Forty-five percent of women reports voiding disorders such as urinary incontinence (UI), which has a negative impact on quality of life. In young women, pregnancy and instrumented vaginal delivery are the main risk factors for developing UI [1]. Furthermore, in young nulliparous women, aging affects the physiology and composition of the pelvic floor muscles (PFM), which increases the prevalence of UI [2]. The three days voiding diary (VD) is an objective non-invasive diagnostic test that is highly reliable, simple and low cost, and reproduces voiding habits such as volume and timing of voiding, related subjective symptoms (frequency, urgency and incontinence) and fluid intake [3]. However, there are not enough data to describe the behavior of these voiding variables depending on parity and birth route. Therefore, this study aimed to evaluate VD parameters according to parity and vaginal birth route in the Spanish population.

This is a cross-sectional study, which included young nulliparous and uni/multiparous women aged 18 to 65 years. The sociodemographic and clinical data included in the VD were collected for three days, to describe their behavior (daily diuresis frequency ≤ 7, 24 hours diuresis frequency ≤ 8, maximum voiding volume, total amount of urine during the day, whether urine leakage exists, sensation of urgency and what activity was being performed at the time of leakage). Data were analyzed according to the existence of previous vaginal delivery. Descriptive and comparative analyses (X2-test or Fisher-test) were applied for categoric and continuous variables.

A total sample of 55 young nulliparous women and 35 uni/multiparous women were analyzed. The mean age was higher in uni/multiparous women than in nulliparous women. All voiding parameters from the VD for three days differed between nulliparous and uni/multiparous women, although no statistical significance was achieved. Thus, the high frequency of 24 hours diuresis, the presence of urine leakage, and of sense of urgency and what was being done at the time of leakage were more frequent in women who had vaginal delivery.

Voiding parameters collected in the VD could be affected by vaginal delivery, being predominant in uni/multiparous women with respect to nulliparous women. In uni/multiparous women, an affectation of the anatomy and innervation of the PFMs appears [1] which, together with age, leads to an increase in nocturnal polyuria in more than 33% of cases, causing UI. This is observed in European countries in 54.5% of the cases, as well as in Asian countries in 20% [2]. Consequently, the VD is supported in clinical practice for the diagnosis, evaluation and treatment of clinical states in which UI occurs [3].

Voiding parameters of the VD that are related to UI could be more frequent when women had vaginal delivery. The VD could be applied in Spanish women for clinical purposes.

Wang K, Xu X, Jia G, Jiang H. Risk Factors for Postpartum Stress Urinary Incontinence: a Systematic Review and Meta-analysis. Reprod Sci. 2020;27(12):2129-2145; doi: 10.1007/s43032-020-00254-y.
Khandelwal C, Kistler C. Diagnosis of urinary incontinence. Am Fam Physician. 2013;87(8):543-50.
Chapple CR. Is a voiding diary really necessary in 2014? Eur Urol. 2014;66(2):301-2; doi: 10.1016/j.eururo.2014.05.001.