Deliveries can occur either before labour, during the first stage of labour (prior to full cervical dilation), or during the second stage of labour (after full cervical dilation. In Canada, the distribution of deliveries between vaginal and cesarean delivery (CD) is well established as approximately 70% and 30% of all deliveries, respectively. However, the proportion of CDs that occur in the 2nd stage of labour has not been defined in Canada. As a result, patterns in obstetric practice related to mode of delivery in the second stage of labour are unknown, and potential shifts in these practices over time have not been assessed.
The rate of CD has increased steadily in Canada and worldwide over the last three decades due to a variety of reasons, including higher rates of advanced maternal age, comorbid conditions such as gestational diabetes, pre-existing diabetes, chronic hypertension and other chronic diseases, obesity and patient request for primary CD. Concurrent decreases in rates of operative vaginal delivery (OVD; forceps and vacuum delivery) have also been observed and often attributed to the same reasons, as well as shifts in obstetric training (fewer opportunities for training in OVD) and increased awareness of the frequency and impact of obstetric trauma following OVD. The decrease in OVDs suggests that second stage CDs are also increasing; however, population estimates of temporal trends in second stage CD are far less common and only isolated reports have shown increases in this subset of CDs. Thus, the temporal trends in second stage CD, forceps, vacuum have yet to be characterized and the impact of potential shifts in operative delivery use on maternal and perinatal morbidity rates has not been studied.
The rate of CD has increased steadily in Canada and worldwide over the last three decades due to a variety of reasons, including higher rates of advanced maternal age, comorbid conditions such as gestational diabetes, pre-existing diabetes, chronic hypertension and other chronic diseases, obesity and patient request for primary CD. Concurrent decreases in rates of operative vaginal delivery (OVD; forceps and vacuum delivery) have also been observed and often attributed to the same reasons, as well as shifts in obstetric training (fewer opportunities for training in OVD) and increased awareness of the frequency and impact of obstetric trauma following OVD. The decrease in OVDs suggests that second stage CDs are also increasing; however, population estimates of temporal trends in second stage CD are far less common and only isolated reports have shown increases in this subset of CDs. Thus, the temporal trends in second stage CD, forceps, vacuum have yet to be characterized and the impact of potential shifts in operative delivery use on maternal and perinatal morbidity rates has not been studied.