Pelvic floor changes: consequences of pregnancy and delivery.

Abstract

Reimers et al. describe changes in pelvic organ support during pregnancy and at 1 year postpartum in a cohort of 300 nulliparous women. The findings are reassuring, with an overall low prevalence of prolapse (<10%) and demonstrable changes that largely recover by 1 year. Significant findings from this longitudinal study are the cranial shift of the middle compartment from mid- to late pregnancy and the shortening of the perineal body and genital hiatus from 6 weeks to 6 months postpartum. The shift of the cervix during pregnancy (cranial) and postpartum (caudal) represents the largest change in pelvic support regardless of mode of delivery. This study emphasises the mechanical forces taking place within the pelvic floor, and hypothesises how these dynamics may increase a woman's risk for the development of subsequent pelvic floor disorders. Stress urinary incontinence and pelvic organ prolapse are often associated with parity and, more specifically, vaginal childbirth; however, the mechanism of injury has not been completely elucidated and likely involves direct injury to pelvic floor muscles, connective tissue and neurovascular structures. Many healthcare providers focus on the immediate complications of childbirth and mode of delivery, such as maternal mortality, infection, anaesthetic complications, thromboembolic diseases, haemorrhage, hysterectomy and depression, but perhaps more attention should be paid to delayed maternal complications, such as subsequent uterine rupture and placental implantation abnormalities, which have significant neonatal implications; as well as urinary and fecal incontinence, pelvic organ prolapse, sexual dysfunction, and pelvic pain. The latter pelvic floor conditions may take decades to develop as other lifestyle factors such as increasing body mass index and smoking further contribute to the development of these disorders. Very few studies have evaluated long-term effects of pregnancy on pelvic floor disorders. The Norwegian EPINCONT study found that parity was associated with stress and mixed urinary incontinence, and that first delivery had the most significant impact (Rortveit G et al. Obstet Gynecol 2001;98: 1004–10). Similarly, Evers et al. reported a significant association between obstetric anal sphincter lacerations and anal incontinence, and its negative impact on quality of life 5–10 years after childbirth, compared with women who either delivered vaginally without anal sphincter laceration or delivered via caesarean section (Evers EC et al. Am J Obstet Gynecol 2012;207:425.e1–425 46). Robust longitudinal studies such as these two often cited publications provide valuable information on consequences of parity, sphincter laceration and mode of delivery. Reimers et al. are encouraged to continue the longitudinal evaluation on objective changes in pelvic support in this cohort of women and should incorporate subjective measures such as bother and impact on quality of life using validated tools. Long-term data on outcomes that matter to patients will provide the most valuable information for future practice and guideline development. None declared. Completed disclosure of interests form available to view online as supporting information.