Intracervical Foley catheter plus intravaginal misoprostol compared to intravaginal misoprostol-only for cervical ripening: A systematic review and meta-analysis

Duration of Induction of Labor for Second-Trimester Medication Abortion and Adverse Outcomes

OBJECTIVE

To evaluate the relationship between duration of labor during second-trimester medication abortion and adverse outcomes.

METHODS

We conducted a retrospective cohort study including all individuals with a singleton gestation undergoing second-trimester medication abortion without evidence of advanced cervical dilation, rupture of membranes, or preterm labor at four centers. The primary exposure was duration of labor (ie, hours spent from receiving misoprostol to fetal expulsion). The primary outcome was composite morbidity , defined as uterine rupture, need for blood transfusion, clinical chorioamnionitis, intensive care unit admission, or need for readmission. We performed bivariate and multivariate negative binomial analyses. A post hoc subgroup analysis was performed to assess for the risk of the primary outcome by gestational age. We performed tests of homogeneity based on history of uterine scarring and parity.

RESULTS

Six hundred eighty-one individuals were included. The median duration of labor was 11 hours (interquartile range 8-17 hours). One hundred thirty-one (19.2%) experienced the primary outcome. When duration of labor was evaluated continuously, a longer duration of labor was associated with an increased frequency of morbidity (adjusted β=0.68, 95% CI, 0.32-1.04). When duration of labor was evaluated categorically, those experiencing the highest quartile of duration (ie, 17 hours or more) had a statistically higher risk for experiencing morbidity compared with individuals in all other quartiles (adjusted relative risk 1.99, 95% CI, 1.34-2.96). When we focused on components of the composite outcome, clinical chorioamnionitis was significantly different between those experiencing a longer duration and those experiencing a shorter duration of labor (26.2% vs 10.6%, P <.001). On subgroup analysis, gestational age was not associated with the risk of composite morbidity. Tests of homogeneity demonstrated no significant difference in the risk for morbidity among individuals with a history of uterine scarring or based on parity.

CONCLUSION

Duration of labor was independently associated with risks for adverse maternal outcomes during second-trimester medication abortion, specifically clinical chorioamnionitis.

The use of adjunctive mechanical dilation at the time of induction termination and adverse health outcomes: a systematic review

OBJECTIVE

This study aimed to assess if the use of mechanical dilation at the time of induction termination is associated with changes in the time from initiation of labor to expulsion of the fetus (induction-to-expulsion interval) and with the frequency of health complications when compared with medication management alone.

DATA SOURCES

PubMed, CINAHAL, Scopus, and the Cochrane Central Register of Controlled Trials were queried from January 2000 to May 2023.

STUDY ELIGIBILITY CRITERIA

We included randomized controlled trials of individuals who were assigned to undergo mechanical dilation (ie, laminaria, Dilapan-S, and intracervical Foley balloon catheter) in combination with the use of medication and compared it with the outcomes of medication use (eg, prostaglandins, antiprogestins, oxytocin) alone.

METHODS

The primary outcome was the induction-to-expulsion interval. The secondary outcomes were the incidence of clinical chorioamnionitis, sepsis, hemorrhage, the need for blood transfusion and uterotonics, cervical laceration, the need for adjunctive procedures (eg, dilation and curettage), failed induction termination, uterine rupture, intensive care unit admission, or death. Assessment of bias was performed using the Cochrane Risk of Bias tool. A subgroup analysis was performed among studies deemed to be at low risk of bias.

RESULTS

Of 864 abstracts identified, 11 met the inclusion criteria. Five studies demonstrated a shorter induction-to-expulsion interval among those randomized to mechanical dilation, whereas 6 studies demonstrated a similar or longer induction-to-expulsion interval. There were no significant differences reported in the frequency of any adverse outcomes between the trial arms. In addition, most studies (8/11) exhibited moderate to high levels of bias. In an analysis of the 3 studies deemed to have a low risk of bias, 1 (n=60) demonstrated a longer induction-to-expulsion interval with adjunctive laminaria, 1 (n=60) demonstrated a shorter induction-to-expulsion interval with adjunctive intracervical Foley balloon catheter use, and 1 demonstrated no difference in the induction-to-expulsion interval with adjunctive Dilapan-S use (n=180).

CONCLUSION

Only a small number of studies, most of which were of low quality, assessed mechanical dilation for induction termination. The results of these studies were inconsistent in terms of the induction-to-expulsion interval of adjunctive mechanical methods in comparison with medication management alone. Studies did not reveal significant differences between the groups in adverse outcomes. Further research should investigate the use of mechanical dilation at the time of induction termination using high-quality methods.