Mediolateral episiotomy and risk of obstetric anal sphincter injuries and adverse neonatal outcomes during operative vaginal delivery in nulliparous women: a propensity-score analysis

Table 4 Association between mediolateral episiotomy and the condition of infant at birth (pH umbilical artery < 7.10, 5-min Apgar score < 7) according to the type of operative vaginal delivery and fetal distress status (2013–2017)

	Total number^†	Mediolateral episiotomy		No Mediolateral episiotomy		RR (95% CI)
	Total number^†	n	pH umbilical artery < 7.10 or 5-min Apgar score < 7, n (%)	n	pH umbilical artery < 7.10 or 5-min Apgar score < 7, n (%)	Univariate analysis ^*	Using IPTW ^*
Forceps/spatula delivery
Fetal distress	453	257	7 (4.2)	288	39 (13.5)	0.40 (0.16–0.98)	0.52 (0.31–0.89)
No fetal distress	688	274	13 (3.6)	414	23 (5.6)	0.80 (0.37–1.74)	0.70 (0.41–1.20)
Vacuum delivery
Fetal distress	1008	228	21 (9.2)	780	112 (14.4)	0.83 (0.51–1.36)	0.89 (0.68–1.17)
No fetal distress	1434	298	14 (4.7)	1136	71 (6.3)	0.81 (0.45–1.47)	1.06 (0.77–1.48)

RR risk ratio, CIs confidence intervals, IPTW inverse probability of treatment weighting. ^* Mixed model after multiple imputation of missing data. ^† Missing data – mode of operative vaginal deliveries: n = 25. Covariates used to estimate the propensity score: maternal age, smoking, Body mass index, gestational diabetes, hypertension disorders in pregnancy, induction of labour, epidural analgesia, occiput posterior position, prolonged pregnancy, type of instruments (forceps/ spatula delivery and vacuum delivery), small for gestational age, year of delivery and level of maternity unit

ISSN: 1471-2393