The use of bubble charts in analyzing the global second-stage cesarean delivery rates: a systematic review

Abstract

Objective: This study aimed to systematically review the worldwide second-stage cesarean delivery rate concerning pre-second-stage cesarean delivery and assisted vaginal birth rates.

Data sources: PubMed, Medline Ovid, EBSCOhost, Embase, Scopus, and Google Scholar were queried from inception to February 2023, with the following terms: "full dilatation," "second stage," and "cesarean," with their word variations. Furthermore, an additional cohort of 353,434 cases from our recently published study was included.

Study eligibility criteria: Only original studies that provided sufficient information on the number of pre-second-stage cesarean deliveries, second-stage cesarean deliveries, and vaginal births were included for the calculation of different modes of delivery. Systemic reviews, meta-analyses, or case reports were excluded.

Methods: Study identification and data extraction were independently performed by 2 authors. Selected studies were categorized on the basis of parity, study period, and geographic regions for comparison.

Results: A total of 25 studies were included. The overall pre-second-stage cesarean delivery rate, the second-stage cesarean delivery rate, and the second-stage cesarean delivery-to-assisted vaginal birth ratio were 17.94%, 2.65%, and 0.19, respectively. Only 5 studies described singleton, term, cephalic presenting pregnancies of nulliparous women, and their second-stage cesarean delivery rates were significantly higher than those studies with cohorts of all parity groups (4.50% vs 0.83%; P<.05). In addition, the second-stage cesarean delivery rate showed a secular increase across 2009 (0.70% vs 1.05%; P<.05). Moreover, it was the highest among African studies (5.14%) but the lowest among studies from East Asia and South Asia (0.94%). The distributions of second-stage cesarean delivery rates of individual studies and subgroups were shown with that of pre-second-stage cesarean delivery and assisted vaginal birth using the bubble chart.

Conclusion: The overall worldwide pre-second-stage cesarean delivery rate was 17.94%, the second-stage cesarean delivery rate was 2.65%, and the second-stage cesarean delivery-to-assisted vaginal birth ratio was 0.19. The African studies had the highest second-stage cesarean delivery rate (5.14%) and second-stage cesarean delivery-to-assisted vaginal birth ratio (1.88), whereas the studies from East Asia and South Asia were opposite (0.94% and 0.11, respectively).

Keywords: cesarean delivery; full dilatation; second stage.

Figure 1

The PRISMA flowchart AJOG, American Journal of Obstetrics & Gynecology; PRISMA, Preferred Reporting Items for Systematic Reviews and Meta-Analyses.

Figure 2

The bubble chart showing the rates of different modes of delivery A, Group A consists of studies focusing on singleton, term, cephalic presenting pregnancies of all parities. B, Group B consists of studies focusing on singleton, term, cephalic presenting pregnancies of nulliparous patients. C, Group C consists of studies that have not specified the number of fetuses, gestation, or presentation. The “x” symbol indicates that information on AVB is not available for calculation of the ssCD–to–AVB ratio. For articles that had excluded elective CD, their bubbles were circled with dotted lines. The green color indicates African studies. The yellow color indicates Australian studies. The blue color indicates East Mediterranean studies. The purple color indicates East Asia or South Asia studies. The orange color indicates North America studies. The red color indicates Western Europe studies. AVB, assisted vaginal birth; CD, cesarean delivery; ssCD, second-stage cesarean delivery.

Figure 3

The bubble chart showing the pre–ssCD and ssCD rates and the ssCD–to–assisted vaginal birth ratio of the studies grouped by their study periods CD, cesarean delivery; ssCD, second-stage cesarean delivery.

Figure 4

The bubble chart showing the pre–ssCD and ssCD rates and the ssCD–to–assisted vaginal birth ratio stratified of the included studies grouped by geographic distribution CD, cesarean delivery; ssCD, second-stage cesarean delivery.