Objective: To determine the incidence of respiratory problems and lung volume abnormalities in babies born after first trimester amniocentesis or chorion villus sampling.
Design: A prospective randomized study.
Setting: Harris Birthright Research Centre for Fetal Medicine, Paediatric Respiratory Laboratory, King's College Hospital.
Subjects: Babies of mothers who had undergone first trimester amniocentesis (n = 74) or chorion villus sampling (CVS) (n = 86) for fetal karyotyping because of advanced maternal age, parental anxiety or family history of chromosomal abnormality in the absence of parental chromosome re-arrangement.
Main outcomes: Respiratory distress in the neonatal period and lung volume as assessed by measurement of functional residual capacity (FRC).
Results: CVS was associated with a significantly higher incidence of neonatal respiratory distress, six infants in the CVS group but none in the amniocentesis group required admission to the special care baby unit because of respiratory distress (P less than 0.05). Although there was no significant difference in the mean FRC between the two groups (amniocentesis 29.7 ml/kg vs CVS 29.6 ml/kg) the overall incidence of FRC values less than 2.5th centile of the normal range was 9%.
Conclusion: Both amniocentesis and CVS performed in the first trimester of pregnancy may impair antenatal lung growth.