Pregnancy outcome in South Australia:Population and cohort studies

Abstract

Adverse pregnancy outcome, including preterm birth, small for gestational age, gestational diabetes mellitus and hypertensive disorders of pregnancy affect a quarter of first pregnancies, but their pathophysiology is not fully understood. The studies presented in this thesis describe long-term trends, sexual dimorphism, seasonality of these adverse pregnancy outcome and maternal haemodynamics in pregnancy in South Australia. - In many Western countries, such as (South) Australia, the preterm birth rate has increased, mostly due to increased iatrogenic delivery, particularly in pregnancies complicated by hypertensive disorders of pregnancy, small for gestational age, and preterm prelabour rupture of the membranes. This was also seen in South Australia. However, overall and preterm stillbirth rates have declined. - Fetal sex is an independent risk factor for adverse pregnancy outcome. A male disadvantage is observed in most but not all adverse pregnancy outcomes. - The incidence of gestational diabetes mellitus and hypertensive disorders of pregnancy in South Australia showed seasonality. Winter conceptions had higher gestational diabetes mellitus rates, while gestational diabetes mellitus rates were the lowest for summer conceptions. Meanwhile, spring conceptions had higher hypertensive disorders of pregnancy rates, while hypertensive disorders of pregnancy rates were the lowest for autumn conceptions. New perspectives in exposures with these conditions can be sought in periodicity. - Maternal haemodynamic maladaptation to pregnancy differs between subtypes of hypertensive disorders of pregnancy, indicating a different pathophysiology between these subtypes. Being intermittent hypertensive in pregnancy is not benign. Monitoring haemoynamic adaptation throughout pregnancy could potentially identify women at risk for hypertensive disorders of pregnancy