1. Advanced maternal age at first birth was associated with an increased risk of major obstetric pelvic floor trauma with vaginal delivery.
2. Forceps delivery was associated with increased likelihood of any type of trauma while vacuum delivery was associated with increased probability of anal sphincter injuries.
Evidence Rating Level: 1 (Excellent)
Study Rundown: Over the past four decades, the average age at first birth has increased in women living in major industrialized nations. Pregnancy at advanced maternal age, defined as over the age of 35 years old, is an established, independent risk factor pregnancy-associated morbidity and mortality. Risks of pregnancy-related complications such as miscarriage preeclampsia, and gestational diabetes are meaningfully higher in women over the age of 35. Some research suggests that older women are also more likely to have pelvic floor dysfunction possibly related to trauma during childbirth. However, these studies have been small, retrospective, and included mostly multiparous women, such that the main factors leading to pelvic floor injury remain unclear. Pelvic floor dysfunction, which can manifest as urinary/fecal incontinence or pelvic organ prolapse, is a major cause of morbidity, and affects roughly half of all women at some point in their life. In this study, researchers preformed a sub-analysis of a previous randomized controlled trial to investigate whether maternal age was linked to pelvic floor trauma in women having their first vaginal delivery.
Maternal age at first birth was associated with an increased risk of major obstetric pelvic floor trauma during vaginal delivery. Findings confirmed results of prior investigations whereby the highest likelihood of any type of pelvic floor trauma occurred with forceps delivery. This is the first study to look at the relationship between maternal age at first birth and obstetric trauma. The primary outcome was pelvic trauma at the time of birth, but what proportion of these women will go on to develop clinical pelvic floor disorders remains unclear. Further limitations include a predominantly (80%) Caucasian cohort. Future studies might prospectively recruit a more diverse study population and follow them longitudinally, assessing a more long-term clinically relevant outcome like fecal or flatal incontinence or advanced (> stage II) pelvic organ prolapse.
Relevant Reading: Levator Trauma After Vaginal Delivery
In-Depth [prospective cohort]: In a sub-analysis of a previous trial of a perinatal intervention, researchers examined the association between maternal age and obstetric trauma. All primiparous women with term, singleton vaginal deliveries at two tertiary hospitals received 3D/4D pelvic floor ultrasounds both antepartum and postpartum (n = 375). Major pelvic trauma assessed included levator ani muscle avulsion, hiatal over-distention to ≥25 cm2, and anal sphincter injuries. Multiple confounders, including forceps and vacuum-assisted vaginal delivery, were evaluated in multivariate logistic regression models.
The plurality (46%) of women experienced at least one form of major pelvic trauma. In multivariate models, advanced maternal age at first delivery was associated with increased risk of pelvic floor trauma whereby each year over the age of 18 was associated with an incrememental 6% increased odds of pelvic floor trauma (OR: 1.064 per year, p < 0.01). Forceps delivery was associated with an increased probability of all types of pelvic floor trauma while vacuum delivery was associated with greater odds of anal sphincter injuries. The trial intervention was not associated with pelvic floor trauma and was neither an effect modifier nor confounder of the relationship between age and pelvic floor trauma.
©2015 2 Minute Medicine, Inc. All rights reserved. No works may be reproduced without expressed written consent from 2 Minute Medicine, Inc. Inquire about licensing here. No article should be construed as medical advice and is not intended as such by the authors or by 2 Minute Medicine, Inc.