Birth position and obstetric XXXX : a population-based study of 113 000 spontaneous births.

@entity1 @entity398 @entity1162 @entity12522 @entity130
BACKGROUND: The association between birth position and obstetric @entity130 ( @entity12522 ) in spontaneous vaginal deliveries is unclear. METHODS: The study was based on the Stockholm-Gotland Obstetric Database (Sweden) from Jan 1(st) 2008 to Oct 22(nd) 2014 and included 113 279 singleton spontaneous vaginal births with no episiotomy. We studied risk of @entity12522 with respect to the following birth positions: a) sitting, b) lithotomy, c) lateral, d) standing on knees, e) birth seat, f) supine, g) squatting, h) standing and i) all fours. All analyses were stratified for parity. General linear models were used to calculate risk ratios (RR) adjusted for maternal, pregnancy and fetal characteristics. RESULTS: The rates of @entity12522 among nulliparous @entity1 , parous @entity1 and @entity1 undergoing vaginal birth after a caesarean (VBAC) were 5.7  %, 1.3  % and 10.6  %, respectively. The rates varied by birth position: from 3.7 to 7.1  % in nulliparous @entity1 , 0.6  % to 2.6  % in parous @entity1 and 5.6  % to 18.2  % in @entity1 undergoing VBAC. Regardless of parity, the lowest rates were found among @entity1 giving birth in standing position and the highest rates among @entity1 birthing in the lithotomy position. Compared with sitting position, the lithotomy position involved an increased risk of @entity12522 among nulliparous (adjusted RR 1.17, 95  % CI 1.06-1.29) and parous @entity1 (adjusted RR 1.66, 95  % CI 1.35-2.05). Birth seat and squatting position involved an increased risk of @entity12522 among parous @entity1 (adjusted RR [95  % CI] 1.36 [1.03-1.80] and 2.16 [1.15-4.07], respectively). Independent risk factors for @entity12522 were maternal age, head circumference >= 35  cm, birth weight >= 4000  g, length of gestation   >=    40  weeks, @entity1162 , non-occiput anterior presentation and @entity398 augmentation. CONCLUSIONS: Compared with sitting position, lateral position has a slightly protective effect in nulliparous @entity1 whilst an increased risk is noted among @entity1 in the lithotomy position, irrespective of parity. Squatting and birth seat position involve an increase in risk among parous @entity1 .
