Research summaries for normal birth.

In this column, the author summarizes four research studies relevant to normal birth. The studies summarized include a systematic review of trials evaluating the benefits versus harms of routine artificial rupture of the membranes; a study of the effect of continuous female labor support by a minimally trained family member or friend on attachment and early parenting; a systematic review examining the relationship between cesarean surgery and postpartum urinary incontinence; and a randomized controlled trial of warm perineal compresses during the second stage of labor.