[Impact of twin gestation on the risk of postpartum stress incontinence]

Effect of gestational weight gain on postpartum pelvic floor function in twin primiparas: a single-center retrospective study in China

BACKGROUND

The effect of gestational weight gain (GWG) as a controllable factor during pregnancy pelvic floor function has rarely been investigated, and studies on twin primiparas are even less frequent. The objective of the present study was to explore the effect of GWG on postpartum pelvic floor function in twin primiparas.

METHODS

We retrospectively analyzed the clinical data of 184 twin primiparas in the pelvic floor rehabilitation system of the First Affiliated Hospital of Chongqing Medical University from January 2020 to October 2021. Based on the GWG criteria recommended by the Institute of Medicine, the study subjects were classified into two groups: adequate GWG and excessive GWG. Univariate and multivariate logistic regression models were applied to explore the relationship between GWG and pelvic floor function.

RESULTS

Among the 184 twin primiparas, 20 (10.87%) had excessive GWG. The rates of abnormal vaginal dynamic pressure (95% vs. 74.39%), injured type I muscle fibers (80% vs. 45.73%), anterior vaginal wall prolapse (90% vs. 68.90%), and stress urinary incontinence (50% vs. 20.12%) of twin primiparas with excessive GWG were significantly higher than those with adequate GWG. There was no significant difference between the total score of the Pelvic Floor Distress Inventory-Short Form 20 (PFDI-20) or the scores of the Pelvic Organ Prolapse Distress Inventory 6 (POPDI-6), the Colorectal-Anal Distress Inventory 8 (CRADI-8), and the Urinary Distress Inventory 6 (UDI-6) in the two groups (P > 0.05). After adjusting for potential confounding factors, the results showed that excessive GWG was positively associated with abnormal vaginal dynamic pressure (OR = 8.038, 95% CI: 1.001-64.514), injured type I muscle fibers (OR = 8.654, 95% CI: 2.462-30.416), anterior vaginal wall prolapse (OR = 4.705, 95% CI: 1.004-22.054), and stress urinary incontinence (OR = 4.424, 95% CI: 1.578-12.403).

CONCLUSION

Excessive GWG in twin primiparas was positively correlated with the prevalence of pelvic floor dysfunction but did not exacerbate pelvic floor symptoms in twin primiparas. Controlling GWG within a reasonable range is recommended for reducing the risk of PFDs in pregnant women with twins.

Transperineal three-dimensional ultrasound for analyzing the effects of perineal stretching with EPI-NO® in women with multiple pregnancies: a pilot study

Objective: To compare the changes in the pelvic floor of women with twin pregnancies who practiced muscle stretching with the EPI-NO^® vaginal dilator, as assessed using transperineal three-dimensional ultrasound (3DUS).Method: This prospective cross-sectional case-control study included nulliparous women in the third trimester of their multiple pregnancies and divided them into the control group (CG, n = 9) and EPI-NO^® group (EpiG, n = 9). During pretreatment, the women underwent transperineal 3DUS to establish the morphometric measurements of the pelvic floor. The CG received guidance regarding pelvic floor muscles, whereas the EpiG underwent weekly physical therapy sessions with the EPI-NO^® dilator for 20 min/day. Following this treatment, all women were reassessed using transperineal 3DUS, and the diameter of the EPI-NO^® balloons of the women in the EpiG was measured (epinometry). Paired samples t-test was used for comparative analysis.Results: The EpiG showed improved perineal distensibility, which was evidenced by the increase in sagittal diameter at rest (p < .01). Transperineal 3DUS among women in the EpiG showed a significant increase in the sagittal measurement (p = .02), hiatal circumference at rest (p = .03), and epinometry values (diameter of the EPI-NO^® balloon; p < .01). The increase in epinometry values was directly correlated (p = .02) with the number of physical therapy sessions.Conclusion: EPI-NO^® increased pelvic floor distensibility in women with twin pregnancies, as confirmed using transperineal 3DUS and epinometry. This device promoted an increase in perineal distensibility with a single use; however, better results would be obtained with additional sessions.

A comparative study of obstetric anal sphincter injuries in vaginal deliveries of twins and singleton pregnancies

AIMS

Increasing numbers of twin pregnancies necessitate investigation of the risk factors associated with obstetric anal sphincter injuries (OASIS). The aims of this study were to establish the incidence of OASIS, and compare women delivering twins to those delivering singletons in risk of OASIS plus maternal, neonatal, and obstetric outcomes.

METHODS

A retrospective cohort study was undertaken and included women delivering in a tertiary London maternity unit between 1999 and 2015; 51 957 eligible women with singleton and 261 with twin pregnancies were identified. Women delivering twins were compared to those delivering singletons in the occurrence of maternal, neonatal, and obstetric outcomes using unadjusted relative risks. A secondary analysis was performed, and conditional logistic regression used to derive an adjusted relative risk of OASIS. Women delivering singletons were matched to those delivering twins for age, parity, ethnicity, gestation, and mode of delivery in a ratio of 2:1.

RESULTS

Compared to the singleton group, mothers delivering twins had significantly more instrumental deliveries (RR [95%CI] 1.92 [1.67-2.27]; P < 0.0001), smaller fetuses (2754.1 vs 3383.8 g; P < 0.001), and were older (32.9 vs 31.0 years; P < 0.0001). The twin group was not significantly different to the singleton group in risk of OASIS (RR 0.61 [0.27-1.33], P = 0.205). The conditional logistic regression demonstrated similar results for the risk of OASIS (adjusted RR = 0.58 [0.22-1.47]; P = 0.253).

CONCLUSIONS

Women delivering twins vaginally were not at a significantly higher risk of sustaining OASIS compared to those delivering singletons.

Assessing the impact of twin pregnancies on the pelvic floor using 3-dimensional sonography: a pilot study

OBJECTIVES

The purpose of this study was to compare the morphologic characteristics of the pelvic floor musculature between women with twin and singleton pregnancies.

METHODS

We conducted a cross-sectional case-control study of 40 nulliparous women aged 20 to 38 years to compare women with singleton pregnancies (n = 23) to women with twin pregnancies (n = 17). Biometric measurements of the levator hiatus and the sagittal and coronal diameters were made by transperineal 3-dimensional sonography between the 28th and 38th gestational weeks. Comparisons were statistically assessed by the unpaired Student t test and Mann-Whitney U test.

RESULTS

For the women with singleton pregnancies, the mean sagittal diameters at rest, during the Valsalva maneuver, and during pelvic floor contraction were 5.3, 5.7, and 4.5 cm, respectively, and the mean coronal diameters under these conditions were 3.8, 4.1, and 3.6 cm. For the women with twin pregnancies, the corresponding values were as follows: mean sagittal diameters, 5.3, 5.8, and 4.6 cm; and mean coronal diameters, 4.3, 4.3, and 3.8 cm. The differences in coronal diameters were statistically significant at rest (P < .01) and during contraction (P = .04). The mean levator hiatal areas for the women with singleton pregnancies were 14.6, 16.9, and 11.7 cm(2) at rest, during Valsalva, and during contraction, respectively; for the women with twin pregnancies, these values were 16.0, 18.6, and 12.6 cm(2).

CONCLUSIONS

Hiatal measurements were higher in twin than in singleton pregnancies, with coronal diameters reaching significance at rest and during contraction, suggesting that pelvic support undergoes greater changes during twin pregnancy.

Perineal Distensibility Using Epi-no in Twin Pregnancies: Comparative Study with Singleton Pregnancies

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.

Female urinary incontinence during pregnancy and after delivery: Clinical impact and contributing factors

Urinary incontinence (UI) is a common condition affecting adult women of all ages and it could have a negative influence on quality of life. The etiology of UI is multifactorial, but some of the most important risk factors are obesity and ageing, as well as adverse obstetric events. Pregnancy and delivery per se have been implicated in the etiology of UI. Although several studies have demonstrated a direct association between UI and vaginal delivery in short, medium and long-term, the role of childbirth on the risk of UI remains controversial. The mechanical strain during delivery may induce injuries to the muscle, connective and neural structures. Vaginal birth can be associated with relaxation or disruption of fascial and ligamentous supports of pelvic organs. Parity, instrumental delivery, prolonged labor and increased birth weights have always been considered risk factors for pelvic floor injury. Also genetic factors have been recently raised up but still there are not appropriate guidelines or measures to reduce significantly the incidence of UI. The role of pelvic floor muscle training (PFMT) in the prevention and treatment of UI is still unclear. However, PFMT seems to be useful when supervised training is conducted and it could be incorporated as a routine part of women’s exercise programmes during pregnancy and after childbirth.