###### Q. Is a cesarean delivery indicated after a prior fourth degree laceration?

**A. Yes, a decision analysis concluded only two to three elective
cesarean deliveries would need to be performed to prevent one case of
fecal incontinence**

In the Fynes study below, 13 of 59 (22 percent) previously nulliparous
women reported altered fecal continence after their first delivery.
Eight had persistent symptoms during their second pregnancy, of whom
seven worsened following delivery. Fecal incontinence developed for the
first time in five additional women after their second delivery, three
of whom had occult sphincter injury following their first delivery.\
These and the Faltin data below suggest that women who develop altered
fecal continence or who have occult sphincter injury following vaginal
delivery are at increased risk for the development or worsening of
symptoms after a second vaginal delivery. Thus, it is reasonable to
consider cesarean birth during subsequent deliveries in women who have
sustained a tear requiring operative repair or who have developed
persistent troubling symptoms after an initial vaginal delivery (McKenna
and Wattchow below). A decision analysis concluded two to three elective
cesarean deliveries would need to be performed to prevent one case of
incontinence (Wattchow). An instrumental delivery or prolonged second
stage of labor also increases the risk of incontinence and should be
avoided whenever possible.

On the other hand, vaginal delivery itself can result in fecal
incontinence immediately or after many years. The most common injuries
are anal sphincter tears or trauma to the pudendal nerve.

There have been no large studies on women who were asymptomatic
following vaginal delivery to provide a detailed estimate of how often
anal sphincter injuries occur. Most studies focused on women in whom
there was an increased clinical suspicion for sphincter disruption thus,
probably overestimating the rate of their occurrence. A systematic
review that included five such studies with more than 100 patients who
underwent endoanal ultrasonography after vaginal delivery estimated that
anal sphincter defects were detectable in up to 27 percent of
primiparous women. (Oberwalder) However, only one-third were
symptomatic. The following are illustrative examples of studies on this
topic:

Anal sphincter tears were detected by anal endosonography in 35 percent
of primiparous and 40 percent of multiparous women of whom symptoms of
anal incontinence or fecal urgency were present in 13 and 23 percent,
respectively. (Sultan) Symptoms of urgency or incontinence usually
developed within six weeks of delivery and were more likely in women who
had forceps delivery.

**References:**

Fynes M; Donnelly V; Behan M; O\'Connell PR; O\'Herlihy C Effect of
second vaginal delivery on anorectal physiology and faecal continence: a
prospective study. Lancet 1999 Sep 18;354(9183):983-6.

<http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=10501360>

Faltin DL; Sangalli MR; Roche B; Floris L; Boulvain M; Weil A Does a
second delivery increase the risk of anal incontinence? BJOG 2001
Jul;108(7):684-8

<http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=11467691>

McKenna DS; Ester JB; Fischer JR Elective cesarean delivery for women
with a previous anal sphincter rupture. Am J Obstet Gynecol 2003
Nov;189(5):1251-6.

<http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=14634549>

Wattchow, DA et al Faecal incontinence after vaginal delivery. Lancet
1999 354:965

<http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=10501352>

Sultan AH; Kamm MA; Hudson CN; Thomas JM; Bartram CI Anal-sphincter
disruption during vaginal delivery. N Engl J Med 1993 Dec
23;329(26):1905-11.

<http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=8247054>

Oberwalder M; Connor J; Wexner SD Meta-analysis to determine the
incidence of obstetric anal sphincter damage. Br J Surg 2003
Nov;90(11):1333-7.

<http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=14598410>