Quantitation of uterine activity preceding preterm, term, and postterm labor

M P Nageotte; W Dorchester; M Porto; Keegan KA Jr; R K Freeman

doi:10.1016/0002-9378(88)90353-5

Birth and Delivery · Labor and Birth

Quantitation of uterine activity preceding preterm, term, and postterm labor

Nageotte MP, Dorchester W, Porto M, Keegan KA Jr, Freeman RK

Published June 1988 American Journal of Obstetrics and Gynecology, 158(6 Pt 1), 1254-1259

DOI 10.1016/0002-9378(88)90353-5 PMID 3273360

Abstract

To assess uterine activity before labor in patients delivering preterm, at term, and postterm, the maximum spontaneous contraction frequency per 10-minute window during the initial portion of antepartum fetal heart rate monitoring was analyzed. Patients with multiple gestation, third trimester bleeding, polyhydramnios, or premature rupture of membranes and those already diagnosed with preterm labor were eliminated from the study. Of the 2446 remaining patients (7247 antepartum fetal heart rate tests) who went into spontaneous labor, 237 did so before 37 completed weeks of gestation, 1077 entered labor at term (38 to 42 completed weeks), and 1132 did so after 42 weeks. There was a significant increase in maximum uterine activity per 10-minute window from 30 to 44 weeks of gestation (average 4.7% per week; r = 0.97, p less than 0.0001). When compared with patients delivering spontaneously at term, average maximum uterine activity per 10-minute window was greatest in the preterm labor group (p less than 0.05) and least in the postterm labor group (p less than 0.05). These differences were present for several weeks preceding the onset of spontaneous labor. All three groups showed a surge of uterine activity during the 3 days before the onset of spontaneous labor.

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Birth and Delivery › Labor and Birth › Physiologic Birth · Pregnancy › Preterm Birth › Prediction

PMID 3273360 3273360 DOI 10.1016/0002-9378(88)90353-5 10.1016/0002-9378(88)90353-5 Nageotte et al. 1988, Nageotte 1988

Cite this article

Nageotte, M. P., Dorchester, W., Porto, M., Keegan, K. A., & Freeman, R. K. (1988). Quantitation of uterine activity preceding preterm, term, and postterm labor. American journal of obstetrics and gynecology, 158(6 Pt 1), 1254-1259. https://doi.org/10.1016/0002-9378(88)90353-5

Keywords

Female, Fetal Monitoring, Heart Rate, Fetal, Humans, Labor Onset/physiology, Labor, Obstetric/physiology, Postpartum Period/physiology, Pregnancy, Pregnancy Trimester, Third, Time Factors, Uterine Contraction