gms | German Medical Science

Background: In Germany, the prevalence of out-of-hospital births is fairly stable at 1.6%. In contrast to that, the rate of caesarean sections has been rising (33% in 2011). This means that an increasing number of women who commenced their delivery in an out-of-hospital setting have a caesarean section in their medical history. However, a vaginal birth after a previous caesarean section (VBAC) in an out-of-hospital setting is discussed controversially. The question is posed whether there is a difference between the risks in pregnant women who previously had a previous caesarean section and women who previously had a vaginal delivery? Is there a selection according to potential risk factors by the midwives in the out-of-hospital setting in response of the previous mode of birth?

Method: A secondary analysis of German perinatal out-of-hospital data of the years 2005 to 2011 was done. 66,437 women with a singleton pregnancy in a cephalic presentation at term who started delivery in an out-of-hospital were included. There were 25,000 primiparae and 41,437 second- and multipara. Of the total number, 2,217 women had a previous caesarean section. Out of 56 potential risk factors in pregnancy which are listed in the perinatal documentation sheet, the ten most frequently documented risks were chosen to be compared between the three groups.

Results: No significant differences were found in women who had a previous serious illness, haemorrhage, skeletal abnormalities, or anaemia. Women with a prior caesarean section were older (p<0.05), had more often two or more miscarriages, or abortions, and were more obese than primiparae (p<0.05). There were more allergies in women with a previous caesarean section than in women with a previous vaginal delivery (p<0.05). Diverse uterine surgeries were found most often in the group who had a previous caesarean section. The risk of short spacing between pregnancies was mostly documented concerning women with a previous vaginal birth.

Discussion: Of the ten selected potential risks in pregnant women, seven showed no significant differences between women with a previous caesarean section and women with a prior vaginal birth. Two potential risks were documented mostly in the group of women who had a caesarean section as their last mode of birth. From this analysis, no selection according to potential risk factors can be identified.

Recommendations: The examined potential risk factors in this analysis might be a reason for the rise in complications during birth. In this case, we should discuss including and excluding criteria for the out-of-hospital deliveries for women with a previous caesarean section. The distance to the next clinic as an important risk factor must be considered. In this context it is also imperative to counsel women with a previous caesarean section regarding the possible risks and benefits of a vaginal birth in an out-of-hospital setting.