Maternal Body Mass Index and Anovaginal Distance in Active Phase of Term Labor

Linda Hjertberg, Eva Uustal, Sofia Pihl, Marie Blomberg, Linda Hjertberg, Eva Uustal, Sofia Pihl, Marie Blomberg

Abstract

Introduction: To evaluate if there was a difference in the anovaginal distance (AVD) measured by transperineal ultrasound between obese and normal weight women.

Material and methods: A prospective observational study including 207 primiparous women at term in first stage of labor. Transperineal ultrasound with a vaginal probe was used to measure the AVD. Maternal, pregnancy, and delivery characteristics potentially associated with perineal thickness were extracted from woman's medical records. The participants were divided into three BMI groups based on maternal weight in early pregnancy: normal weight (BMI < 25), overweight (BMI 25-29.9), and obesity (BMI ≥ 30). Obese and overweight women were compared with normal weight women regarding the AVD.

Results: The mean AVD was 24.3, 24.9, and 27.0 mm in the normal weight, overweight, and obesity group, respectively. There were no group differences in background characteristics. The AVD was significantly longer in obese women compared with normal weight women (p = 0.018).

Conclusions: The observed longer AVD in obese women might be protective of the anal sphincter complex, explaining lower rates of anal sphincter injuries in this group. Further studies are indicated to evaluate whether the length of the AVD plays a role in the risk assessment of obstetric anal sphincter injury. The trial is registered in ClinicalTrials.gov and the trial registration ID is NCT03149965.

Figures

Figure 1
Figure 1
Flowchart of the study population.
Figure 2
Figure 2
Transperineal ultrasound method to determine the anovaginal distance.
Figure 3
Figure 3
The anovaginal distance is shown from the internal sphincter mucosa to the posterior vaginal wall.

References

    1. Blomberg M. Maternal body mass index and risk of obstetric anal sphincter injury. BioMed Research International. 2014;2014 doi: 10.1155/2014/395803.395803
    1. Lindholm E. S., Altman D. Risk of obstetric anal sphincter lacerations among obese women. BJOG: An International Journal of Obstetrics & Gynaecology. 2013;120(9):1110–1115. doi: 10.1111/1471-0528.12228.
    1. Baumann P., Hammoud A. O., McNeeley S. G., DeRose E., Kudish B., Hendrix S. Factors associated with anal sphincter laceration in 40,923 primiparous women. International Urogynecology Journal. 2007;18(9):985–990. doi: 10.1007/s00192-006-0274-8.
    1. Deering S. H., Carlson N., Stitely M., Allaire A. D., Satin A. J. Perineal Body Length and Lacerations at Delivery. Obstetrics, Gynaecology and Reproductive Medicine. 2004;49(4):306–310.
    1. Geller E. J., Robinson B. L., Matthews C. A., et al. Perineal body length as a risk factor for ultrasound-diagnosed anal sphincter tear at first delivery. International Urogynecology Journal and Pelvic Floor Dysfunction. 2014;25(5):631–636. doi: 10.1007/s00192-013-2273-x.
    1. Yavagal S., De Farias T. F., Medina C. A., Takacs P. Normal vulvovaginal, perineal, and pelvic anatomy with reconstructive considerations. Seminars in Plastic Surgery. 2011;25(2):121–129. doi: 10.1055/s-0031-1281481.
    1. Farlex Partner Medical Dictionary. Perineal Body. .
    1. Singh K., Jakab M., Reid W. M. N., Berger L. A., Hoyte L. Three-dimensional magnetic resonance imaging assessment of levator ani morphologic features in different grades of prolapse. American Journal of Obstetrics & Gynecology. 2003;188(4):910–915. doi: 10.1067/mob.2003.254.
    1. Corton M. M., McIntire D. D., Twickler D. M., Atnip S., Schaffer J. I., Leveno K. J. Endoanal ultrasound for detection of sphincter defects following childbirth. International Urogynecology Journal and Pelvic Floor Dysfunction. 2013;24(4):627–635. doi: 10.1007/s00192-012-1893-x.
    1. Valsky D. V., Messing B., Petkova R., et al. Postpartum evaluation of the anal sphincter by transperineal three-dimensional ultrasound in primiparous women after vaginal delivery and following surgical repair of third-degree tears by the overlapping technique. Ultrasound in Obstetrics & Gynecology. 2007;29(2):195–204. doi: 10.1002/uog.3923.
    1. Timor-Tritsch I. E., Monteagudo A., Smilen S. W., Porges R. F., Avizova E. Simple ultrasound evaluation of the anal sphincter in female patients using a transvaginal transducer. Ultrasound in Obstetrics & Gynecology. 2005;25(2):177–183. doi: 10.1002/uog.1827.
    1. Chantarasorn V., Shek K. L., Dietz H. P. Mobility of the perineal body and anorectal junction before and after childbirth. International Urogynecology Journal. 2012;23(6):729–733. doi: 10.1007/s00192-012-1672-8.
    1. Pihl S., Uustal E., Hjertberg L., Blomberg M. Interobserver agreement in perineal ultrasound measurement of the anovaginal distance: a methodological study. International Urogynecology Journal. 2017:1–5. doi: 10.1007/s00192-017-3392-6.
    1. Zetterström J. P., Mellgren A., Madoff R. D., Kim D. G., Wong W. D. Perineal body measurement improves evaluation of anterior sphincter lesions during endoanal ultrasonography. Diseases of the Colon & Rectum. 1998;41(6):705–713. doi: 10.1007/BF02236256.
    1. Mayooran V., Deen K. I., Wijesinghe P. S., Pathmeswaran A. Endosonographic characteristics of the anal sphincter complex in primigravid Sri Lankan women. International Journal of Gynecology and Obstetrics. 2005;90(3):245–250. doi: 10.1016/j.ijgo.2005.04.008.
    1. Hokenstad E. D., El-Nashar S. A., Weaver A., Gebhart J. B., Occhino J. A. Perineal Body and Genital Hiatus in the Third Trimester and Risk of Perineal Laceration. Female Pelvic Medicine & Reconstructive Surgery. 2015;21(6):359–362. doi: 10.1097/SPV.0000000000000201.
    1. Meriwether K. V., Rogers R. G., Dunivan G. C., et al. Perineal body stretch during labor does not predict perineal laceration, postpartum incontinence, or postpartum sexual function: a cohort study. International Urogynecology Journal. 2016;27(8):1193–1200. doi: 10.1007/s00192-016-2959-y.
    1. Shobeiri S. A., Nolan T. E., Yordan-Jovet R., Echols K. T., Chesson R. R. Digital examination compared to trans-perineal ultrasound for the evaluation of anal sphincter repair. International Journal of Gynecology and Obstetrics. 2002;78(1):31–36. doi: 10.1016/S0020-7292(02)00068-1.
    1. Ozyurt S., Aksoy H., Gedikbasi A., et al. Screening occult anal sphincter injuries in primigravid women after vaginal delivery with transperineal use of vaginal probe: a prospective, randomized controlled trial. Archives of Gynecology and Obstetrics. 2015;292(4):853–859. doi: 10.1007/s00404-015-3708-z.

Source: PubMed

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