title: Perineal Distensibility Using Epi-no in Twin Pregnancies: Comparative Study with Singleton Pregnancies.
abstract: The aims of this study were to compare perineal distensibility between women with twin and singleton pregnancies and to correlate these women's perineal distensibility with anthropometric data. This prospective cross-sectional case-control study was conducted among nulliparous women, of whom 20 were pregnant with twins and 23 with a single fetus. Perineal distensibility was evaluated in the third trimester by means of Epi-no, which was introduced into the vagina and inflated up to the maximum tolerable limit. It was then withdrawn while inflated and its circumference was measured. The unpaired Student's t-test was used to compare perineal distensibility in the two groups and Pearson's correlation coefficient (r) was used to correlate the pregnant women's perineal distensibility with their anthropometric data. There was no difference in perineal distensibility between the twin group (16.51 ± 2.05 cm) and singleton group (16.13 ± 1.67 cm) (P = 0.50). There was a positive correlation between perineal distensibility and abdominal circumference (r = 0.36; P = 0.01). The greater the abdominal circumference was, the greater the perineal distensibility was, regardless of whether the pregnancy was twin or singleton.
authors.affiliation: Pelvic Floor Sector, Department of Obstetrics, Federal University of São Paulo (UNIFESP), Rua Carlos Weber, 956 Apartment 113 Visage, Vila Leopoldina, 05303-000 São Paulo, SP, Brazil.
authors.forename: Juliana Sayuri
authors.initials: JS
authors.lastname: Kubotani
authors.affiliation: Pelvic Floor Sector, Department of Obstetrics, Federal University of São Paulo (UNIFESP), Rua Carlos Weber, 956 Apartment 113 Visage, Vila Leopoldina, 05303-000 São Paulo, SP, Brazil.
authors.forename: Antonio Fernandes
authors.initials: AF
authors.lastname: Moron
authors.affiliation: Pelvic Floor Sector, Department of Obstetrics, Federal University of São Paulo (UNIFESP), Rua Carlos Weber, 956 Apartment 113 Visage, Vila Leopoldina, 05303-000 São Paulo, SP, Brazil.
authors.forename: Edward
authors.identifier: 0000-0002-6145-2532
authors.initials: E
authors.lastname: Araujo Júnior
authors.affiliation: Pelvic Floor Sector, Department of Obstetrics, Federal University of São Paulo (UNIFESP), Rua Carlos Weber, 956 Apartment 113 Visage, Vila Leopoldina, 05303-000 São Paulo, SP, Brazil.
authors.forename: Miriam Raquel Diniz
authors.initials: MR
authors.lastname: Zanetti
authors.affiliation: Pelvic Floor Sector, Department of Obstetrics, Federal University of São Paulo (UNIFESP), Rua Carlos Weber, 956 Apartment 113 Visage, Vila Leopoldina, 05303-000 São Paulo, SP, Brazil.
authors.forename: Vanessa Cardoso Marques
authors.initials: VC
authors.lastname: Soares
authors.affiliation: Pelvic Floor Sector, Department of Obstetrics, Federal University of São Paulo (UNIFESP), Rua Carlos Weber, 956 Apartment 113 Visage, Vila Leopoldina, 05303-000 São Paulo, SP, Brazil.
authors.forename: Julio
authors.initials: J
authors.lastname: Elito Júnior