A role for increased labor duration in PPH is also supported by evidence from the UK study of hemorrhage-associated peripartum hysterectomy, which showed an independent association between peripartum hysterectomy and labor of 12 hours or greater duration, adjusted for the effects of age, parity, previous CS delivery, other uterine surgery and multiple pregnancy (adjusted OR 3.04, 95%CI 1.52-6.08).
To allow for multiple pregnancy, we adjusted standard errors for clustering by mother using the Huber-White sandwich estimator, and multiplicity included as a covariate.
Because the outcomes in children from multiple pregnancies are to a certain extent non-independent, we adjusted our sample size assuming a correlation of 0.6 for composite neonatal morbidity between two children born from the same pregnancy [ 18].
34 35 Models were adjusted for potential confounders and robust variances were used to account for correlations among multiple pregnancies in the same woman.
The overall proportion of cases from multiple pregnancies which were TOPFAs was lower than singletons at every maternal age, giving an overall maternal age adjusted OR of 0.52 (95% CI 0.41 0.65; Table 4).
Clinical factors with the highest adjusted odds for severe PPH during prelabor CD were general anesthesia (adjusted odds ratio [aOR] = 22.3; 95% confidence interval [CI] = 4.9-99.9; reference group = spinal anesthesia), multiple pregnancies (aOR = 8.0; 95% CI = 4.2-15.0; reference group = singleton pregnancy), and placenta previa (aOR = 6.3; 95% CI = 3.4-11.8).
* Adjusted for occupation, referral status, mode of delivery, mode of vaginal delivery and number of gestas (singleton versus multiple pregnancies).
Models were adjusted for maternal age, child's birth year, parity, and cohort, and accounted for clustering among women with multiple pregnancies.
This association was maintained even after adjusting for relevant covariates such as the possible effect of increasing age which is often associated with multiple pregnancies [ 11, 39].
And multiple pregnancies are harder on the mom".
