Método de clasificación de mortinatos según condición obstétrica relevante de la muerte fetal, en un hospital público de Chile (Método CORM) / A new fetal death classification system

Background: Stillbirth is the mayor contributor to perinatal mortality. Aim: To report a system for classification of fetal deaths. Material and Methods: Retrospective cohort study of 29,916 births with 258 fetal deaths that occurred in a public hospital. Data were obtained from audit reports of stillbirths. The method for classification “obstetric condition relevant to the death” was applied, based on obstetric and placental pathological findings analyzed exclusively by a single obstetrician and a single pathologist. Results: Ninety two percent of obstetric conditions causing fetal death were identified. The most commonly reported were ascending bacterial infection in 26%, congenital anomalies in 19%, arterial hypertension in 12% and placental pathology in 12%. Fetal growth restriction was identified in 50% of stillbirths. Ninety percent were secondary to a primary obstetric condition and 10% had an unexplained cause. Placental abruption as the final cause of fetal death was identified in 60% of cases with arterial hypertension, 43% of cases with placental pathology and 37% of ascending infections. Fetal deaths occurred during pregnancy in 82% of cases and during labor in 17%. Intrapartum asphyxia occurred in 0.8% of stillbirths and presented in term pregnancies. Conclusions: The “obstetric condition relevant to the death” method for classification of fetal death is effective to identify the originating obstetric cause of stillbirth and reduces the impact of fetal growth restriction and intrapartum asphyxia as the leading causes of death.

Factores asociados con el parto prematuro entre 22 y 34 semanas en un hospital público de Santiago / Risk factors for preterm deliveries in a public hospital

Background: Preterm births are responsible for 75 to 80% of perinatal mortality. Aim: To determine the factors associated with preterm births, using maternal clinical data, laboratory results and pathological placental findings. Patients and Methods: Retrospective study of 642 preterm single births at 22-34 weeks' gestation. Four hundred and seven cases with pathological placental studies were included. Births were subdivided into preterm births as a consequence of a medical indication and spontaneous births with or without premature rupture of membranes (PROM). Risk factors for preterm births were classified as maternal, fetal, placental, indeterminable and unclassifiable. Results: The proportions of preterm births were spontaneous 69% (with PROM 27% and with intact membranes 42%) and medically indicated births 31%. A risk factor associated with prematurity was identified in 98 and 85% of medically indicated and spontaneous births, respectively. Ascending bacterial infection (ABI) was the most frequently associated factor with spontaneous preterm delivery in 51% of women (142/280, p < 0.01) and with preterm births of less than 30 weeks in 52% of women (82/157, p < 0.01). Vaginal or urinary infection with Group B Streptococcus, was the most common clinical condition associated with ABI related deliveries. Hypertension was present in 94 of 127 medically indicated preterm deliveries (preeclampsia in 62% and chronic hypertension in 12%), and in 29% (preeclampsia 24%) of preterm births of more than 30 weeks. Congenital anomalies were mainly associated with a maternal age over 35 years in 15% (14/92) of women. The frequency of placental diseases was higher in spontaneous preterm deliveries (14%) and in pregnancies of more than 30 weeks in (14%). Conclusions: ABI was the most common factor associated with spontaneous preterm births at 2234 weeks, while preeclampsia is the most common factor associated with medically indicated preterm births.