A comparison of neonatal morbidity: is fetal lung maturity testing effective?

Abstract

RITY TESTING EFFECTIVE? MARY BRAY, MONIQUE HO, BRIAN BROST, Medical College of Ohio, OB/GYN, Toledo, OH University of Alabama at Birmingham, Human Genetics, Birmingham, AL Mayo Clinic, Obstetrics and Gynecology, Rochester, MN OBJECTIVE: Evaluation of the benefit of fetal lung maturity (FLM) testing for delivery management between 34 and 36 weeks gestation. STUDY DESIGN: Prospective cohort of 502 consecutive high risk gravidas presenting for delivery management between 34 and 36 weeks gestation during 1991-1999. Incidences of neonatal morbidities (RDS, IVH, seizures, TTN, congenital pneumonia, NEC, ophthalmalogic disease, death, and length of stay) were compared between those who had undergone testing and those who had not. Comparison was also made between those who tested mature and immature. Analysis was controlled for delivery gestational age, maternal age, parity, and multiple gestation. RESULTS: 94 (18.7%) of the studied gravidas underwent FLM testing, the remaining 408 did not. 74 test results were mature, 20 immature. There was no significant difference in either single or combined neonatal morbidity between those tested and not tested (p = .71). Of those who had amniocentesis for FLM testing, the overall morbidity rate was decreased in those who had a mature result (p = .03). When stratified by gestational age, only the 34 week group retained significance (p = .04). Comparison of individual morbidity incidences in those who tested mature vs. immature showed only a decrease in RDS for the mature group (p < .001). CONCLUSION: Although overall neonatal morbidity did not change in the group of patients who were managed without FLM testing, there was a decrease in RDS for those who testedmature at 34 weeks. This suggests that amniocentesis for FLM may be a useful management decision tool for this gestational age, but perhaps not for pregnancies at 35-36 weeks.