Introduction

The pelvic floor is a group of muscles and connective tissues that stretch across the bottom of the pelvis. These muscles provide support to the pelvic organs, control bladder and bowel functions and are important in sexual function. 

During pregnancy, the pelvic floor is under additional strain and this can increase the risk of incontinence (loss of control of bladder and/or bowel functions), pelvic organ prolapse (the slipping down of a pelvic organ from its usual position) and sexual dysfunction.¹⁵

Exercising the pelvic floor can help to keep it strong and functioning optimally. Pelvic floor strength training is important during pregnancy to avoid issues that can negatively affect one’s quality of life. 

Understanding the pelvic floor

The pelvic floor is made up of layers of several different muscles and connective tissues. These muscles are essential in several bodily functions, including:

• Continence: Through voluntary constriction and relaxation of the urethra (the tube through which urine leaves the body) and the anus (the opening through which faeces leaves the body)
• Optimal sexual function: Through constriction and relaxation of the vagina
• Support: The pelvic floor supports the organs situated in the pelvic cavity, the bladder, uterus and bowel
• Core stability: In conjunction with other core muscles, the pelvic floor muscles are important for balance, stability, force transference and to protection of the lumbar spine¹

The pelvic floor during pregnancy

During pregnancy, the pelvic floor is under increased strain due to several factors. These include:

• Increased pressure placed on the pelvic floor by the weight of the growing baby and general weight increases during pregnancy
• Softening and relaxation of the muscles and connective tissues of the joints in the pelvis to allow greater flexibility and movement of the pelvis during labour and delivery
• Production of a greater volume of urine due to several physiological changes, along with greater pressure on the bladder from the enlarged uterus, resulting in increased frequency of urination and increased sensations of urgency to urinate²
• Decrease in collagen (a protein important in maintaining muscle and connective tissue structure and strength) due to hormonal changes, which can weaken pelvic floor muscles³
• Increased straining of pelvic floor muscles due to constipation, common during the third trimester of pregnancy¹⁵

Benefits of pelvic floor exercises during pregnancy

Pelvic floor strength training during pregnancy can bring many benefits, preventing the development of uncomfortable symptoms. Pelvic floor exercises can prevent incontinence, prolapse, and sexual dysfunction whilst improving core stability.

Prevention of incontinence of bladder and bowel

Incontinence is the inability to fully control bladder and bowel functions, resulting in involuntary loss of urine, faeces or wind. It can range in severity from small leakages to full loss of control. Stress urinary incontinence is the most common form of incontinence during pregnancy.⁴ This is when small amounts of urine are involuntarily passed during physical activities such as laughing, coughing, sneezing or exercising. Bowel/faecal incontinence can also occur. 

Prevention of pelvic organ prolapse 

A pelvic organ prolapse is when the bladder, bowel or uterus slips down from its usual position, putting pressure on other structures. The bladder and bowel may slip into a position where they put pressure on the vaginal walls, causing them to bulge inwards or compress. The rectum (the final section of the bowel) can also slip down and protrude out of the anus. The uterus can slip down into the vagina or even protrude out of the vaginal opening. 

This movement of organs can occur due to the loss of support of connective tissues (tissue that provides a framework to bind and support organs and other structures of the body), and/or loss of strength of pelvic floor muscles. 

Organ prolapse is a rare occurrence during pregnancy. Maintaining a strong and healthy pelvic floor can help minimise this risk.

Prevention of sexual dysfunction

Sexual function is complex and multifactorial. Pelvic floor function is believed to be a contributing factor through several different mechanisms. Weak pelvic floor strength can result in a reduction in sex drive and arousal, infrequent orgasm or sexual pain/discomfort.⁵ 

There is still a lack of evidence regarding the effect of pelvic floor muscles on sexual function specifically during pregnancy, and research in this area is ongoing.⁶

Improvement of core stability

Pelvic floor muscles work in conjunction with other core muscles to provide core stability, helping to improve balance and protect the lumbar spine. Pelvic and lumbar spine joints are particularly vulnerable to injury during pregnancy due to hormonally-induced relaxation of ligaments, the increase in weight being carried and shifts in the centre of gravity.¹⁶ Maintenance of good core stability is therefore important during this period to reduce the risk of back and pelvic pain.

How to strengthen pelvic floor muscles

Studies have shown that pelvic floor dysfunction can be reduced by pelvic floor muscle training to increase strength.^{7, 8} This can be done before and during pregnancy, and continued after birth. NHS Scotland recommends doing pelvic floor exercises every day, incorporating them into your daily routine.

Pelvic floor exercise instructions

Pelvic floor exercises are simple for most people and can usually be performed on your own without any equipment. These involve engaging the pelvic floor muscles and consciously contracting and then releasing them. Combining quick hold and long hold contractions is recommended.

The Women’s Hospital, Australia, gives the following instructions for performing these exercises:

Starting position: Exercises can be carried out whilst sitting, standing, lying on your back or on all fours. It is recommended that a variety of different positions be used.

Long hold exercises:

1. Tighten muscles around the anus, vagina and urethra, pulling inwards and upwards, as though trying to stop yourself from passing wind or urinating
2. Contract these muscles and hold for 3-5 seconds, then release
3. Repeat up to 10 times or until you are unable to continue effectively due to muscle fatigue, resting for a few seconds between each contraction

Quick hold exercises:

1. Contract pelvic floor muscles as above as quickly and strongly as possible, then immediately release
2. Repeat 10-20 times with a few seconds pause between each contraction

Repeat these quick and long hold exercises three times each per day.

Breathing should remain normal throughout these exercises. Buttock, abdomen and thigh muscles should stay relaxed. 

The NHS has an information video on pregnancy and pelvic floor strength available here.

Trained professionals such as Women’s Health Practitioners, Physiotherapists and Specialist Nurses can advise how to identify and activate these muscles. These specialists can be consulted if you are having difficulty initiating or implementing these exercises on your own. 

Biofeedback can also be used to give objective measures of muscle contraction.^3,10 This involves the use of a sensor device inserted into the rectum or vagina which measures muscle activity and provides objective readings. This feedback can help improve awareness and allow active control of muscle contraction to be gained. This can be helpful when initiating pelvic floor exercises and to show progress.

These exercises are sometimes referred to as ‘Kegel exercises’ or ‘Kegels’, after the American Gynaecologist, Arnold Kegel, who first introduced them in the 1940s.⁹

Establishing a pelvic floor exercise strengthening routine

The optimal frequency and duration of exercises to help in strengthening the pelvic floor during pregnancy is not agreed upon, and will depend on many factors, including pelvic floor strength pre-pregnancy. However, in general, it is recommended that exercises are carried out several times a day, every day, throughout pregnancy and continued after the birth. The Mayo Clinic recommends 3 sets of 10-15 repetitions each day. 

In addition, it is often recommended that the pelvic floor is engaged and contracted during activities which put them under increased pressure such as laughing, coughing, sneezing, lifting or exercising. 

As well as being beneficial during pregnancy, establishing a pelvic floor exercise regime ante-natally (prior to the birth) can make it easier to continue postnatally (after the birth). The immediate postnatal period can be a busy time when accessing services to gain the necessary information and establishing new routines may be harder.¹¹

Pelvic floor exercises are an important component of overall pregnancy fitness and well-being. Further information from the NHS on safe exercises during pregnancy can be found here.

The importance of continuing pelvic floor exercises post-natally

Pelvic floor muscles and associated soft tissues can be damaged during labour and vaginal birth.³ Childbirth injuries can include muscle stretching and tears and perineal (area between the vagina and anus) tears or cuts (episiotomies). There can also be damage to nerves in this area.¹² The risk is increased with assisted deliveries, such as forceps or vacuums.¹³

Pelvic floor exercises are an important part of postpartum recovery. They can be resumed soon after birth and should be incorporated into daily life on an ongoing basis. Restoring the strength and regaining control of these muscles can help reduce incontinence, prevent pelvic organ prolapse, and restore optimal sexual function. 

Risk factors for pelvic floor dysfunction during pregnancy

All pregnancies put the pelvic floor under increased strain, but certain factors further increase the risk of developing pelvic floor dysfunction. These include:

• Maternal age over 30
• Previous pregnancies
• Previous assisted deliveries
• Occiput posterior foetal position (when the back of the baby’s head is at the back of the mother’s pelvis, also known as ‘face up’ or ‘back to back’)
• Previous birth involves a long second stage of labour (the stage between full dilation of the cervix and birth of the baby)
• Obesity
• Chronic constipation
• Chronic cough
• Smoking
• Lack of exercise
• Diabetes
• Family history
• Pre-existing symptoms of pelvic floor dysfunction¹¹

FAQs:

When should you start doing pelvic floor exercises during pregnancy?

It is recommended that all people assigned female at birth (AFAB) carry out pelvic floor exercises regularly. The Royal Women’s Hospital, Victoria, Australia, recommends that all people AFAB exercise their pelvic floor muscles every day throughout their lives. This should continue throughout pregnancy and after the birth. If you have not already established a pelvic floor exercise routine before pregnancy, this can be started as soon as you know that you are pregnant. 

What are the symptoms of a weak pelvic floor during pregnancy?

Weak pelvic floor muscles can increase the risk of incontinence during pregnancy, particularly stress urinary incontinence, when small amounts of urine are lost involuntarily during physical activities such as laughing, coughing, sneezing or lifting. Weakness in these muscles can also increase the risk of pelvic organ prolapse and reduce sexual function. 

How common are complications from weak pelvic floor muscles during pregnancy?

According to the Cochrane organisation, more than one-third of people experience urinary incontinence, and one-quarter experience bowel (faecal) or flatus (wind) incontinence during pregnancy. 

Pelvic organ prolapse is uncommon during pregnancy, with only 1 case in every 10,000 - 15,000 individuals.¹⁴

Summary

The pelvic floor is the layers of muscles and connective tissues which form the base of the pelvic cavity, providing support to the pelvic organs, controlling bladder and bowel functions, and playing a role in sexual function. During pregnancy, these muscles are under increased strain. Urinary stress incontinence, in particular, is a very common symptom during pregnancy and following childbirth.

Strength training exercises can help to restore function and control of pelvic floor muscles and reduce the risk of developing incontinence and other issues. It is recommended that they are incorporated into prenatal fitness routines to ensure optimal pelvic health during pregnancy.