Methodological problems in a study of fetal visual perception.

Reid et al.[1] analysed data from 39 third-trimester fetuses, concluding that they showed a preferential head-orienting reaction towards lights projected through the uterine wall in a face-like arrangement, as opposed to an inverted triangle of dots. These results imply not only that assessment of visual-perceptive responses is possible in prenatal subjects, but also that a measurable preference for faces exists before birth. However, we have identified three substantial problems with Reid et al.'s [1] method and analyses, which we outline here.