Scarred Uterus: Subsequent Pregnancy and Delivery

Abstract: The aim of the work presented in this thesis was to address the problems associated with the management of pregnancy and delivery after Caesarean delivery (CD), with emphasis on ultrasound diagnostics. The prognostic value and utility of serial ultrasound examinations of Caesarean hysterotomy scars in the non-pregnant state and during pregnancy subsequent to CD were studied. This thesis includes 5 publications, and is based on 3 study populations.The first study population (Paper I) included women who had undergone repeat CD at the University Hospital in Malmö (Sweden) during the period 2005-2009. It was found that the true incidence of complete uterine rupture was higher than previously reported. The incidence of uterine dehiscence was also determined.The second study population (Papers II-IV) included women with one previous CD, recruited in a prospective cohort study at the Skåne University Hospital (Sweden). These women had undergone CD during the period from March 2013 to May 2015. The participants underwent serial ultrasound examinations in the non-pregnant state, 6-9 months after CD (transvaginal conventional ultrasound examination and saline contrast sonohysterography), and, in those who became pregnant, in the subsequent pregnancy (transvaginal and transabdominal examinations). The results presented in Paper II show that sonographic measurements of Caesarean hysterotomy scars in non-pregnant women were reliable and can be used in clinical practice. The results presented in Paper III demonstrated that the appearance of hysterotomy scars was similar in the non-pregnant state and in a subsequent pregnancy at 11-14 weeks. A cut-off value for Caesarean hysterotomy scar thickness measurement was established to predict scars with a large defect. Based on the results presented in Paper IV it was concluded that a previously published model for the prediction of successful vaginal birth after CD (VBAC), based on sonographic measurements of Caesarean hysterotomy scars, had limited utility in the Swedish population.The third study population (Paper V) included women who had trial of labour after CD at the University Hospital in Barcelona (Spain) during the period 2011-2015. The results demonstrated that the previously published model, based on maternal non-sonographic characteristics, had reasonable accuracy in the prediction of successful VBAC in women with one previous CD and singleton pregnancy.