How Does Pregnancy and Birth Effect the Pelvic Floor? 

During pregnancy, there is a large amount of pressure placed on the pelvic floor muscles. Imagine the pelvis is like a trampoline; the rim being the bones of the pelvis, the springs being the ligaments and the mat being the pelvic floor muscles. The weight of the growing baby, hormonal changes and weight gain, weaken and stretch the mat and the springs, which is exacerbated further by vaginal birth. It is well known that weakness of the pelvic floor muscles (the mat) can lead to the development of poor control of the bladder and bowel (incontinence) and pelvic organ prolapse. 
Many studies have shown that Pelvic Floor Muscle Training (PFMT) can prevent and treat the symptoms that develop as a result of pregnancy and birth. In fact, PFMT is recommended as the number one treatment for prolapse and incontinence. For more information on bladder leakage see our blogs on Treating Bladder Problems to Empower Women or Let’s Talk About Vaginal Prolapse

Pelvic Floor Muscle Training (PFMT) and Vaginal Birth

There has been controversy in regards to the effect that PFMT has on labour and vaginal birth outcomes. One theory suggests that PFMT during pregnancy may negatively impact labour by making it harder for the baby to descend during the pushing stage1. This has unfortunately led some health professionals to discourage women from performing PFMT during their pregnancy, saying they don’t want the PFM to be too tight. 
A recent large, high quality study2 investigated the relationship between PFMT during pregnancy and labour and birth outcomes. It found that antenatal PFMT:
  • Reduces the duration of the first stage of labour (the time it takes for the cervix to become fully dilated).
  • Reduces the duration of the second stage of labour (pushing stage), which is important because a prolonged second stage of labour can increase the risk of developing a prolapse. 
  • Significantly reduces the rate of third and fourth degree perineal tears which is important because perineal tears increase the risk of bowel and wind incontinence. 
  • Does not increase the risk of episiotomy or need for forceps / vacuum assistance.

Additional Benefits of PFMT during pregnancy

Additionally, the study found women performing antenatal PFMT are:
62% less likely to experience urinary incontinence in late pregnancy
29% less likely to have urinary incontinence at 3-6 months postnatally
Less likely to experience pelvic organ prolapse 

How does PFMT actually work?

PFMT helps by enhancing muscle control and flexibility, which assists the downward movement of the baby’s head and therefore shortens the length of labour and causes less severe perineal tears. Antenatal PFMT not only reduces perineal trauma but may also help with perineal healing postnatally.2 PFMT enhances support of the bladder and pelvic organs and increases bladder control during exercise or when coughing and sneezing. 

How to get your PFMT right

For PFMT to be most effective, it is important to have an individualised program. Your Pelvic Floor Physiotherapist will first ensure that you have the correct technique and then provide you with a program based on the strength, co-ordination and endurance of your pelvic floor muscles (for more information see our article ‘Are You Looking After Yours?’). Your program will be progressed throughout your pregnancy and post-natally as your muscles get stronger. 
This recent research confirms what we have known for some time - not only is it safe and effective to be performing pelvic floor muscle exercises during your pregnancy to prevent prolapse and incontinence, it can also improve your birth and reduce the risk of perineal tears. It is recommended to have a 6-week postnatal review with your Pelvic Floor Physiotherapist for reassessment of your pelvic floor muscles and update your exercise program. 
1. Bo K and Nygaard IE (2020) Is physical activity good or bad for the female pelvic floor? A narrative review. Sports Medicine 50:471-484.
2. Sobhgol SS, Smith CA, Dahlen HG (2020) The effect of antenatal pelvic floor muscle exercises on labour and birth outcomes: a systematic review and meta-analysis. Int Urogynecol J, 31: 2189-2203. 
May 2022