Preterm uterine contractions ultimately delivered at term: safe but not out of danger

ObjectivesPatients with pregnancies complicated with premature uterine contractions (PMC), but delivered at term are considered as false preterm labor (PTL), and represent a common obstetric complication. We aimed to assess obstetric and neonatal outcomes of pregnancies complicated with PMC, but delivered at term, as compared to term normal pregnancies.Study designObstetric, maternal and neonatal outcomes of singleton pregnancies complicated with PMC between 24–336/7 weeks (PMC group), necessitating hospitalization and treatment with tocolytics and/or steroids, during 2009–2014, were reviewed. The study group included only cases who eventually delivered ≥37 weeks, which were compared to a control group of subsequent term singleton deliveries who had not experienced PMC during pregnancy. Neonatal adverse composite outcome included: phototherapy, RDS, sepsis, blood transfusion, cerebral injury, NICU admission.ResultsThe PMC group (n = 497) was characterized by higher rates of nulliparity (p = 0.002), infertility treatments (p = 0.02), and polyhydramnios (p < 0.001), as compared to controls (n = 497). Labor was characterized by higher rates of instrumental deliveries (p = 0.03), non-reassuring fetal heart rate tracings (p < 0.001) prolonged third stage of labor (p = 0.04), and increased rate of post-partum maternal anemia (Hb < 8 g/dL) p = 0.004, in the PMC group as compared to controls. Neonates in the PMC groups had lower birth weights compared to controls, 3149 g ± 429 vs. 3318 g ± 1.1, p < 0.001, respectively. By logistic regression analysis, PMC during pregnancy was independently associated with neonatal birth-weight <3rd percentile (adjusted OR 4.6, 95% CI 1.5–13.7).ConclusionsPregnancies complicated with PMC, even-though delivered at term, entail adverse obstetric and neonatal outcomes, and may warrant continued high risk follow up.