteria ( and NICE)
–Diabetes OR Impaired Glucose Tolerance
- Fasting glucose =/ > 5.6 mmol/l
- 2 hour GTT glucose =/ > 7.8 mmol/l
-•International Association of Diabetes & Pregnancy Study Group (IADPSG) criteria
–Outcome based (HAPO study)
Hyperglycaemia of Pregnancy IADPSG Criteria
•75 g Glucose Tolerance test
- Fasting 5.1 mmol/l
- 1 hour 10.0 mmol/l
- 2 hours 8.5 mmol/l
Diagnose if 1 or more abnormal
Hyperglycemia during pregnancy
Consider management
- Before pregnancy
- During pregnancy
- After pregnancy
*Any degree of maternal hyperglycemia can cause serious problems for the fetus.
Stages of Pregnancy
•1st Trimester
–The phase of Organogenesis
- The body is Carefully designining the essential components of the fetal organs
- We are trying to Avoid Mistakes ( Teratogenesis)
- we are also Constructing & programming the placenta
•2nd Trimester
–Further complex development & linkage
•3rd Trimester
–Accelerated growth of the fetus
Maternal Metabolism changes
as Pregnancy progresses
Early pregnancy = Facilitated Anabolism
- Increased Insulin sensitivity
- Glucose concentration slightly lower
- Increased maternal energy stores
*at the early stage of pregnancy the mother’s blood glucose level goes down from what it used to be and thus the sensitivity to insulin goes up and because of this there is increased storage for the mother. The effect of this is that.
Later Pregnancy = Facilitated Catabolism
- increased Insulin resistance
- increased transplacental passage of nutrients
- rapid fetal growth
This is the opposite of what happens at the early stage. here you get increased insulin resistance, so the mother’s blood glucose levels go up and this increases the transplacental passage of nutrients (amino acids, fatty acid) and this is appropriate considering its not too rapid and too much.
Maternal Hyperglycaemia
How does this mess with the system?
1st Trimester
–Increased risk of Fetal abnormalities if the mother’s blood glucose is higher than it should be. This is known as Fuel Mediated Teratogenesis
–You can also get Abnormal placental programming & development such as;
- Increased risk of Pre-eclampsia
- Excessive glucose transport
Late Second & 3rd Trimester
–Excessive fat deposition and rapid growth of the fetus
–Adverse Fetal programming ( epigenetic changes ). In women with abnormal blood glucose in pregnancy, they can have methylated genes leading to the epigenetic changes.
Meningomyelocele and hyperglycemia in pregnancy
Meningomyelocele, also commonly known as myelomeningocele, is a type of spina bifida. Spina bifida is a birth defect in which the spinal canal and the backbone don’t close before the baby is born. This type of birth defect is also called a neural tube defect.
This can be caused by hyperglycemia in pregnancy.
Congenital Malformations due to Maternal hyperglycemia
- central cyanosis in congenital heart disease
- •Congenital cardiac abnormalities. i.e single ventricle and sacral dysgenesis (failure of the sacrum and associated nerve to develop), this child will never walk
- Renal Agenesis
- •Neural tube defects
Congenital Malformations in Diabetes
-The likelihood of the congenital malformation happening is depending on how bad the hypoglycemia is in the first trimester.
The risk of all congenital malformations is increased above the background population rate of 2%, even in women with type 1 diabetes with normal HbA1c concentrations. The risk increases sharply with increasingly poor blood glucose control.
Preventing Fetal Malformation in Hyperglycaemia of Pregnancy
-Good Diabetes Control in 1st Trimester. if the women turn up to the antenatal clinic after 12 weeks, this is too late.
- Prepregnancy counselling- this is to discuss sorting out their diabetes control even before they get pregnant.
2• Lifestyle Modification
3• Intensive glucose monitoring
4• If not on Insulin commence Insulin
5• Optimize Insulin Regimen
6• Basal Bolus or Pump
6• Freestyle Libre or continuous glucose monitoring
7• Folic Acid 5mg / day due to the risk of neural tube defect in women with hyperglycemia in hope that this will reduce the potential risk of neural tube problems.
Primary care & Prevention of
Fetal Malformation due to
Hyperglycaemia of Pregnancy
- Identify Unknown cases of Diabetes / IGT by checking women with risk factors
- Previous Gestational Diabetes (If you’ve had previous gestational diabetes, you are more likely to get it 2nd time around).
- Obesity
- Polycystic ovarian syndrome so strongly associated with high risk of hyperglycemia in pregnancy
- Family history of type 2 diabetes
- High risk racial group (Asian, Hispanics)
Prevention in Primary care
Recently there has been programmes that have shown improvement in glycemic levels using intensive lifestyle modification.
Hyperglycemia & Pregnancy
Problems in late second
and 3rd Trimester
- Macrosomia
- This stage of pregnancy is where the baby is growing and getting bigger and if the baby is fed too much glucose across the placenta because the mothers blood sugar is topo high and at this stage, the placenta is programmed to tr ansport more glucose to the baby. so the baby gets too many calories and get fat.
This large baby is gonna have a difficult birth (Shoulder Dystocia). the shoulder often gets trapped, they are more likely to ends up in the NICU with respiratory distress syndrome, They are also more likely to get jaundice and other things like
Hypoglycaemia (COMMONEST)
Hypocalcemia
Polycythemia
Hyperglycaemia in Pregnancy
Lifelong Fetal Sequele
sequela; a condition which is the consequence of a previous disease or injury. if fetuses are subjected to hypoglycemia in pregnancy when they grow up, they are more likely to have;
- Obesity
- Insulin resistance
- Type 2 diabetes
- Dyslipaemia
- Hypertension
- Vascular disease
- Adverse neurodevelopmental outcomes is also possible
Breast Feeding & Obesity
•Child
– Any breastfeeding reduces the risk of a child becoming obese by 30-50%.
•19 studies 3-19 years
• 6 studies 4-18 years
– Prolonged exclusive reduces obesity in a child by 67%
•Mother
–Reduces postpartum weight gain
