Objective: Prematurity [gestational age (GA)<34w] is a relative contraindication to vacuum extraction (VE). Current data do not discriminate clearly between prematurity and low-birthweight (LBW). We aimed to evaluate the impact of non-metal vacuum cup extraction on neonatal head injuries related to birth-trauma (HI), among newborns with LBW (<2,500g). Design: A retrospective cohort. Population: 3,335 singleton pregnancies, delivered by VE from 2014 to 2019. All were >34w GA. Methods: We compared 207 (6.2%) neonates with LBW <2,500g to 3,128 (93.8%) neonates with higher BW, divided into 3 subgroups (2,500-2,999g, 3,000-3,499g, and >3,500g). Main outcome measures: HI and other neonatal complications. Results: The lowest rates of subgaleal hematoma occurred in neonates <2,500g (0.5%) and increased with every additional 500g of neonatal birthweight (3.2%, 4.4% and 7.6% in 2,500-2,999g, 3,000-3,499g, and >3,500g groups, respectively; p=0.001). Fewer cephalohematomas occurred among LBW neonates (0.5% in <2,500g) and increased with every additional 500g of birthweight (2.6%, 3.3% and 3.8% in 2,500-2,999g, 3,000-3,499g, and >3,500g groups, respectively, p=0.026). Logistic regression found increasing birthweight as a significant risk-factor for head injuries during VE, with adjusted odds ratios of 8.874, 10.624, 13.980 for 2,500-2,999g, 3,000-3,499g, and >3,500g, respectively (p=0.015). NICU hospitalization rates were highest among neonates weighing <2,500g (10.1%) compared to the other groups (2.7%, 1.7% and 3.3% in 2,500-2,999g, 3,000-3,499g, >3,500g respectively, p=0.000). Conclusions: VE of neonates weighing <2500g at 34w and beyond seems as a safe mode of delivery when indicated, with lower rates of HI, compared to neonates with higher BW. Funding: none.

Objective: To evaluate the relation between peripartum infection at first caesarean delivery to uterine dehiscence or rupture at the subsequent delivery. Design: Retrospective case-control study from March 2014 to October 2020. Setting: University-affiliated medical centre. Sample: Women with a prior caesarean delivery and proven dehiscence or uterine rupture diagnosed during their subsequent delivery. The control group included women who had a successful vaginal birth after Cesarean section without evidence of dehiscence or uterine rupture. Methods: We compared the rate of peripartum infection during the first Cesarean delivery and other relevant variables, between the two groups. We also analysed the type of infection correlated with uterine rupture or dehiscence. Main Outcome Measures: Rate of peripartum infection. Results: A total of 168 women were included, 71 with uterine rupture or dehiscence and 97 with successful vaginal birth after Cesarean section as the control group. The rate of peripartum infection at the first caesarean delivery was significantly higher in the study group compared to the control group (22.2% vs. 8.2%, p=0.013). Multivariate logistic regression analysis found that peripartum infection remained an independent risk-factor for uterine rupture at the subsequent trial of labour after Cesarean delivery (95% CI, P=0.018). We also found that endometritis had the highest correlation to uterine rupture (9.8% vs. 0%, p=0.02) Conclusion: Peripartum infection in the first caesarean delivery, may be an independent risk-factor for uterine rupture in a subsequent delivery. Compared to other infections, endometritis may pose the greatest risk for uterine rupture or dehiscence.