OBJECTIVE: To investigate the effect of pregnancy and delivery on anal cont
inence, sensation, manometry, and sphincter integrity.
STUDY DESIGN: Two hundred eighty-six nulliparous women in the third trimest
er completed a symptom questionnaire and underwent anorectal sensation and
manometric evaluations. Three months postpartum, 161 women returned and the
questionnaires and investigations were repeated together with anal endoson
ographic examinations.
RESULTS: The prevalence of fecal urgency before, during, and after pregnanc
y was 1%, 9.4%, and 10.5%, respectively; the prevalence of anal incontinenc
e before, during, and after pregnancy was 1.4%, 7.0%, and 8.7%, respectivel
y. Vaginal delivery, particularly instrumental, resulted in a decrease In a
nal squeeze pressures (P = .015) and resting pressures (P = .002) but had n
o effect on anal sensation. Postpartum anal endosonographic examination rev
ealed sphincter disruption in 38% of women. There was no relationship betwe
en symptoms and anal manometry, sensation, or sphincter integrity. Vaginal
delivery (P < .0001) and perineal trauma (P < .001) were significantly asso
ciated with sphincter defects.
CONCLUSION: Vaginal delivery is associated with a decrease in anal pressure
s and increased anal sphincter trauma but has no effect on anal sensation.
These changes were not related to anal symptoms.