The Morbidity of the 34- to 35-Week Gestation: Should We Reexamine the Paradigm?

Algorithms for the management of preterm labor avoid the use of tocolysis beyond 34 weeks' gestation, based in large part on low respiratory morbidity found at this gestational age. We sought to delineate the morbidities, not just respiratory, of this age group in a modern neonatal intensive care unit setting. We prospectively looked at hospital resource use and general morbidity in a consecutive 2-year cohort of 34-weekers at our hospital. The concurrent consecutive 35-week cohort was used as a control. Data were prospectively collected from obstetricians and bedside records. Compared with 35-weekers, the 34-week group had similar obstetric characteristics. Significant differences were seen in use of oxygen, nasal continuous positive airway pressure, methylxanthines, home apnea monitoring, antibiotics, and phototherapy. The 34-week group took longer to come off intravenous lines and were discharged later. Overall, they used approximately twice the resources of the 35-week group. To stop or not use tocolysis at 34 weeks' gestation based mainly on low respiratory morbidity ignores the significant other morbidities. These findings suggest a reconsideration of the paradigm regarding 34-week gestation as a cutoff point in decision making.

KEYWORDS

Prematurity - tocolysis - neonatal morbidity

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