Association between the Mode of Delivery and Vertical Transmission of Human Papillomavirus.

Human papillomavirus (HPV) can be vertically transmitted. Our objective was to measure the association between the mode of delivery and the detection of HPV in infants. We used data collected from pregnant women during the HERITAGE study. Self-collected vaginal samples from the first and third trimester were obtained for HPV testing. Specimens from oral, pharyngeal, conjunctival and anogenital mucosa were collected from infants 36-48 h after delivery and at 3 months of age. All samples were tested for HPV DNA by the Linear Array assay. Adjusted odd ratios (aOR) and 95% confidence interval (CI) were estimated using multivariate logistic regressions. From the 282 women revealed to be HPV-positive in both the first and third trimesters, 25 infants were born HPV-positive. The overall probability of transmission was 8.9% (25/282); 3.7% (3/81) in participants with a caesarean section and 10.9% (22/201) for those who delivered vaginally. Vaginal delivery increased the risk of HPV in infants compared to caesarean (aOR: 3.63, 95%CI: 1.03-12.82). Infants born after a caesarean with ruptured membranes were not at increased risk of HPV compared to infants born after an elective caesarean section with intact membranes (aOR: 1.31, 95%CI: 0.10-17.76). Our results support the hypothesis that transmission occurs mostly during the passage in the vaginal canal.

Perinatal morbidity among women with a previous caesarean delivery (PRISMA trial): a cluster-randomised trial.

BACKGROUND: Women with a previous caesarean delivery face a difficult choice in their next pregnancy: planning another caesarean or attempting vaginal delivery, both of which are associated with potential maternal and perinatal complications. This trial aimed to assess whether a multifaceted intervention, which promoted person-centred decision making and best practices, would reduce the risk of major perinatal morbidity among women with one previous caesarean delivery. METHODS: We conducted an open, multicentre, cluster-randomised, controlled trial of a multifaceted 2-year intervention in 40 hospitals in Quebec among women with one previous caesarean delivery, in which hospitals were the units of randomisation and women the units of analysis. Randomisation was stratified according to level of care, using blocked randomisation. Hospitals were randomly assigned (1:1) to the intervention group (implementation of best practices and provision of tools that aimed to support decision making about mode of delivery, including an estimation of the probability of vaginal delivery and an ultrasound estimation of the risk of uterine rupture), or the control group (no intervention). The primary outcome was a composite risk of major perinatal morbidity. This trial was registered with ISRCTN, ISRCTN15346559. FINDINGS: 21 281 eligible women delivered during the study period, from April 1, 2016 to Dec 13, 2019 (10 514 in the intervention group and 10 767 in the control group). None were lost to follow-up. There was a significant reduction in the rate of major perinatal morbidity from the baseline period to the intervention period in the intervention group as compared with the control group (adjusted odds ratio [OR] for incremental change over time, 0·72 [95% CI 0·52-0·99]; p=0·042; adjusted risk difference -1·2% [95% CI -2·0 to -0·1]). Major maternal morbidity was significantly reduced in the intervention group as compared with the control group (adjusted OR 0·54 [95% CI 0·33-0·89]; p=0·016). Minor perinatal and maternal morbidity, caesarean delivery, and uterine rupture rates did not differ significantly between groups. INTERPRETATION: A multifaceted intervention supporting women in their choice of mode of delivery and promoting best practices resulted in a significant reduction in rates of major perinatal and maternal morbidity, without an increase in the rate of caesarean or uterine rupture. FUNDING: Canadian Institutes of Health Research (CIHR, MOP-142448).