Results
In total, 1878 titles and abstracts were screened, 99 potentially
relevant studies were examined in detail (Figure 1). 63 prospective
studies (two case-control studies, 48 cohort studies, 7 cross-sectional
studies, 6 observational studies) reporting data from 6,397,310 women
met the inclusion criteria (Appendix S2). All studies reported outcomes
comparing planned mode of birth, 36 studies also reported outcomes for
emergency CS (57%), 17 studies also reported outcomes for assisted VD,
8 studies reported outcomes for planned VD vs CS for breech birth (13%)
(Appendix S2).
Based on the MOMENT score of 4 or more, 37 studies (59%) were of high
quality (Appendix S3). The primary outcome was clearly stated in 50
studies (79%), 49 studies (78%) had reproducible primary outcome
measures. 11 studies reported secondary outcomes (18%), 6 (10%)
studies had reproducible secondary outcome measures. In 51 studies
(81%), the authors explained the choice of outcomes selected. 46
studies (73%) employed methods to enhance quality of measures by
suitable training, repetition, or adjusting for confounding factors. 3
studies reported composite outcomes studying childhood adverse
neurodevelopmental outcome, neonatal morbidity outcomes, and maternal
and neonatal complications (Appendix S3) 20-22.
In total, 43 different primary outcomes and 79 different primary outcome
measures were identified; 12 different secondary outcomes and 31
secondary outcome measures were identified (Table 2). The most reported
outcomes were maternal short-term outcomes (n=26 outcomes), followed by
childhood long-term outcomes (n=11 outcomes), neonatal short-term
outcomes (n=9), maternal long-term outcomes (n=8), and subsequent
pregnancy outcomes (n=1) (Table 2).
The primary outcomes and secondary outcomes were organised into an
inventory (Table 3; Table S1 and S2). Maternal primary outcomes were
organised into broad categories (Table S1): maternal experiences and
feelings (n=11 studies), genitourinary symptoms (n=9), postpartum
complications/ morbidity (n=9), maternal experiences and feelings
(n=11), breastfeeding (n=5) and hormone levels (n=1). The most reported
primary maternal outcomes were breastfeeding (n=5 studies, 8%) and
postpartum depression (n=6 studies, 10%). Neonatal outcomes were
organised into broad categories: baseline measurements (n=10 studies)
and morbidity (n=7). The most reported outcome measurements were
baseline measurements such as SpO2, HR, cord blood pH after birth and
APGAR score (Table S1). Childhood long-term outcomes were categorised
into different health conditions (metabolic diseases, n=4; respiratory,
n=4) and neurodevelopmental outcomes (n=9 studies). Two studies looked
into maternal subsequent pregnancy outcomes (Table S1).
The secondary maternal outcomes were organised into broad categories
(Table S2): genitourinary complications (n=7 studies), maternal
experiences and feelings (n=3), maternal morbidities (n=2),
breastfeeding (n=2) and baseline measurements (n=1). The most reported
outcome was anal and urinary incontinence (n=3). Two studies reported
secondary neonatal outcomes and one study reported childhood long-term
outcomes. Various scales/ questionnaires were used to measure maternal
primary outcome measures (n=15 scales/ questionnaires), childhood
primary outcome measures (n=2), maternal secondary outcome measures
(n=5), childhood secondary outcome measure (n=1) (Table 4).