ABSTRACT
Neurological complications are more common in multiple pregnancies. This truism has been discussed in a chapter of a previous edition of the Fetus as a Patient series1 and in a recent review2. Critical reading of the published data suggests that conclusions related to neurological damage in neonates need to be considered with some caution. Hospital-or institution-based series include more detailed information, but quite often do not have enough statistical power for meaningful conclusions to be drawn. This is particularly true for descriptions of rare conditions or interventions, which do not comprise enough cases unless based on multi-center studies or unless compiled over a long time interval. On the other hand, population-based studies usually lack sufficient details. These analytical problems are further complicated by the difficulty in retrospective identification of antenatal causes of cerebral palsy in an individual case3. Another deficiency is that, in many cases, outcomes are either unknown or incomplete, because cases are lost to follow-up. Finally, studies usually discuss the most severe forms of neurological injury, i.e. cerebral palsy, and often do not consider other complications such as blindness, learning difficulties and subnormal scores of cognitive and motor skills.
