Long-term effects of labor and delivery on offspring: a matched-pair analysis.

An investigation was undertaken in an effort to learn whether the type of delivery or the pattern of labor progression has any lasting effect on the infant. Paired-data design was chosen to ensure that the comparisons between homogeneous groups would be valid. Our objective was to reduce potential bias based on unequal distribution of patient characteristics that might be more or less commonly associated with abnormal labors or with difficult deliveries. Seven-year intelligence quotient data for matched pairs of cases showed significant long-range adverse impact from midforceps operations but not from low-forceps procedures. Comparable paired-data analysis for the effect of labor disorder on the infant verified a similar deleterious influence from both arrest and protraction patterns.