Relationship between cervical dilation and time to delivery in women with preterm labor

Developing a risk profile for spontaneous preterm birth and short interval to delivery among patients with threatened preterm labor

BACKGROUND

Threatened preterm birth is the most common reason for antepartum hospitalization in the United States, accounting for approximately 50% of these admissions. However, fewer than 10% of patients with inpatient evaluation for signs or symptoms of preterm labor ultimately deliver before term.

OBJECTIVE

This study aimed to generate predictive models to assess the risk of preterm delivery and time to delivery based on clinical signs and symptoms of patients evaluated in our institution for preterm labor concerns.

STUDY DESIGN

This was a retrospective cohort study of singleton pregnancies evaluated for signs and/or symptoms of preterm labor, including contractions, abdominal pain, vaginal bleeding, and short cervix, between 22 0/7 and 33 6/7 weeks of gestation. Inpatient evaluations were classified by patient presentation: (1) symptomatic with cervical findings (transvaginal cervical length of <2.5 cm or cervical dilation of ≥2.0 cm), (2) asymptomatic with cervical findings, and (3) symptomatic without cervical findings. The primary outcomes included incidence of spontaneous preterm birth and interval from presentation to delivery, compared between groups. The risk of preterm delivery was evaluated using log-binomial regression, and presentation to delivery timing was assessed by survival analysis and Cox proportional hazards modeling.

RESULTS

Of 631 patients with preterm labor concerns, 96 (16%) were symptomatic with cervical findings on evaluation, 51 (8%) were asymptomatic with cervical findings, and 466 (76%) were symptomatic without cervical findings. The occurrence of preterm birth was significantly higher among symptomatic patients with cervical findings (49%) than among those with cervical findings alone (31%) or symptoms alone (11%) (P<.0001). In addition, symptomatic patients with cervical findings were significantly more likely to deliver within 48 hours (20%), 1 week (30%), 2 weeks (33%), and 1 month (43%) of presentation than patients with cervical findings alone (2%, 2%, 6%, and 10%, respectively) or symptoms alone (0.4%, 1%, 1.5%, and 5%, respectively) (P value for trend<.0001). Adjusted for gestational age at presentation and previous preterm birth, the overall risk of preterm delivery was significantly higher among patients with symptoms and cervical findings than among patients with cervical findings alone (relative risk, 2.81; 95% confidence interval, 1.74-4.54) or symptoms alone (relative risk, 4.39; 95% confidence interval, 3.16-6.09). Adjusted for the same variables, symptomatic patients with cervical findings were also at higher risk of delivery over time after assessment than patients with cervical findings alone (hazard ratio, 2.06; 95% confidence interval, 1.47-2.90) or symptoms alone (hazard ratio, 2.16; 95% confidence interval, 1.74-2.70). The negative predictive value of these models suggested that only 1% of patients with isolated symptoms or cervical findings are at risk of preterm delivery within 1 week of initial presentation.

CONCLUSION

Symptomatic patients with cervical findings suggestive of preterm labor were at the greatest risk of preterm birth and a shorter interval from presentation to delivery. The study findings supported a risk profile that may facilitate the selection of patients most appropriate for admission and targeted management. Nonetheless, as nearly 50% of patients meeting this risk profile subsequently deliver at term, future research is needed to identify which of these patients will require intervention.

Preterm Labor and Birth: A Clinical Review

When caring for women experiencing preterm labor and birth, nurses play a significant role as bedside experts, advocates, patient educators, and key members of the maternity care team. Enhanced expertise on clinical and professional knowledge of preterm labor and birth is crucial in prevention and treatment. As preterm birth rates continue to rise, perinatal nurses as well-informed clinical experts have the opportunity to offer innovative education, holistic assessments, and communication through shared decision-making models. Educating pregnant women about early recognition of preterm labor warning signs and symptoms allows for timely diagnosis, interventions, and treatment. Informed and collaborative nursing practice improves quality of clinical care based on individualized interactions. A clinical review of preterm labor and preterm birth is presented for perinatal nurses.

The effect of evening primrose oil on labor induction and cervical ripening: A systematic review and meta-analysis

The evening primrose oil has prostaglandin effects and is applied to soften the cervix. This systematic review and meta-analysis aimed to establish the results of clinical trials performed on the effect of evening primrose oil on labor induction and cervical ripening in pregnant women. Research studies were searched from 1990 to September 2019 in Pubmed, Science Direct, Embase, and Cochrane Library using the keywords: cervical ripening, Bishop score, labor induction, post-term pregnancy, evening primrose, and any possible combination of these keywords (Farsi, English). Data analysis was conducted using STATA (version 14.1), and I² index and random effect forest plots to assess the heterogeneity between the studies and perform the meta-analysis, respectively. Six articles that met the inclusion criteria were extracted in which four were entered into quantitative meta-analysis. The results' high heterogeneity was 91.4% based on I² index (p ≤ .001) and the random model was applied for meta-analysis. The result demonstrated no significant difference between the intervention and control groups in terms of mean difference of the Bishop score before and after intervention (SMD: 0.27, 95%CI: -0.41, 0.96, p = .43). Based on current meta-analysis on four studies, effectiveness of oral consumption of evening primrose on cervical ripening was not approved.

Outcome of labor among women admitted at advanced cervical dilatation

Objective: To identify in our setting the outcome of labor among women admitted at advanced cervical dilatation.Methods: This prospective cohort study was carried out between 1 December 2015 and 31 March 2016. Women carrying live term singletons in vertex presentation admitted with a cervical dilatation >5 cm (late arrival group) or ≤5 cm (early arrival group) were followed up till delivery. The main variables studied included mode of delivery, genital lacerations, and postpartum hemorrhage (PPH). Data from women in both groups were compared. Fisher's exact test and t-test were used for comparison. p < .05 was considered statistically significant.Results: Late arrival in the labor ward was observed in 52.5% of women (126/240). Late arrival in the labor ward was significantly associated with a reduction in the cesarean section (CS) risk (Relative risk (RR) 0.34, 95%CI 0.12-0.94), but with an increased risk of lower genital tract lacerations (RR 2.3, 95%CI 1.3-3.8), PPH (RR 4.5, 95%CI 1.04-20.2), and admission of the newborn in the neonatal intensive care unit for neonatal asphyxia or infection (RR 3.6, 95%CI 1.04-12.5).Conclusion: Late arrival in the labor ward was associated with an increased risk of maternal and neonatal morbidity. Therefore, women should be encouraged to arrive early in the labor ward.