Blood Glucose in Pregnant Non-diabetic Women During Treatment With Betamethasone for Fetal Lung Maturation

Antenatal corticosteroid administration is an important treatment to reduce the incidence of neonatal respiratory distress syndrome, and improve neonatal outcomes of babies born premature.

Administration of betamethasone however also affects the maternal glucose homeostasis, and it is well-known that in pregnant women with diabetes, the administration of glucocorticoids can lead to significant maternal hyperglycemia, and hypoglycemia in the neonate, unless the insulin dosage is adjusted accordingly. Administration of betamethasone also affects the glucose homeostasis in pregnant non-diabetic women. However, only few studies have investigated the changes in the blood glucose levels in non-diabetic pregnant women, and a more accurate depiction of the glycemic response to betamethasone can be obtained by continuous glucose monitoring.

Recruitment of participants will occur upon their arrival with symptoms of threatened preterm birth, when it is decided to start treatment with betamethasone for fetal lung maturation.

To measure blood glucose levels in the pregnant women, a continuous glucose monitor (CGM) will be used.

Further, blood samples will be collected on days 1-6 after inclusion, for measurement of: Insulin, blood glucose, 3-hydroxybutyrat, HgbA1c, CRP and leucocytes.

Urine dipstick test for ketones and glucose will be performed twice daily. After delivery, a blood sample will be extracted from the umbilical cord for measurement of Ph, base-excess, glucose, insulin c-peptide and inflammatory markers.

Information on hypoglycemia and/or the need for early feeding of the infant after birth will be recorded.

Perspectives:

The results of this study will help us understand how the administration of betamethasone affects maternal blood glucose levels. If it is found, that administration of betamethasone causes significant hyperglycemia in the pregnant women, it may be important to measure and treat hyperglycemia during betamethasone treatment, to ensure the effect of betamethasone and prevent neonatal complications due to hypoglycemia.

• The level of insulin (pmol/L)in maternal blood before, during, and after the effect of betamethasone [Time frame: 7 days. From the day betamethasone is given untill 6 days after the first dose]
• The level of 3-hydroxybuturat (mmol/L) in maternal blood before, during and after treatment with Betamethasone [Time frame: 7 days. From the day betamethasone is given untill 6 days after the first dose]
• Level of leukocytes (White blood cell count) (mia/L) in maternal blood before, during and after treatment with betamethasone [Time frame: 7 days, from day one (the day where the first dose of betamethasone is given) untill 6 days after the first dose.]
• The level of CRP (C-reactive protein)(nmol/ml) in maternal blood before, during and after treatment with betamethasone [Time frame: 7 days. From the day betamethasone is given untill 6 days after the first dose.]
• The level of glucose (mmol/L) in umbilical cord blood at delivery [Time frame: At delivery of the baby]
• The level of insulin (pmol/L) in umbilical cord blood at delivery [Time frame: At delivery]
• The level of c-peptid (pmol/L) in umbilical cord blood at delivery [Time frame: At delivery]
• The level af adiponectin (ug/ml) in umbilical cord blood at delivery [Time frame: At delivery]
• The level of leptin (ng/ml) in umbilical cord blood at delivery [Time frame: At delivery]
• Number of infants with need for early feeding (yes/no) after birth [Time frame: First two days after birth]