Obstetric Myths Versus Research Realities
Chapter 14: Episiotomy
The Downside of Episiotomies
Pain and Dyspareunia
Factors That Reduce the Probability of Tears
The Downside of Episiotomies
Note: As you read this, consider that the most common way doctors describe episiotomy to women is as a "little cut," which implies episiotomy is a trivial matter.
19. Varner MW. Episiotomy: techniques and indications. Clin Obstet Gynecol 1986;29(2):309-317. (both, but I confine the abstract to midline)
This clinical practice paper discusses how to perform and repair both types of episiotomies. [Indications that Varner lists that are not supported by the literature include "prolonged second stage of labor" and "premature infant," as indications distinct from "fetal distress," the potential problem with prematurity or long pushing phase. He also lists "prevention of maternal lacerations." The illogic of lacerating the perineum in order to protect it from laceration needs no further comment from me.]
- "Caution must be observed in both techniques that the rectum is not entered inadvertently."
- "If it is performed too early, excess blood loss will probably occur."
- "The sutures should be placed tightly enough to ensure hemostasis, but not so tightly as to occlude capillary perfusion." [The episiotomy should be stitched tightly enough to prevent bleeding but loosely enough for blood flow in the tissue.]
- "If the knot is placed at or inside the hymenal ring, postpartum dyspareunia can be minimized."
- "[P]ostpartum discomfort or dyspareunia can be minimized by avoiding suture knots at the fourchette [the fold connecting the two inner labia (labia minora) at the base of the vulva]."
- "A gentle rectal examination should be performed to ascertain that no sutures were inadvertently placed through the rectal mucosa. Such sutures could serve as a nidus of infection or fistula formation."
- "A sponge and needle count should also be routinely performed at the conclusion of the repair. Besides being embarrassing, a sponge retained in the vagina may be the nidus for an infection. Likewise, a needle retained or broken off in the episiotomy repair mandates exploration of the wound."
- "Perineal extensions of midline episiotomies frequently involve the rectal sphincter or mucosa." "[In repairing a third-degree extension] the importance of attention to anatomic reapproximation and hemostasis as well as the use of interrupted sutures cannot be overemphasized for successful repair."
- "Successful repair of . . . vaginal extensions can challenge the most experienced surgeon."
- "Severe hemorrhage is possible with episiotomy." "Excessive perineal pain should raise the possibility of a perineal, vulvar, vaginal, or ischiorectal hematoma [a blood-filled swelling]."
- "As with any surgical procedure, infection is a potential complication of episiotomy. . . . A rare but extremely serious and sometimes fatal infectious complication of episiotomy is necrotizing fasciitis."
- "Many patients receiving episiotomies require oral analgesics for several days afterward."
- "Most patients with postepisiotomy pain gradually recover over the ensuing several months."
- "Postepisiotomy pain that is catamenial [synchronized to the menstrual cycle] in nature may represent endometriosis [within the episiotomy scar]."
- "Another aspect of episiotomy pain that should not be underestimated is its psychosexual impact."
- "Relative contraindications" include the "patient's absolute refusal to consent to the procedure."
Pain and Dyspareunia
20. Abraham S et al. Recovery after childbirth: a preliminary prospective study. Med J Aust 1990;152(1):9-12. (both)
Primiparas who gave birth vaginally (N = 93) were studied to evaluate factors influencing perineal pain. In 62% an episiotomy was performed. Women having spontaneous births (67%) "predominantly" had midline episiotomies. Those with forceps deliveries mostly had mediolateral episiotomies. Sixteen percent had an episiotomy and an extension or vaginal tear, of which one involved the anus. Of those who had no episiotomy, 31% did not require stitches. One tear involved the anus.
At one month postpartum, 41% reported perineal pain, 12% at two months, 7% at three months, 2% at four months, and 0% by six months. Pain during intercourse was reported by 91% at one month, 59% at two months, 33% at three months, 18% at four months, and 15% at five months. A gradual decrease followed until at one year 1% reported dyspareunia. The median time for perineal comfort was one month and three months for comfortable sexual intercourse. [The authors did not adjust for breastfeeding, a confounding factor for dyspareunia because low estrogen levels can cause vaginal dryness.] Of 20 women who reported no discomfort the first few days, 13 were using pain-relief methods. [Their evaluation may reflect only the effectiveness of those methods.] Factors associated with longer than average perineal pain or dyspareunia were a vaginal but not perineal tear; forceps delivery [forceps may cause vaginal tears or bruising]; and mediolateral rather than midline episiotomy [but women with mediolateral episiotomies were also the women with forceps]. Women who had spontaneous births with episiotomy had similar outcomes compared with women without episiotomy. Performing an episiotomy did not prevent vaginal tears.
Note: Episiotomy predisposes to rectal tears. 21. Snooks SJ et al. Risk factors in childbirth causing damage to the pelvic floor innervation. Br J Surg 1985;72(Suppl):S 15-S 17. (unstated but presumably mediolateral because this is a British study)
The effect of childbirth on the pudendal nerve and the external anal sphincter was studied in 62 primiparas and 60 multiparas. Twenty women (16%) had elective cesareans. Results were compared with 34 nulliparous controls. Most women (90%) who had an elective epidural had forceps deliveries. Vaginal birth in and of itself, adversely affected these measurements as did forceps use in primiparas, bigger babies, and longer second stage [but women with bigger babies and/or longer second stages would be more likely to have forceps deliveries]. Episiotomies and tears were equivalent, providing the tear did not involve the anal sphincter. In these cases, injury was not more than that due to vaginal birth. Third-degree tears, on the other hand, showed evidence of greater long-term injury. The authors believe that women who still had evidence of nerve damage to the pelvic floor musculature two months after delivery were at greater risk for anal incontinence later in life, especially, since damage is cumulative, if they went on to have more children. Two multiparas, neither with a third-degree tear, experienced fecal soiling postpartum.
22. Haadem K et al. Anal sphincter function after delivery rupture. Obstet Gynecol 1987;70(1):53-56.
Of 63 women who had partial or total tears of the anal sphincter, 59 (95%) responded to a questionnaire sent two to seven years later. Two women had postoperative infections: one developed a rectovaginal fistula, the other a necrosis and rerupture of the sphincter. Both required further surgery. Despite prompt surgical repair, 28 (45%) reported symptoms: 19 of incontinence "especially for gas," five of dyspareunia, and four of perineal pain. Women with problems were offered an evaluation of anal sphincter function, and 14 accepted. The reference group was 10 women of similar age and parity who had no sphincter rupture or anal disease.
The women with anal sphincter injury showed reduced muscle strength compared with controls. Since reduced strength had persisted for years, it should be considered permanent. Slight impairment does not necessarily result in incontinence, but the margin between continence and incontinence is reduced. Since anal sphincter strength decreases with age, women with sphincter injuries are at increased risk for incontinence later in life. [Testing was not offered to women who were symptom free, but it would be interesting to know how strength would compare in these women. If they had weaker anal sphincters, they could be headed for trouble down the line.]
Factors That Reduce the Probability of Tears
23. Avery MD and Van Arsdale L. Perineal massage: effect on the incidence of episiotomy and laceration in a nulliparous population. J Nurse Midwifery 1987;32(3):181-184.
Perineal outcomes were compared between 29 nulliparous women who practiced perineal massage and 26 similar control women. Women in the massage group were instructed to massage the vaginal opening 5 to 10 minutes daily with a natural vegetable oil beginning at 34 weeks. They were to massage the oil into the perineum and lower vaginal wall. Then they, or their partner, were to massage using a "U" or "sling" movement, stretching enough to produce a slight burning sensation. Pelvic floor contractions [Kegels] were also recommended.
In the massage group, 52% had an intact perineum or first-degree laceration, and 48% had an episiotomy and/or second-degree or deeper tears. Among controls, 24% had an intact perineum or first-degree laceration and 76% had an episiotomy and/or second-degree or deeper tears (P < 0.05). The episiotomy rate was 38% in the massage group versus 65% among controls. All third-degree tears were preceded by episiotomy. [Keep in mind that the study was not blinded and births were mostly attended by midwives with a commitment to avoiding episiotomy.]
24. Thompson DJ. No episiotomy?! Aust N Z J Obstet Gynaecol 1987;27(1):18-20.
This clinical practice paper recommends that as the birth commences, support the perineum, keep the fetal head flexed, have the mother push gently or pant, gently push the anterior vagina over the back of the baby's head, wait until the mother pushes the anterior shoulder into view, and deliver the shoulders one at a time. By proceeding in this fashion, distension of the perineum and risk of injury are minimized. Comparing 100 consecutive deliveries in 1985 using this technique to 100 deliveries in 1983, the episiotomy rate was 7% versus 78% and the incidence of intact perineum was 68% versus 16%. All episiotomies accompanied forceps deliveries, but 55% of forceps deliveries were over an intact perineum. The majority of tears were first degree; there were three second-degree tears and no third-degree tears.
25. Nodine PM and Roberts J. Factors associated with perineal outcome during childbirth. J Nurse Midwifery 1987 May-June;32(3):123-130.
Perineal outcomes of 275 spontaneous vaginal births of term occiput anterior infants were examined. The episiotomy rate was 34.2%, of which 4.4% had extensions. Overall 17.8% had intact perineums; 19% had spontaneous first-degree tears; 15.8% had second-degree tears; and 12.8% had periurethral or labial tears. No one had a spontaneous third- or fourth-degree tear. Factors associated with episiotomy were use of analgesia (P < 0.001) and maternal position for birth (P < 0.001). In particular, women with no analgesia had the highest rate of intact perineums (34.1%), and women with epidurals had the highest episiotomy rate (65.2%). Episiotomy rates by birth position were: 14% semisitting; 20% dorsal [supine with legs flexed but not in stirrups]; Sims 33.3% [side lying]; and 55.3% lithotomy [supine, legs in stirrups]. Intact perineum rates by position were: 31.6% semisitting, 17.5% Sims, 15% dorsal, and 12.8% lithotomy. (Too few women squatted to provide data.) Women who gave birth in the dorsal position were most likely to have a spontaneous second-degree tear. However, relationships are complex. For example, the lithotomy position is more likely to be used when an episiotomy is anticipated. First-time mothers were more likely to have an episiotomy, but the association disappeared when birth position was factored in because they were more likely to give birth in the lithotomy position. Attendant's experience may also be a factor. Maternal position is related to perineal outcome only when student midwives attend the birth. More research is needed.
26. Legino LJ et al. Third- and fourth-degree perineal tears. 50 years' experience at a university hospital. J Reprod Med 1988;33(5):423-426. (midline)
Currently 82% of all women at this U.S. hospital have episiotomies. Since 1980 the percentage of third-degree tears and fourth-degree tears has been stable at 10.7% and 6.4%, respectively. Between 1982 and 1985 all women with third- and fourth-degree tears (N = 743) were compared with women without such tears (N = 3,893). The following associated with deep tears: nulliparity (82% versus 38%, P < 0.0001), use of oxytocin (47% versus 29%, P < 0.0001), epidural anesthesia (22% versus 7%, P < 0.01), and forceps delivery (34% versus 7%, P < 0.0001). Residents had higher deep tear rates than staff doctors (P < 0.001) (experience counts). Two or more predisposing factors were present in 91% of cases and three or more in 51%. [This is not surprising; for example, a woman with an epidural is likely to have oxytocin and forceps.] A big baby (> than or = to 4000 g) was not associated with a greater risk of tear, probably because such babies are likely to be cesarean deliveries.
27. Borgatta L, Piening SL, and Cohen WR. Association of episiotomy and delivery position with deep perineal laceration during spontaneous delivery in nulliparous women. Am J Obstet Gynecol 1989;160(2):294-297. (midline)
The study group was 241 nulliparous women having spontaneous, vertex, singleton births. The episiotomy rate was 46.1%. Midwives attended 65.1% of births and obstetricians the rest. Doctors were more likely to use stirrups (P < 0.01). Of the 174 women known to give birth in an alternative position, the most common was semisitting (N = 153). Apgar scores did not relate to episiotomy.
"Deep lacerations" (third or fourth degree) were fewest (0.9%) in women without episiotomy who were not in the lithotomy position and highest (27.9%) in women with both. Women with one factor but not the other had intermediate rates. Episiotomy correlated strongly with deep tears (OR 22.46 CI 7.81-64.61, P < 0.003) as did the lithotomy position (OR 14.01 CI 4.18-47.28, P < 0.029). The role played by birth attendant is unclear. Doctors had a higher tear rate, but they were more likely to do episiotomies and to use stirrups. This may reflect that they would be called in when there were problems. When data are adjusted for stirrups and episiotomy, the association between doctor and deep tears disappeared. [Still, doctors are more likely to do episiotomies and use the lithotomy position regardless of labor complications.] One possible explanation for the relationship between stirrups and deep tears is that the position overstretches the perineum.
28. Helwig JT, Thorp JM, and Bowes WA. Does midline episiotomy increase the risk of third- and fourth- degree lacerations in operative vaginal deliveries? Obstet Gynecol 1993;82(2):276-279. (midline)
The records of all instrumental deliveries were examined (N = 392) to determine the relationship between episiotomy and third- and fourth-degree lacerations. Sixty percent of instrumental deliveries were performed without an episiotomy. After adjusting for birth weight and primiparity, episiotomy more than doubled the risk of a deep tear during instrumental delivery (RR 2.4 CI 1.7-3.5). For primiparas, the deep tear rate for episiotomy versus no episiotomy was 48.5% versus 20.3% and the rates for intact perineum or lesser tears were 51.5% versus 79.7%. Similarly, for multiparas, the deep tear rates were 21.4% versus 8.7%, and the rates for intact perineum or lesser tears were 78.6% versus 91.3%.