Jason Baxter | University of Portsmouth (original) (raw)
Uploads
Papers by Jason Baxter
Obstetrics & Gynecology, 2009
Background-Measurement of cervical length (CL) by transvaginal ultrasound (TVU) is predictive of ... more Background-Measurement of cervical length (CL) by transvaginal ultrasound (TVU) is predictive of preterm birth (PTB). It is unclear if this screening test is effective for prevention of PTB. Objectives-To assess the effectiveness of antenatal management based on TVU CL screening for preventing PTB. Search methods-We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (September 2008), MEDLINE (1966 to September 2008), and reviewed the reference list of all articles. We updated the search of the Cochrane Pregnancy and Childbirth Group's Trials Register on 27 January 2012 and added the results to the awaiting classification section. Selection criteria-Published and unpublished randomized controlled trials including pregnant women between the gestational ages of 14 to 32 weeks screened with TVU CL for risk of PTB. This review focuses exclusively on studies based on knowledge versus no knowledge of TVU CL results.
American Journal of Obstetrics and Gynecology, 2008
There is consensus that a placenta previa that totally or partially overlies the internal os requ... more There is consensus that a placenta previa that totally or partially overlies the internal os requires delivery by caesarean, however the mode of delivery when the placenta lies in proximity to the internal os is more controversial. Three retrospective studies concluded that a placental edge-os distance greater than 20 mm permitted a safe vaginal delivery. Conversely there is no concordance about the treatment of women with a placental edge-os distance between 0 and 20 mm. We have related transvaginal ultrasound findings with mode of delivery and outcomes in cases of complete or partial placenta previa. STUDY DESIGN: Retrospective review of 114 consecutive singleton pregnancies with placenta previa confirmed by a transvaginal ultrasound performed at Ͻ28 days of delivery. Excluded were cases with a placental-to-internal os distance of 21-30 mm (nϭ16). Cases in which the placental edge overlapped the internal cervical (nϭ42) underwent cesarean section (CS). The other cases were allowed to labor and included Group 1 (nϭ24) with a placental edge-to-internal os distance of 1-10 mm and Group 2 (nϭ29) with a distance of 11-20 mm. Likelihood of CS and other obstetric variables were compared using Chi-Square and One-Way ANOVA where appropriate. RESULTS: Mean scan-to-delivery interval was 10 days. The Group 1 and 2 differed for maternal age (35Ϯ4 vs 33Ϯ3 years, pϭ0.02) but had similar rates of nulliparity (58% vs 62%). Rates of CS (75% vs 31%, ORϭ6.7, 95% CI 2-22) and rates of bleeding before labor (29% vs 3%, ORϭ11.5, 95% CI 1.6-76.7) were significantly higher in Group 1 than Group 2. Blood loss at delivery (662Ϯ466 vs 510Ϯ547 mL, pϭ0.29) and rate of severe postpartum hemorrhage (21% vs 10%, OR ϭ 2.3, 95% CI 0.5-9.7) were similar in the 2 groups. CONCLUSION: Patients with marginal placenta previa and a placental edgeto-os distance Ͼ10 mm should be allowed to labor as more than two-thirds will deliver vaginally without increased risk of hemorrhage.
Obstetrics & Gynecology, 2009
Background-Measurement of cervical length (CL) by transvaginal ultrasound (TVU) is predictive of ... more Background-Measurement of cervical length (CL) by transvaginal ultrasound (TVU) is predictive of preterm birth (PTB). It is unclear if this screening test is effective for prevention of PTB. Objectives-To assess the effectiveness of antenatal management based on TVU CL screening for preventing PTB. Search methods-We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (September 2008), MEDLINE (1966 to September 2008), and reviewed the reference list of all articles. We updated the search of the Cochrane Pregnancy and Childbirth Group's Trials Register on 27 January 2012 and added the results to the awaiting classification section. Selection criteria-Published and unpublished randomized controlled trials including pregnant women between the gestational ages of 14 to 32 weeks screened with TVU CL for risk of PTB. This review focuses exclusively on studies based on knowledge versus no knowledge of TVU CL results.
American Journal of Obstetrics and Gynecology, 2008
There is consensus that a placenta previa that totally or partially overlies the internal os requ... more There is consensus that a placenta previa that totally or partially overlies the internal os requires delivery by caesarean, however the mode of delivery when the placenta lies in proximity to the internal os is more controversial. Three retrospective studies concluded that a placental edge-os distance greater than 20 mm permitted a safe vaginal delivery. Conversely there is no concordance about the treatment of women with a placental edge-os distance between 0 and 20 mm. We have related transvaginal ultrasound findings with mode of delivery and outcomes in cases of complete or partial placenta previa. STUDY DESIGN: Retrospective review of 114 consecutive singleton pregnancies with placenta previa confirmed by a transvaginal ultrasound performed at Ͻ28 days of delivery. Excluded were cases with a placental-to-internal os distance of 21-30 mm (nϭ16). Cases in which the placental edge overlapped the internal cervical (nϭ42) underwent cesarean section (CS). The other cases were allowed to labor and included Group 1 (nϭ24) with a placental edge-to-internal os distance of 1-10 mm and Group 2 (nϭ29) with a distance of 11-20 mm. Likelihood of CS and other obstetric variables were compared using Chi-Square and One-Way ANOVA where appropriate. RESULTS: Mean scan-to-delivery interval was 10 days. The Group 1 and 2 differed for maternal age (35Ϯ4 vs 33Ϯ3 years, pϭ0.02) but had similar rates of nulliparity (58% vs 62%). Rates of CS (75% vs 31%, ORϭ6.7, 95% CI 2-22) and rates of bleeding before labor (29% vs 3%, ORϭ11.5, 95% CI 1.6-76.7) were significantly higher in Group 1 than Group 2. Blood loss at delivery (662Ϯ466 vs 510Ϯ547 mL, pϭ0.29) and rate of severe postpartum hemorrhage (21% vs 10%, OR ϭ 2.3, 95% CI 0.5-9.7) were similar in the 2 groups. CONCLUSION: Patients with marginal placenta previa and a placental edgeto-os distance Ͼ10 mm should be allowed to labor as more than two-thirds will deliver vaginally without increased risk of hemorrhage.