Refining the clinical definition of active phase arrest of dilation in nulliparous women to consider degree of cervical dilation as well as duration of arrest.: Short title: Clinically defined active phase arrest of labor.
Refining the clinical definition of active phase arrest of dilation in nulliparous women to consider degree of cervical dilation as well as duration of arrest.: Short title: Clinically defined active phase arrest of labor.
- 2021
BACKGROUND: Maternal and neonatal outcomes associated with duration of arrest of dilation beyond 4 hours are not well known. In addition, the current definition of arrest does not consider the degree of cervical dilation (6 cm vs. 7 cm vs. 8 cm vs. 9 cm) when arrest occurs. CONCLUSION: When cervical dilation is 6 or 7 cm, allowing arrest of dilation 4 hours or longer is reasonable since it was not associated with increased risks of adverse neonatal outcomes. When cervical dilation is 8 or 9 cm, the benefit of allowing arrest of dilation 4 hours or longer should be balanced against the risk of adverse maternal and neonatal outcomes. Copyright (c) 2021. Published by Elsevier Inc. OBJECTIVE: We sought to examine maternal and neonatal outcomes in nulliparous women who achieved the active phase of labor according to the duration they required to achieve at least 1 cm of cervical change (less than 4 hours vs. 4-5.9 hours vs 6 hours or greater) beginning at 6, 7, 8 and 9 cm. RESULTS: Of 31,505 nulliparous women included in this study, 13,142 (42%), 10,855 (34%), 11,761 (37%), and 17,049 (54%) reached documented cervical dilation of 6, 7, 8, and 9 cm, respectively. At cervical dilation of 6 or 7 cm, arrest of dilation less than 4 hours compared to 4-5.9 hours was associated with decreased risks of adverse maternal outcomes. When cervical dilation was 8 or 9 cm, arrest of dilation less than 4 hours compared to 4-5.9 hours was associated with decreased risks of adverse maternal and neonatal outcomes. For example, women starting at 8 cm cervical dilation who required less than 4 hours to achieve 1 cm of cervical change compared to those who required 4-5.9 hours had lower rates of cesarean delivery (aOR 0.40; 95%CI 0.28-0.55), chorioamnionitis (aOR 0.42; 95%CI 0.29-0.60), and the neonatal composite outcome (aOR 0.51; 95%CI 0.36-0.72). STUDY DESIGN: This was a retrospective cohort study of nulliparous women with term singleton cephalic pregnancies in spontaneous or induced active labor (6 cm or greater). To evaluate the effect of labor duration on maternal and fetal outcomes at different degrees of cervical dilation, we categorized women based on time intervals they required to achieve at least 1 cm of cervical change after membrane rupture ("less than 4 hours," "4-5.9 hours," and "6 hours or greater"), and we correlated each time interval with referent cervical dilation status (6 cm, 7 cm, 8 cm and 9 cm). Maternal and neonatal outcomes were analyzed according to the duration to progress at least 1 cm starting from each degree of cervical dilation. Our primary outcome was a composite of neonatal outcomes, including intensive care unit admission, neonatal death, seizure, ventilator use, birth injury, and neonatal asphyxia. We also examined maternal outcomes. Adjusted odds ratios (aORs) with 95% confidence intervals (95%CIs) were calculated, controlling for predefined covariates.
English
0002-9378
10.1016/j.ajog.2021.03.029 [doi] S0002-9378(21)00209-X [pii]
*Labor Stage, First
*Obstetric Labor Complications
*Parity
Adult
Cesarean Section/sn [Statistics & Numerical Data]
Chorioamnionitis/ep [Epidemiology]
Cohort Studies
Female
Humans
Pregnancy
Retrospective Studies
Time Factors
MedStar Health Research Institute
MedStar Washington Hospital Center
Maternal-Fetal Medicine Fellowship
Obstetrics and Gynecology/Maternal-Fetal Medicine
Journal Article
BACKGROUND: Maternal and neonatal outcomes associated with duration of arrest of dilation beyond 4 hours are not well known. In addition, the current definition of arrest does not consider the degree of cervical dilation (6 cm vs. 7 cm vs. 8 cm vs. 9 cm) when arrest occurs. CONCLUSION: When cervical dilation is 6 or 7 cm, allowing arrest of dilation 4 hours or longer is reasonable since it was not associated with increased risks of adverse neonatal outcomes. When cervical dilation is 8 or 9 cm, the benefit of allowing arrest of dilation 4 hours or longer should be balanced against the risk of adverse maternal and neonatal outcomes. Copyright (c) 2021. Published by Elsevier Inc. OBJECTIVE: We sought to examine maternal and neonatal outcomes in nulliparous women who achieved the active phase of labor according to the duration they required to achieve at least 1 cm of cervical change (less than 4 hours vs. 4-5.9 hours vs 6 hours or greater) beginning at 6, 7, 8 and 9 cm. RESULTS: Of 31,505 nulliparous women included in this study, 13,142 (42%), 10,855 (34%), 11,761 (37%), and 17,049 (54%) reached documented cervical dilation of 6, 7, 8, and 9 cm, respectively. At cervical dilation of 6 or 7 cm, arrest of dilation less than 4 hours compared to 4-5.9 hours was associated with decreased risks of adverse maternal outcomes. When cervical dilation was 8 or 9 cm, arrest of dilation less than 4 hours compared to 4-5.9 hours was associated with decreased risks of adverse maternal and neonatal outcomes. For example, women starting at 8 cm cervical dilation who required less than 4 hours to achieve 1 cm of cervical change compared to those who required 4-5.9 hours had lower rates of cesarean delivery (aOR 0.40; 95%CI 0.28-0.55), chorioamnionitis (aOR 0.42; 95%CI 0.29-0.60), and the neonatal composite outcome (aOR 0.51; 95%CI 0.36-0.72). STUDY DESIGN: This was a retrospective cohort study of nulliparous women with term singleton cephalic pregnancies in spontaneous or induced active labor (6 cm or greater). To evaluate the effect of labor duration on maternal and fetal outcomes at different degrees of cervical dilation, we categorized women based on time intervals they required to achieve at least 1 cm of cervical change after membrane rupture ("less than 4 hours," "4-5.9 hours," and "6 hours or greater"), and we correlated each time interval with referent cervical dilation status (6 cm, 7 cm, 8 cm and 9 cm). Maternal and neonatal outcomes were analyzed according to the duration to progress at least 1 cm starting from each degree of cervical dilation. Our primary outcome was a composite of neonatal outcomes, including intensive care unit admission, neonatal death, seizure, ventilator use, birth injury, and neonatal asphyxia. We also examined maternal outcomes. Adjusted odds ratios (aORs) with 95% confidence intervals (95%CIs) were calculated, controlling for predefined covariates.
English
0002-9378
10.1016/j.ajog.2021.03.029 [doi] S0002-9378(21)00209-X [pii]
*Labor Stage, First
*Obstetric Labor Complications
*Parity
Adult
Cesarean Section/sn [Statistics & Numerical Data]
Chorioamnionitis/ep [Epidemiology]
Cohort Studies
Female
Humans
Pregnancy
Retrospective Studies
Time Factors
MedStar Health Research Institute
MedStar Washington Hospital Center
Maternal-Fetal Medicine Fellowship
Obstetrics and Gynecology/Maternal-Fetal Medicine
Journal Article