OBJECTIVE To assess the value of the autopsy findings on a series of infants dying with features of the oligohydramnios sequence, with particular reference to anomalies of the renal tract. METHODS Retrospective review. METHODS Pathology departments serving three maternity units in Manchester. METHODS Eighty-nine infants having an autopsy examination between 1976 and 1990. RESULTS Thirty-two (34%) infants had bilateral renal agenesis, 30 (34%) had bilateral cystic dysplasia, eight (9%) had unilateral agenesis with unilateral cystic dysplasia, four (4%) had renal histology characteristic of a recessively inherited disorder (two cases of renal tubular dysgenesis and two cases of autosomal recessive (infantile) polycystic disease), nine (10%) had minor urinary tract anomalies, and three (3%) had morphologically normal renal tracts. Forty-eight (54%) infants had congenital abnormalities other than those resulting from oligohydramnios sequence; most commonly, these were anomalies of the sporadic VATER association, but in four infants the extra renal anomalies present allowed recognition of a recessively inherited syndrome (Meckel's in three cases, Smith-Lemli-Opitz in one). CONCLUSIONS A detailed autopsy is vital in assessment of infants with oligohydramnios sequence resulting from a congenital abnormality of the kidneys or urinary tract. This applies equally to second trimester fetuses following miscarriage or therapeutic abortion, to stillborn infants, or to neonatal deaths.