Aim of study:
To evaluate the incidence of symptoms of urinary and fecal incontinence in primiparous women after instrumental delivery using a ventouse compared to spontaneous vaginal delivery.

Methods:
All primiparous women were invited to return for a follow-up appointment 6 to 24 months after delivery. For each instrumental delivery a matching control was examined. Matching criteria included the weight of the baby, type of episiotomy (no episiotomy, midline, medio-lateral) and perineal tears. Participants completed a detailed questionnaire on symptoms of urinary and fecal incontinence including the frequency of symptoms and a visual analog score (VAS) to evaluate subjective severity. Women were asked to state if symptoms had started before pregnancy, during pregnancy and after delivery. Pelvic floor muscle strength was assessed using the Oxford grading (0= nil to 5=very strong). Endoanal ultrasound was performed to detect defects of the internal and external anal sphincter. All patients with symptoms were offered to join the pelvic-floor reeducation program.

Results:
Eighty-two women were examined (42 matched pairs). In each group 9 women (21 %) had had a median episiotomy, 30 (71 %)a mediolateral and 3 (8 %) no episiotomy. None had a third degree perineal tear. Of the 42 women with vaginal-operative delivery 34 (81 %) had had epidural anesthesia compared to 18 (43 %) in the spontaneous delivery group (p<0.02, Chi-Square-Test). The second stage of labour was longer in the instrumental delivery group (mean 107 minutes, standard deviation (SD) 71 min. vs. mean 73 min., SD 48 min., p<0.01, t-test). There was no difference in pelvic floor muscle strength between the two groups (Score: 2.6, SD 1.5 vs. 2.4, SD 1.4, not significant). 19/42 (45%) of women after instrumental delivery had at least one symptom symptoms of anal incontinence compared to 18/42 (42%) after spontaneous delivery. The number and percentage of women, who stated to have symptoms of urinary incontinence is summarized in Table 1.

The number of women who were sure that symptoms had either started during pregnancy or after delivery is give in column 3 and 4 (post partum only). Table 1:

Table 2 shows the results for fecal incontinence symptoms. Severe symptoms of anal incontinence starting after birth were more frequent in women with instrumental delivery. Table 2:

Conclusion:
In this study both instrumental delivery and spontaneous normal vaginal delivery was associated with urinary and fecal incontinence symptoms. While the incidence of urinary incontinence did not differ between the two groups, severe fecal incontinence symptoms (incontinence for liquid and solid stool) were more frequent in women after operative delivery. Although it has been stated that vacuum delivery should be the instrument of choice, if instrumental delivery is necessary [1], this study highlights that anorectal morbidity is still high.

References:
[1] Int J Gynecol Obstet 1998;61:113-119