Aim: To establish prevalence of antenatally acquired haemorrhagic-ischaemic (HI) lesions among preterm infants < 34 wks GA and to compare their antenatal and obstetrical risk factors with those of infants with similar lesions of postnatal onset.

Subjects: 1234 infants were studied prospectively, using serial cranial US. The entry criteria for antenatal onset (Group A) were: a) extensive cysts (n=7) or b) a porencephalic cyst < 3 d (n=1); c) pre-cystic lesions confirmed to be white matter damage at autopsy (n=4), d) symmetric thalamic lesions (n=2) and e) subependymal pseudocysts (n=14). Group B were those with an initial normal US with subsequent development of a-d type of lesions. Results: Only 35 (2.9%) met the entry criteria for group A and 83 for group B. On comparison of obstetrical risk factors between these two groups a significant difference for GA was found (31.3 versus 28.8; p=0.0003). Significant more abnormal CTGs were found in group A (p=0.006), also after logistic regression analysis and significant more PROM was found in group B (p=0.02).

Conclusion: Antenatal onset of HI lesions is not common in preterm infants. CTGs can be abnormal, often leading to emergency CS, in infants with well established brain lesions.