Pelvic Floor Disorders After Vaginal Effect of Episiotomy, Perineal Laceration, and Operative Birth

Victoria L. Handa, MD, MHS, Joan L. Blomquist, MD, Kelly C. McDermott, BS, Sarah Friedman, MD, and Alvaro Mun˜oz, PhD

OBJECTIVE: To investigate whether episiotomy, perineal who experienced at least one forceps birth (compared laceration, and operative delivery are associated with with delivering all her children by spontaneous vaginal pelvic floor disorders after vaginal . birth). METHODS: This is a planned analysis of data for a cohort CONCLUSION: Forceps deliveries and perineal lacera- study of pelvic floor disorders. Participants who had tions, but not episiotomies, were associated with pelvic experienced at least one vaginal birth were recruited floor disorders 5–10 years after a first delivery. 5–10 years after delivery of their first child. Obstetric (Obstet Gynecol 2012;119:233–9) exposures were classified by review of hospital records. DOI: 10.1097/AOG.0b013e318240df4f At enrollment, pelvic floor outcomes, including stress LEVEL OF EVIDENCE: II incontinence, overactive bladder, anal incontinence, and prolapse symptoms were assessed with a validated ques- tionnaire. Pelvic organ support was assessed using the mong parous women, cesarean birth reduces the 1 Pelvic Organ Prolapse Quantification system. Logistic Aodds of pelvic floor disorders later in life. How- regression analysis was used to estimate the relative odds ever, most U.S women deliver vaginally. Therefore, it of each pelvic floor disorder by obstetric history, adjust- is important to identify labor interventions that in- ing for relevant confounders. crease the risk of pelvic floor disorders after vaginal RESULTS: Of 449 participants, 71 (16%) had stress incon- childbirth. tinence, 45 (10%) had overactive bladder, 56 (12%) had One area of substantial controversy is the role of anal incontinence, 19 (4%) had prolapse symptoms, and episiotomy and spontaneous perineal laceration. Al- 64 (14%) had prolapse to or beyond the hymen on most 80 years ago, episiotomy was proposed as a examination. Forceps delivery increased the odds of each strategy to prevent spontaneous laceration and to pelvic floor disorder considered, especially overactive thereby reduce “pelvic relaxation.”2 Specifically, su- bladder (odds ratio [OR] 2.92, 95% confidence interval perior pelvic organ support was observed 6 weeks [CI] 1.44–5.93), and prolapse (OR 1.95, 95% CI 1.03–3.70). postpartum among women who had received episiot- Episiotomy was not associated with any of these pelvic omy.2–4 However, more recent studies have suggested floor disorders. In contrast, women with a history of that episiotomy may increase the odds of pelvic floor more than one spontaneous perineal laceration were disorders.5–7 Thus, the role of episiotomy is uncertain. significantly more likely to have prolapse to or beyond A 2005 systematic review concluded that the effect of the hymen (OR 2.34, 95% CI 1.13–4.86). Our multivari- episiotomy on the development of pelvic floor disor- able results suggest that one additional woman would 8 have development of prolapse for every eight women ders remains unknown. Also controversial is the association between op- erative delivery and pelvic floor disorders. Although From the Department Gynecology and , Johns Hopkins School of Medicine, the Department of Obstetrics and Gynecology, Greater Baltimore some research has suggested that operative delivery Medical Center, and the Department of Epidemiology, Johns Hopkins Bloomberg substantially increases the odds for pelvic floor disor- School of Public Health, Baltimore, Maryland. ders,1 other research suggests that operative birth is Supported by the Eunice Kennedy Shriver National Institute of Child Health not a strong predictor of urinary incontinence9–14 or and Human Development (R01HD056275). pelvic organ prolapse (POP).7 Corresponding author: Victoria L. Handa, MD, MHS, 4940 Eastern Avenue, 301 Building, Baltimore, MD 21224; e-mail: [email protected]. In this research, we investigated putative risk factors for pelvic floor disorders 5–10 years after © 2012 by The American College of Obstetricians and Gynecologists. Published by Lippincott Williams & Wilkins. childbirth among women who had at least one vagi- ISSN: 0029-7844/12 nal birth. This was a planned secondary aim of the

VOL. 119, NO. 2, PART 1, FEBRUARY 2012 OBSTETRICS & GYNECOLOGY 233 Mothers’ Outcomes After Delivery study, a longitu- delivery) was classified as prolonged if more than 2 dinal cohort study of pelvic floor disorders after hours. Macrosomia was defined as neonatal birth childbirth. In this analysis, we focused on whether weight of 4,000 g or more. Although all participants operative delivery, episiotomy, and spontaneous per- had their first delivery at our institution, some partic- ineal laceration were associated with the later devel- ipants delivered a subsequent child at a different opment of pelvic floor disorders among vaginally hospital. For these deliveries, we relied on the wom- parous women. Our goal was to identify modifiable an’s reported description of all obstetric events. obstetric risk factors for pelvic floor disorders. In addition to obstetric exposures, we considered the confounders of race, parity, maternal age at the MATERIALS AND METHODS time of first delivery, and obesity. Race and parity The Mothers’ Outcomes after Delivery study is a were self-reported at study enrollment. Obesity was prospective cohort study of pelvic floor outcomes in also determined at study enrollment. Specifically, women recruited 5–10 years after delivery of their each participant’s weight and height were measured first child.1 Institutional Review Board approval was and body mass index was calculated (weight (kg)/ obtained from Johns Hopkins Medicine Institutional [height (m)]2). Obesity was defined as a body mass Reviewer Board and the Greater Baltimore Medical index of 30 or more. Center Review Board, and all participants provided The outcomes of interest were the presence or written informed consent. Recruitment of women into absence of pelvic floor disorders, evaluated at the the study began in 2008 and is ongoing. The recruit- enrollment visit. We used the Epidemiology of Pro- ment methods have been described in detail else- lapse and Incontinence Questionnaire, a validated where.1 To be eligible, women must have given birth self-administered questionnaire,15 to identify women to their first child at Greater Baltimore Medical with bothersome symptoms of pelvic floor disorders. Center 5–10 years before enrollment. Participants This questionnaire generates scores for four pelvic were identified from obstetric hospital discharge re- floor disorders: stress urinary incontinence, overac- cords. To verify eligibility and to confirm delivery tive bladder, anal incontinence, and POP. In each type, each hospital chart was reviewed by a member case, a validated threshold is used to define women of our research team who was also an obstetrician. who meet criteria for the disorder. Scores greater than Obstetric exposures were derived from abstrac- these threshold values have been shown to corre- tion of all delivery records for each participant. The spond to clinically significant bother from pelvic floor exposures of primary interest were forceps and vac- symptoms.15 We used the published thresholds to uum delivery, episiotomy, and spontaneous perineal distinguish women with and without each pelvic floor laceration. These were classified after chart abstrac- disorder. tion. If relevant data were missing from the medical In addition to the research questionnaire, a gyne- record, then the participant’s recall was used to cologic examination was performed to assess pelvic classify her birth. With respect to laceration and organ support using the Pelvic Organ Prolapse Quan- episiotomy, we considered the following as mutually tification examination system.16 The examination was exclusive at the delivery level: intact ; epi- performed by physicians and a research nurse, each siotomy (with or without extension to grade 3–4); and of whom demonstrated competency in performing grade 1–2 spontaneous perineal laceration (with or the research examination before the study; compe- without extension to grade 3–4). A delivery without tency was reconfirmed throughout the study. At the an episiotomy or laceration was classified as intact time of each examination, the clinician was blinded to perineum. Midline and mediolateral episiotomies the woman’s delivery history and her symptoms. were considered as a single group because only 8% of Women were classified as having objective evidence episiotomies in this population were classified as of POP if the most dependent point of the vaginal wall mediolateral. Although these perineal exposures (epi- or the came to or beyond the hymen.1,17,18 siotomy, laceration, or intact) were defined in mutu- At enrollment into our cohort study, participants ally exclusive categories at each delivery, they were were asked about previous treatment for pelvic floor combined for each woman across all her deliveries for disorders, including surgery and pelvic muscle exer- analysis. cises (if the program was professionally supervised). Additional obstetric data were also abstracted Participants were also asked about current therapy, from the obstetric chart, including the duration of the including medications for urinary incontinence or second stage and the birth weight. The duration of the current pessary use for treatment of prolapse. Women second stage (the time from complete dilation to who reported previous surgery, previous supervised

234 Handa et al Pelvic Floor Disorders After Vaginal Birth OBSTETRICS & GYNECOLOGY pelvic muscle exercises, or any current therapy for a operative deliveries (49 had delivery by vacuum specific pelvic floor disorder were considered to have extraction, 71 by forceps, and 5 had experienced both that condition, regardless of current symptoms. vacuum and forceps). Two hundred seventy-three Contingency tables were used to estimate univari- women (61%) had experienced at least one episiot- able associations between each exposure of interest omy and 256 women (57%) experienced at least one and possible confounders, and then with each pelvic spontaneous perineal laceration. Sixty-eight women floor disorder. The P values were obtained using a (15%) experienced more than one episiotomy and 88 Fisher exact test. Next, logistic regression models women (20%) experienced more than one spontane- were used to estimate the relative odds of each ous perineal laceration. Only 14 women (3%) deliv- specific pelvic floor disorder, given a woman’s history ered without any lacerations or episiotomies across all of forceps or vacuum delivery, episiotomy, and spon- deliveries. Ninety-four women (21%) had a history of taneous perineal laceration. In these analyses, each of both episiotomy and spontaneous perineal laceration. the five pelvic floor disorders of interest (stress urinary Anal sphincter laceration was experienced by 96 incontinence, overactive bladder, anal incontinence, women (21%). This outcome was significantly associ- POP symptoms, and POP by examination) was con- ated with a history of operative delivery (42% com- sidered separately. The logistic models were adjusted pared with 13%; PϽ.001) and episiotomy (29% com- for relevant confounders, as determined in univari- pared with 9%; PϽ.001). able analyses. In the models estimating the relative As shown in Table 1, women with a history of at odds associated with episiotomy, the reference group least one spontaneous perineal laceration were more was no episiotomy (regardless of a history of sponta- neous perineal laceration in another delivery) and Table 1. Frequency of Operative Birth, there were two comparison groups, one episiotomy Episiotomy, and Spontaneous Perineal and more than one episiotomy. A similar approach Laceration Among 449 Vaginally Parous was taken with respect to modeling the relative odds Women associated with spontaneous perineal lacerations. For all analyses, PՅ.050 was considered statistically sig- Operative Spontaneous Birth* Episiotomy* Laceration* ,256؍n) ,273؍n) ,125؍nificant. (n 28%) 61%) 57%) RESULTS ϭ ϭ ϭ This study focused on 451 participants who had at African American P .324 P .365 P .766 No (nϭ398) 114 (29) 245 (62) 228 (57) least one vaginal birth and who had completed the Yes (nϭ51) 11 (22) 28 (55) 28 (55) enrollment assessment at the time of this analysis. The Aged older than Pϭ.637 Pϭ.448 Pϭ.004 451 participants reported a total of 820 vaginal 35yat and 86 cesarean delivery births. In total, medical first birth ϭ record documentation was not sufficient to classify No (n 327) 89 (27) 195 (60) 200 (61) Yes (nϭ122) 36 (30) 78 (64) 56 (46) 100 deliveries (12%) with respect to at least one of the Multiparous† Pϭ.274 Pϭ.315 PϽ.001 exposures of interest (episiotomy, laceration, or oper- No (nϭ112) 36 (32) 73 (65) 37 (33) ative delivery), including 56 deliveries that occurred Yes (nϭ337) 89 (26) 200 (59) 219 (65) at other hospitals. In those cases, maternal recall of Body mass index Pϭ.121 Pϭ.301 Pϭ.898 2 delivery events was used to classify these exposures. 30 kg/m or higher† However, even including maternal recall, two women No (nϭ375) 110 (29) 232 (62) 213 (57) could not be classified with respect to the exposures of Yes (nϭ74) 15 (20) 41 (55) 43 (58) interest, and these two women therefore were ex- Macrosomia* Pϭ.453 Pϭ.784 Pϭ.785 cluded, leaving 449 women for this analysis. Never (nϭ385) 110 (29) 233 (61) 218 (57) ϭ At enrollment, the median age was 40 years Ever (n 64) 15 (23) 40 (63) 38 (59) Second stage of PϽ.001 Pϭ.004 Pϭ.006 (range 22.7–54.4), 51 (11%) were African American, labor longer and 122 (27%) had their first delivery after age 35 than 2 h* years. Also, 337 (75%) were multiparous and 74 (16%) Never (nϭ322) 62 (19) 182 (57) 197 (61) were classified as obese. The median interval between Ever (nϭ127) 63 (50) 91 (72) 59 (46) first delivery and enrollment was 7.5 years (range Data are n (%) unless otherwise specified. 5.1–11.0). * Ever-present across all deliveries before enrollment. Operative birth, episiotomy, and laceration are not mutually exclusive. Of 449 participants, 125 (28%) had a history of at † Measured at the time of enrollment (5–10 years after first least one operative delivery and six women had two delivery).

VOL. 119, NO. 2, PART 1, FEBRUARY 2012 Handa et al Pelvic Floor Disorders After Vaginal Birth 235 Table 2. Frequencies of Pelvic Floor Disorders at Enrollment* Among 449 Vaginally Parous Women Stress Pelvic Organ Pelvic Organ Urinary Overactive Anal Prolapse Prolapse on Incontinence Bladder Incontinence Symptoms Examination (%14 ,64؍n) (%4 ,19؍n) (%12 ,56؍n) (%10 ,45؍n) (%16 ,71؍n)

Pϭ.250 Pϭ.056 Pϭ.065 006.؍Operative birth† Pϭ.239 P Never (nϭ324) 47 (14) 24 (7) 37 (11) 10 (3) 43 (13) Vacuum only (nϭ49) 7 (14) 6 (12) 5 (10) 2 (4) 4 (8) Forceps (nϭ76) 17 (22) 15 (20) 14 (18) 7 (9) 17 (22) Episiotomy† Pϭ.470 Pϭ.718 Pϭ.925 Pϭ.249 Pϭ.999 Never (nϭ176) 32 (18) 17 (10) 21 (12) 8 (5) 25 (14) One (nϭ205) 31 (15) 23 (11) 27 (13) 6 (3) 29 (14) Two or more (nϭ68) 8 (12) 5 (7) 8 (12) 5 (7) 10 (15) 021.؍Pϭ.560 Pϭ.750 P 036.؍Spontaneous laceration† Pϭ.901 P Never (nϭ193) 32 (17) 25 (13) 28 (15) 8 (4) 22 (11) One (nϭ168) 25 (15) 17 (10) 19 (11) 6 (4) 21 (13) Two or more (nϭ88) 14 (16) 3 (3) 9 (10) 5 (6) 21 (24) Data are n (%) unless otherwise specified. Prolapse on examination indicates prolapse to or beyond the hymen on physical examination. * Measured at the time of enrollment (5–10 years after first delivery). † Ever-present across all deliveries before enrollment. likely to be multiparous (PϽ.001) and were more investigated in multivariable models (Table 3). For likely to have been younger than 35 years at the time women with a history of at least one forceps delivery, of first birth (Pϭ.004). Women with a history of the relative odds of overactive bladder were increased prolonged second stage were more likely to have a almost threefold (odds ratio [OR] 2.92, 95% confi- history of operative birth (PϽ.001) or episiotomy dence interval [CI] 1.44–5.93) and the odds of pro- (Pϭ.004). In contrast, race, obesity, and macrosomia lapse to or beyond the hymen were almost doubled were not significantly associated with any of the (OR 1.95, 95% CI 1.03–3.70). Vacuum delivery did exposures of interest. not appear to increase the odds for any pelvic floor Pelvic floor disorders in this population are sum- disorder. To put the observed effect of forceps birth marized in Table 2. Seventy-one women (16%) had into perspective, we calculated the number needed to stress incontinence, 45 (10%) had overactive bladder, harm,19 a measure of the magnitude of risk associated 56 (12%) had anal incontinence, 19 (4%) had prolapse with an exposure. Assuming a causal relationship symptoms, and 64 (14%) had prolapse to or beyond between forceps delivery and prolapse, for example, the hymen on examination. Women with at least one our multivariable results suggest that one additional forceps delivery were more likely to report each of the woman would have development of prolapse for pelvic floor disorders considered, although this asso- every eight women who experienced at least one ciation was statistically significant only for overactive forceps birth (compared with delivering all her chil- bladder (Pϭ.006). Episiotomy was not significantly dren by spontaneous vaginal birth). associated with any of the pelvic floor disorders As also shown in Table 3, episiotomy was not considered. In contrast, women who had experienced associated with any of the pelvic floor disorders multiple spontaneous perineal lacerations were signif- considered. Specifically, the relative odds for each icantly more likely to have prolapse to or beyond the pelvic floor disorder were similar among women with hymen (24% compared with 12% for women with 0 or a history of no episiotomies, one episiotomy, or 1 laceration; Pϭ.021) and were significantly less likely multiple episiotomies. In contrast, the relative odds of to have overactive bladder (3% for women with two prolapse to or beyond the hymen was doubled for lacerations compared with 12% for women with 0 or women with two or more spontaneous lacerations 1 laceration; Pϭ.036). compared with women zero or one laceration (OR Because of the small number of women with 2.34, 95% CI 1.13–4.86). Because this finding was bothersome symptoms of prolapse (nϭ19), this out- relevant only for multiparous women (eg, multiple come was not considered further. For the remaining spontaneous perineal lacerations could be experi- disorders, the effect of operative delivery, episiotomy, enced only by women with multiple vaginal births), and spontaneous perineal laceration were further we performed an additional analysis of this associa-

236 Handa et al Pelvic Floor Disorders After Vaginal Birth OBSTETRICS & GYNECOLOGY Table 3. Unadjusted and Adjusted Relative Odds of Pelvic Floor Disorders (With 95% Confidence Intervals) for History of Operative Delivery, Episiotomy, and Spontaneous Laceration Among 449 Vaginally Multiparous Women Stress Urinary Overactive Anal Pelvic Organ Prolapse Incontinence Bladder Incontinence on Examination

Operative birth* Vacuum Unadjusted 0.98 (0.42–2.32) 1.74 (0.68–4.51) 0.88 (0.33–2.36) 0.58 (0.20–1.70) Adjusted† 0.99 (0.42–2.34) 1.76 (0.68–4.57) 0.90 (0.34–2.43) 0.61 (0.21–1.78) Forceps Unadjusted 1.70 (0.91–3.16) 3.07 (1.53–6.20) 1.75 (0.89–3.44) 1.88 (1.01–3.53) Adjusted† 1.65 (0.88–3.08) 2.92 (1.44–5.93) 1.66 (0.84–3.28) 1.95 (1.03–3.70) Episiotomy‡ One Unadjusted 0.80 (0.47–1.38) 1.18 (0.61–2.29) 1.12 (0.61–2.06) 1.00 (0.56–1.77) Adjusted§ 0.71 (0.41–1.25) 0.90 (0.45–1.81) 0.98 (0.52–1.85) 1.01 (0.55–1.84) More than two Unadjusted 0.60 (0.26–1.38) 0.74 (0.26–2.10) 0.98 (0.41–2.34) 1.04 (0.47–2.30) Adjusted* 0.57 (0.24–1.35) 0.67 (0.23–2.01) 1.01 (0.41–2.48) 0.87 (0.38–1.98) Spontaneous laceration‡ One Unadjusted 0.88 (0.50–1.56) 0.76 (0.39–1.46) 0.75 (0.40–1.40) 1.11 (0.59–2.10) Adjusted† 0.96 (0.54–1.73) 0.87 (0.44–1.72) 0.84 (0.44–1.60) 1.16 (0.60–2.24) More than two Unadjusted 0.95 (0.48–1.89) 0.24 (0.07–0.81) 0.67 (0.30–1.49) 2.44 (1.26–4.72) Adjusted* 1.14 (0.54–2.39) 0.33 (0.10–1.18) 0.80 (0.34–1.90) 2.34 (1.13–4.86)

Pelvic organ prolapse on examination indicates, prolapse to or beyond the hymen on physical examination. * Models were performed with two indicator variables. Vacuum indicates a history of at least one vacuum delivery but no forceps birth. Forceps indicates a history of forceps with or without a history of vacuum delivery. † Odds ratios are adjusted for maternal age older than 35 years at first delivery and multiparity at enrollment. ‡ Models were performed with two indicator variables, one for one episiotomy or laceration and one for two or more episiotomies or lacerations. § Odds ratios are adjusted for maternal age older than 35 years at first delivery, multiparity at enrollment, and history of any operative delivery. tion restricted to women who had experienced at least demonstrate an association between prolapse and a two vaginal births. In this subset of 283 women, the single spontaneous perineal laceration. relative odds of prolapse remained significantly ele- The observed association between spontaneous vated among those with two or more spontaneous laceration and the later development of prolapse is perineal lacerations (OR 2.26, 95% CI 1.00–5.09). biologically plausible, given recent evidence of the role of levator ani injuries in the genesis of prolapse. DISCUSSION Magnetic resonance imaging suggests that avulsion of Our findings suggest that forceps deliveries and per- the levator from the pubis is associated with prolapse ineal lacerations (but not episiotomies) are associated later in life.20 Biomechanical models of the pelvic with pelvic floor disorders 5–10 years after a first floor predict that avulsion of the levator ani occurs delivery. Women with perineal lacerations in two or with excessive stretching of the levator hiatus during more deliveries were at significantly higher risk for crowning of the fetal head.21 We speculate that spon- prolapse. In contrast, even among women with mul- taneous perineal laceration may be a marker of tiple episiotomies across multiple , the excessive stretch at the time of delivery. odds for incontinence and prolapse were not elevated. Episiotomy was relatively common in this popu- Our data do not suggest a “dose–response” relation- lation: 61% of vaginally parous women experienced ship between perineal laceration and prolapse. Spe- an episiotomy during at least one birth. In contempo- cifically, the increase in prolapse was statistically rary obstetric practice, episiotomy is performed dur- significant only in women with at least two lacera- ing 25–35% of U.S. deliveries.8,22,23 Thus, our partici- tions. It is unclear whether this represents a threshold pants’ episiotomy rates may be higher than those of effect or whether a larger study would be required to other centers. An argument in favor of restricted use

VOL. 119, NO. 2, PART 1, FEBRUARY 2012 Handa et al Pelvic Floor Disorders After Vaginal Birth 237 of episiotomy is the prevention of anal sphincter evidence of prolapse. The importance of these objec- lacerations,23,24 theoretically reducing anal inconti- tive anatomic data is highlighted by the relatively low nence.25 However, despite the association between prevalence of prolapse symptoms in this cohort. episiotomy and anal sphincter laceration among our Research based only on symptoms might not capture participants, we did not find an association between some of the associations observed in this research. episiotomy and anal incontinence. Ideally, our find- Although these data demonstrate a significant ings should be replicated in a low-episiotomy setting increase in the odds of prolapse among women who to investigate whether a more restrictive use of epi- have experienced forceps birth or multiple perineal siotomy would yield different findings. lacerations, the “big picture” is that the differences Another important finding from this research is between vaginal birth and cesarean delivery birth1 are that forceps delivery increased the odds of pelvic floor more notable than the differences identified among disorders 5–10 years after first delivery. The increase those who deliver vaginally. The mechanisms respon- was statistically significant only for overactive bladder sible for the incidence of pelvic floor disorders after and prolapse. Given the relatively low prevalence of vaginal childbirth may not yet be recognized and the pelvic floor disorders in this population, we had most “risky” aspects of vaginal childbirth may not be limited power to exclude an association between measured and recorded during routine obstetric care. forceps birth and either stress urinary incontinence or Our findings argue for further investigation of the anal incontinence. With longitudinal follow-up of this mechanisms underlying the critical links between cohort, we will have an opportunity to investigate childbirth and pelvic floor function later in life. whether continence and pelvic organ support deteri- orate more in some groups than others. We consid- ered only the first 5–10 years after childbirth, and this REFERENCES interval may not be sufficient to see the effect of some 1. Handa VL, Blomquist JL, Knoepp LR, Hoskey KA, McDer- mott KC, Mun˜ oz A. 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