[Risk factors for birth injuries].

OBJECTIVE: To identify risk factors associated with birth trauma.

SETTING: Servicio de Neonatología, Hospital General "Dr. Manuel Gea González", Secretaría de Salud.

DESIGN: Case-control, prolective study.

PATIENTS: There were 129 cases and 134 controls.

MEASURES: We recorded the following variables: a) maternal and delivery: age, weight, height, prenatal care, pre-existing disease or gestational disease, mode of delivery, anesthetic management during labor, use of external maneuvers or forceps; b) newborn: birth weight, gestational age, academic degree of attendant physician at delivery, and type of birth injury.

RESULTS: The independent risk factors associated to birth injury were: for ecchymoses; general anesthesia (OR 13.7, 95% CI = 3 - 62.6), breech presentation (OR 6.4, 95% IC 95% = 1.4 - 27.9) and gestational age < or = 32 weeks (OR 6.4, 95% CI = 1.3 - 31.1); for lacerations, vaginal dystocic delivery or cesarean section (OR 19, 95% CI = 4.4 - 81.1) and use of external maneuvers (OR 5.6, 95% CI = 1.5 - 21.6); for cephalhematoma maternal height < or = 1.54 m (OR 7.4, 95% CI = 2.3 - 23.7) and external maneuvers (OR 7.2, 95% CI = 2.3 - 23.7); for caput succedaneum, external maneuvers (OR 3.4, 95% CI = 1.5-7.7) and maternal age < or = 19 or > or = 36 years (OR 3.0, 95% CI = 1.4 - 6.4).

CONCLUSIONS: Risk factors associated with birth injuries identified in this study involved maternal conditions, neonatal conditions and mechanism of delivery.