Do maternal factors influence neonatal thyroid status in the extreme premature infant?
Neonatal thyroid status in extreme preterm infants is independently affected by gestation and not maternal factors such as route of delivery, exogenous maternal glucocorticoid administration, third trimester maternal FT4, presence or absence of chorioamnionitis, smoking status, BMI, TPO status or haemoglobin levels. The severity of neonatal hypothyroxinaemia increases with lower gestational age.
We did find a relationship between the use of antibiotics and breakthrough pregnancy in a population-based prescription database. The results did not hold for broad-spectrum antibiotics or in a sensitivity analysis. The results are partly not the same as those found in a pharmacoepidemiological study with a similar design using two US pregnancy databases. Both studies can suffer from bias and confounding, but these will be different because of the use of different databases.