Spina Bifida – A Guide

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Spina bifida is a term that is used to refer to a series of birth defects that affect the development of the spine and nervous system.

Symptoms of spina bifida
Causes of spina bifida
Diagnosing spina bifida
Treating spina bifida
Complications of spina bifida
Preventing spina bifida


The neural tube

During the first month of life, an embryo grows in a primitive tissue structure called the neural tube. As the embryo develops, the neural tube begins to change into a more complicated structure of bones, tissue and nerves that will eventually form the spine and nervous system.

In cases of spinal bifida, something goes wrong with the development of the neural tube, and the spinal column (the ridge of bone that surrounds and protects the nerves) does notfully close. Spina bifida is a Latin term that means ‘split spine’.

Types of spina bifida

There are three main types of spina bifida:

  • Spina bifida occulta.
  • Spina bifida meningocele.
  • Myelomeningocele.

Spina bifida occulta

Spina bifida occulta is the most common (and least serious) type of spina bifida. In spina bifida occulta, the opening in the spine is very small, with a tiny gap between one or more vertebrae. Vertebrae are the disc-shaped bones that make up your spine.

Spina bifida occulta usually causes no symptoms, and most people will remain unaware that they have the condition. In such cases, no treatment is required.

Spina bifida meningocele

Spina bifida meningocele is the rarest type of spina bifida. In this type of spina bifida, the bones of the spine develop normally, but the protective membranes are pushed out between openings in the vertebrae. These membranes can usually be removed during surgery, and no further treatment is required.

As the nervous system remains undamaged, a person who is born with spina bifida meningocele is unlikely to experience any long-term health problems.


Myelomeningocele is the most serious type of spina bifida. It occurs in an estimated one in every 1,000 births.

In cases of myelomeningocele, the spinal column remains open along several vertebrae, and the membranes and spinal cord push out to create a sac in the baby’s back. The sac can be covered with skin, but it often remains open, leaving the nervous system vulnerable to infections that may be fatal.

In some cases of myelomeningocele, the spinal column can be repaired using surgery. However, extensive damage to the nervous system will have usually taken place already. Damage can result in a range of symptoms including:

  • Partial or total paralysis of the lower limbs.
  • Learning difficulties.
  • Bowel and bladder incontinence.

Around 70% of children with myelomeningocele will also develop hydrocephalus, a condition where there is excess cerebrospinal fluid (CSF). CSF is the fluid that surrounds the brain.

The build-up of CSF is caused by problems with the development of the neural tube. Hydrocephalus needs to be treated with surgery because the extra pressure that is placed on the brain by the fluid can cause brain damage.


Advancements in the treatment of spina bifida have resulted in a considerably improved prognosis for the condition.

Before the 1970s, most children with spina bifida would die in their first year of life. But today, an estimated 80% of children survive into adulthood. Although spina bifida can be a challenging condition to live with, many adults with spina bifida lead independent and fulfilling lives.

The rest of this article focuses on myelomeningocele, and this is the type of spina bifida that will be referred to whenever the term ‘spinal bifida’ is used.

Symptoms of spina bifida

The severity of the symptoms of spina bifida usually depends on two factors:

  • where on the spine the opening occurs, and
  • whether the baby also develops hydrocephalus (excess fluid on the brain).

Children who experience an opening at the top of their spine are more likely to experience total paralysis of their lower limbs and other mobility difficulties than children who experience an opening in the middle or base of their spine.

Children who also develop hydrocephalus are more likely to have learning difficulties than children who do not.

Types of symptoms

Spina bifida can cause a wide range of symptoms, which can be grouped into three general categories. The categories are:

  • Cognitive symptoms, such as difficulties reading or problem solving.
  • Mobility symptoms, such as paralysis and muscle weakness.
  • Bladder and bowel symptoms, such as urinary and bowel incontinence.

Cognitive symptoms

The defects that occur in the neural tube also affect the development of the brain. Abnormal brain development is known as a Type 2 Arnold-Chiari malformation.

The cerebellum is the main area of the brain that is affected. The cerebellum is the part of the brain that is thought to be responsible for important cognitive functions, such as language processing, concentration and physical co-ordination.

Further brain damage can occur if hydrocephalus places excess pressure on the brain.

Most children with spina bifida have below-average intelligence, although not severely below average. In the general population, the average IQ (which stands for intelligence quotient and is a measurement of intelligence) is 100. Most people with spina bifida have an average IQ of 80.

By definition, an average measurement of IQ will never properly represent the full range of IQ levels, and there are many children with spina bifida who have above-average intelligence.

Children with spina bifida may have some specific learning difficulties. These include:

  • a short attention span,
  • difficulties with problem solving,
  • reading difficulties,
  • difficulties understanding some spoken language, particularly complicated language or rapid conversations between a group of people,
  • difficulties organising activities or making detailed plans,
  • difficulties understanding abstract concepts, such as logic or cause and effect, and
  • difficulties with visual and physical co-ordination, for example, tasks such as tying shoelaces or fastening buttons.

Mobility symptoms

The brain controls all of the muscles in the body with the nerves that run through the spinal cord. Any damage to the nerves can result in problems controlling the muscles.

Most children with spina bifida will experience some degree of paralysis in their lower limbs. If a child with spina bifida is partially paralysed, they may need to use leg braces or canes to help with walking. In cases where a child is totally paralysed, they will require a wheelchair.

Paralysis can also cause other, associated problems. For example, as the muscles in the legs are not being regularly used, they can become severely weakened. As the muscles support the bones, this weakness can affect bone development, resulting in:

  • dislocated joints,
  • misshapen bones, and
  • abnormal curvature of the spine (scoliosis).

Bowel and bladder symptoms

As well as controlling your limbs, the nerves that run through your spinal column also control your bowel and bladder. Specifically, they help to control the muscles of the sphinctersthat are found both in the bladder and bowel.

These sphincters act as gates.They contract to keep urine and stools (faeces) in, and relax to let urine and stools out. Most people with spina bifida have limited, or no, control over their sphincter muscles. Because of thisthey experience urinary and bowel incontinence.

Urinary incontinence can take the form of a constant slow dribble of urine from the bladder.

If a child has bowel incontinence, they may experience periods of constipation because they are unable to use their sphincter muscles to push stools out of their bowel. This can then be followed by episodes of diarrhoea or soiling due to stools overflowing from the bowel.

Causes of spina bifida

The causes of spina bifida are unknown, although most experts agree that the condition is probably caused by a combination of environmental and genetic factors. A number of risk factors for spina bifida have been identified, which are described below.

Folic acid

The most significant risk factor for spina bifida is having an insufficient intake of folic acid during pregnancy. Folic acid is a vitamin that occurs naturally in some foods, such as leafy vegetables, granary bread and some breakfast cereals. Folic acid tablets are also available form pharmacies, supermarkets and health stores.

Women with a very low intake of folic acid are eight times more likely to give birth to a baby with spina bifida compared with women who take the recommended amount.

Exactly how folic acid helps prevent spina bifida is still uncertain. One theory is that it regulates the formation of genetic material that later proves important in an embryo’s development.

See the Prevention section for more information and advice about folic acid and folic acid supplements.

Previous pregnancy

If you have previously had a child with spina bifida, there is a slightly higher chance that any other children you have will also have the condition. The risk ranges from 3-8%.


Two types of medicine (valproic acid and carbamazepine) have been linked to an increased risk of spina bifida. These medicines are both used to treat epilepsy and some mood disorders, such as bipolar disorder and schizophrenia.

The associated risks of valproic acid and carbamazepine are outlined below.

  • Carbamazepine has about a 2% risk of causing spina bifida.
  • Sodium valproate, when taken at a daily dose of less than 1,000mg, has about a 5% chance of causing spina bifida.
  • Sodium valproate, when taken at a daily dose of more than 1,000mg, has about a 9% chance of causing spina bifida.
  • If carbamazepine and sodium valproate are taken together, there is a risk of just under 9% of spina bifida occurring.

Due to this increased risk, it is recommended that sexually active women who are taking these medicines should always use contraception.

If you are taking valproic acid and/or carbamazepine, and you are planning a pregnancy, speak to your treatment team because alternative medications may be available. Taking folic acid supplements can also help minimise the risk.


Women with diabetes have an increased risk of giving birth to a child with spina bifida. This may be due to the excess amount of glucose in the blood interfering with the child’s development.

The level of risk will depend on the severity of your diabetes. However, it is thought that women with diabetes are between two and eighttimes more likely to have a child with spina bifida compared with women who do not have diabetes.


Women who are obese have an increased risk of giving birth to a child with spina bifida. The more obese you are, the higher the risk. Severely obese women (with a body mass index (BMI) that is greater than 40) are thought to be three times more likely to give birth to a child with spina bifida than women who are a healthy weight.

Diagnosing spina bifida

Most cases of spina bifida are detected during routine blood tests carried out during an antenatal screening appointment.

Alpha fetoprotein

If your baby has spina bifida, you will have an increased level of a protein known as alpha fetoprotein (AFP) in your blood.

However, a high level of AFP in your blood does not always mean that your baby has spina bifida. Further tests will be required to confirm this.

Ultrasound and amniocentesis

The first test that you have will be an ultrasound scan. It may be able to detect problems with your baby’s spine that could indicate the presence of spina bifida.

Another test is amniocentesis. During amniocentesis, a needle is used to draw out a sample of amniotic fluid, which is the fluid that surrounds and supports the foetus. A high level of AFP in the amniotic fluid is often an indicator of spina bifida.

An ultrasound scan is an entirely safe procedure. However, there is a 1% chance that amniocentesis could cause a miscarriage.

Treating spina bifida

Your care team

If your child is diagnosed with spina bifida, both they and you will be introduced to a team of health professionals who will be involved with helping you to look after your child.

The care team may include:

  • a paediatrician (a specialist in the treatment of children),
  • a neurologist (a specialist in treating conditions that affect the nervous system),
  • a urologist (a specialist in treating conditions that affect the urinary system),
  • a health visitor,
  • a social worker,
  • a physiotherapist (a therapist who can help to improve range of movement and co-ordination),
  • an occupational therapist (a therapist who can help to improve the skills and abilities that are needed for daily activities, such as washing or dressing,
  • an incontinence adviser, and
  • an educational psychologist (a psychologist who specialises in helping people with learning difficulties).

An individual care plan will be drawn up to address any needs or problems that your child has. As your child gets older, the plan will be continually reassessed to accommodate changes to their needs and situation.

You and your child will also be assigned a keyworker, who will be the first point of contact between yourself and the various support services that are available. While your child is young, the keyworker is likely to be a health visitor. However, as your child gets older and their needs become more complex, it is likely that the keyworker will be a social worker.

Surgery to repair the spine

If your child has spina bifida, surgery to repair their spine will normally take place within 48 hours of their birth. During surgery, the surgeon will place the spinal cord and any exposed tissues or nerves back into your child’s body, close any gap in the vertebrae and seal the spinal cord with muscle and skin.

There have been cases where surgery is performed when a baby is still in the womb (pre-natal surgery). However, at present, there is not enough evidence to say whether pre-natal surgery is more effective and clinically safer than post-natal surgery.

A large medical trial is currently underway in the US to determine which type of surgery is most effective. The results of the trial should be available in a few years time.

Treating hydrocephalus

If your child has hydrocephalus (excess fluid on the brain), the surgeon will install a shunt during surgery. A shunt is a thin tube that is implanted in the brain. The shunt will drain away any excess fluid to another part of the body, usually the abdomen.

Once the shunt has been installed, your child should not require any further surgery for hydrocephalus. However, occasionally the shunt can become blocked and shunt repair surgery is required. See the Complications section for more information about shunt malfunction and shunt repair surgery.

Physical therapy

Physical therapy is one of the most important waysto helpyour child to manage their condition and gain as much independence as possible. The main aim of physical therapy for spina bifida is to prevent the child’s leg muscles from weakening.

The physiotherapist will teach your child a number of physical exercises that they can carry out every day to strengthen their leg muscles. Special leg braces may also be used to help strengthen your child’s leg muscles.

Occupational therapy

Occupational therapy is designed to improve your child’s posture, and to make the most of what mobility they already have. They will also be advised about the best way for them to carry out day-to-day tasks that require a degree of physical dexterity, such as going to the toilet and getting dressed.

Occupational therapy can be extremely useful for boosting your child’s self-esteem and independence.

Further orthopaedic surgery

If your child develops problems with the development of their bones, such as scoliosis or dislocated joints, further surgery may be required in order to correct this. This type of surgery is known as orthopaedic surgery.

A back brace is often used to treat the symptoms of scoliosis.

Urinary incontinence

Treating your child’s symptoms of urinary incontinence is an important way of boosting their self-esteem and helping them to develop more independence.

It is likely that you and your child will be referred to a urologist so that their bladder function can be assessed.

Some of the most widely used treatments for urinary incontinence, in cases of spina bifida, are outlined below.

Clean intermittent catherisation

Clean intermittent catherisation (CIC) is a technique used to empty the bladder at regular intervals. A catheter is a small, flexible lubricated tube. An incontinence advisor will teach you, and your child (when they are old enough) how to place the catheter through your child’s urethra and into their bladder.

Your child’s urine will flow out of their bladder, through the catheter and into the toilet. At first, using a catheter can feel a little painful, but any pain should subside over time.

How often CIC will need to be performed will depend on your child’s individual circumstances. Some children only need to perform CIC once a day, while others will need to catherise themselves betweenfour and sixtimes a day.

Regular use of a catheter increases the risk of your child developing a urinary tract infection (UTI). The symptoms of a UTI include:

  • passing foul-smelling, cloudy urine, and
  • general symptoms of an infection, such as fever and vomiting.

Contact your GP as soon as possible if you think that your child may have a UTI.

Artificial urinary sphincter

An artificial urinary sphincter (AUS) is a device that is surgically implanted in order to help treat urinary incontinence. The AUS is made up of a silicone cuff that is surrounded by fluid and a pump. The cuff is attached to the sphincter and the pump is placed under the skin of the scrotum (the sac containing the testicles) in males, or the labia (the lips of the vulva) in females.

The fluid in the cuff contracts the sphincter, keeping the urine in place. When it is time to go to the toilet, your child will press the pump. The pump temporarily empties the fluid from the cuff, releasing the pressure on the cuff. This opens the sphincter, allowing the urine to be released into a toilet. After a few minutes the fluid will return to the cuff, closing the sphincter.

AUSs are not recommended for use by boys who have not reached puberty. This is because, whenthey reach puberty,they will experience physical changes that would require the removal and reinsertion of the AUS.

Mitranoff procedure

The Mitranoff procedure is a surgical technique where the appendix is removed and one end is connected to the bladder, and the other to the wall of the abdomen in order to create a channel. If your child’s appendix has been removed, there are alternative methods of creating a Mitranoff channel.

After the Mitranoff channel has been created, a small opening is made in, or below, your chid’s naval. This opening is known as a stoma. After the procedure is complete, your child can place a catheter into the stoma to empty their bladder.

Botulinum toxin

Some children with spina bifida have a bladder condition known as hyper-reflexic bladder.

Due to problems with the nervous system, the muscles of the bladder experience abnormal contractions. The contractions can prevent the bladder from filling properly and place the urine within the bladder at an increased pressure.

The increased pressure can cause incontinence and may also push urine back into the kidneys, which can trigger a UTI.

Botulinum toxin is a powerful poison which is safe to use in minute doses. An injection of toxin is used to paralyse the muscles of the bladder. The effects of the treatment last for around six months after which a further injection will be required.

Treating bowel incontinence

Some cases of bowel incontinence can be treated using a combination of dietary and toilet training techniques.

Ensuring that your child eats a balanced diet that contains plenty of high-fibre foods should help to soften their stools, prevent constipation and make emptying their bowel easier.

Foods that are high in fibre include:

  • fruit,
  • vegetables,
  • wholegrain rice,
  • wholewheat pasta,
  • wholemeal bread,
  • seeds,
  • nuts, and
  • oats.

Some foods can make stools too soft, which could lead to episodes of diarrhoea and soiling. These foods include:

  • citrus fruit,
  • pineapple,
  • corn (both fresh and tinned),
  • chocolate, including chocolate milk,
  • nuts, and
  • dried fruit.

You should encourage your child to adopt a regular bowel-emptying routine at least once a day. After breakfast is usually a good time for emptying the bowel because this is the time when natural bowel movements are most active.

If your child has difficulty passing stools, coughing or laughing when on the toilet can sometimes encourage bowel movement. Your incontinence adviser may also teach your child massage techniques they can use to encourage bowel movements.

Further treatment may be required if these techniques do not prevent episodes of constipation, diarrhoea or soiling.


There are a number of different medicines that can be used to treat the symptoms of constipation and diarrhoea. These include laxatives, which can help to soften stools, and loperamide, which can be used to help treat diarrhoea.

Never give your child over-the-counter (OTC) anti-diarrhoea medicine because many are not suitable for children. Always consult your GP if you require help with your child’s diarrhoea.

Anal plugs

Anal plugs are a good way to prevent episodes of soiling. An anal plug is made of foam and is designed to be inserted into your child’s anus. This can feel a little strange at first, but most children become used to it.

If the plug comes into contact with any moisture from the bowel, it expands into a mushroom shape preventing any leakage or soiling. Anal plugs can be worn for up to 12 hours, after which time they are removed using an attached string.


Strapping can be used as an alternative to, or in combination with, anal plugs, in order to prevent soiling. Strapping literally involves strapping the buttocks together using a waterproof tape. Your incontinence adviser will be able to advise you how to do this correctly.


Enemas can be used to help children with spina bifida who are experiencing difficulties emptying their bowel, and who have not responded to other forms of treatment. Enemas can clean out the bowel fortwo to threedays.

A tube is inserted into the anus and a special solution is used to wash out the bowel. The contents of the bowel are collected in an attached bag so that they can be disposed of.

Your incontinence adviser may be able to train you, and your child, to perform an enema in your own home.


If your child does not respond to any of the above treatment, surgery may be required. Some commonly used surgical treatments are outlined below.

Antegrade continence enema

Antegrade continence enema (ACE) is a surgical procedure that is designed to make enemas easier and more convenient.

As with AUS, the surgeon uses the appendix to create a channel between the bowel and the abdomen. A stoma is then made in the surface of the abdomen. A catheter can then be inserted into the stoma so that liquids can be passed into the bowel in order to wash out its contents through the anus.

Colostomy and ileostomy

During a colostomy, the surgeon will surgically re-route a section of the bowel so that it connects to a stoma that is made in the abdomen. A pouch is connected to the stoma, which is used to collect the contents of the bowel.

An ileostomy is a similar procedure to a colostomy. However, in an ileostomy, it is the small intestine, rather than the colon, that is re-routed to a stoma.

Assistive technology

There is a range of different technologies that can help children with spina bifida to gain more independence and control over their symptoms.

Children with total paralysis of the lower limbs will require a wheelchair. Electric wheelchairs are available, but using a manual wheelchair can help a child with spina bifida to maintain good upper-body strength.

Leg braces and other walking aids can be used for children with only partial paralysis.

Computers are also a good tool for helping your child to overcome any learning difficulties that they may have. Software is available that can help children to organise their activities and plan their school work.

Word processing software with predictive text and spellchecking facilities can often benefit children who have problems with writing. There are also many educational programmes that make use of text and sound to help improve a child’s reading.

Complications of spina bifida

Latex allergy

It is thought that as many as 20% of children and adults with spina bifida develop an allergy to latex. Latex is a type of naturally occurring rubber that is used extensively in the medical profession to create products such as latex gloves, masks and other clothing, as well as some types of medical equipment.

It is thought that latex allergies may occur because people with spina bifida are often required to spend a lot of time in medical environments, such as hospitals. They therefore receive more exposure to latex than most people. This over-exposure may trigger the development of a latex allergy.

The allergic reaction can range from mild to severe. Mild symptoms of an allergic reaction include skin rashes and watery eyes. A severe allergic reaction, known as anaphylactic shock, can be life threatening because the airways can narrow, causing serious breathing difficulties. Anaphylactic shock requires immediate treatment with an injection of adrenalin.

If you or your child develop a latex allergy you will need to tell all themedical professionals who are involved in your care or your child’s care, if they do not know already. Alternatives to latex can be used.

Some people with latex allergies also develop an allergy to foods that contain small amounts of latex. These foods include:

  • banana,
  • pineapple,
  • avocado,
  • chestnut,
  • strawberry,
  • soy,
  • mango,
  • kiwi fruit, and
  • passion fruit.

Shunt malfunction

If you or your child have had a shunt fitted to treat hydrocephalus, there is a small risk that it could become blocked. If this happens, you (or they) will experience a build-up of cerebrospinal fluid on the brain.

A shunt malfunction can be very serious because the excess fluid can cause brain damage. You should immediately contact your care team if you or your child experience the symptoms listed below.

Symptoms of a shunt malfunction in infants include:

  • a bulge in the infant’s skull,
  • an increase in the circumference of the head,
  • irritability,
  • poor feeding, and
  • abnormal, high-pitched breathing.

Symptoms of a shunt malfunction in older children and adults include:

  • headache,
  • nausea and vomiting,
  • lack of appetite,
  • increased irritability, lethargy or drowsiness,
  • changes in personality,
  • disorientation,
  • visual problems, such as double or blurred vision,
    fits and seizures, and
  • a sudden change in continence patterns, for example, urinary incontinence in a person with no previous history of the condition.

Surgery will be required to replace the malfunctioning shunt.

Psychological affects of spina bifida on parents

Being told your unborn baby has spina bifida can be a traumatic experience. It is common to have feelings of grief, anger, shock, fear and guilt. Parents are also concerned about what will happen in the months and years ahead, in terms of the extra support and care that their child will require.

If your child has spina bifida, you should feel free to discuss your concerns with your care team. Psychological support can also be made available to help you to cope with what is sure to be a difficult time.

Talking to other parents with experience of spina bifida is a good way to find out more about the practicalities of raising a child with the condition. It can also help you to cope with any fears or concerns that you might have.

Association for Spina Bifida and Hydrocephalus

The UK’s largest spina bifida charity is the Association for Spina Bifida and Hydrocephalus (ASBAH). ASBAH offers a wide range of resources for parents, as well as providing details about local support groups and organisations. See Useful links.

A challenging but rewarding experience

A recent American study carried out interviews with parents who had children with spina bifida. Many parents admitted that raising a child with spina bifida can often be a challenging, stressful and, sometimes, a frightening experience. All of the parents also said that raising a child with spina bifida was a rewarding and fulfilling experience.

Psychological affects of spina bifida on children and young people

Young children with spina bifida are often able to cope relatively well with the condition. Problems tend to develop as a child gets older and they begin to mix with other children.

During this period, the child starts to become more aware of how their condition makes them different to other children. This can cause some older children with spina bifida to become reserved and withdrawn, while others may begin to exhibit challenging behaviour due to a sense of anger or frustration.

Encouraging your child to participate in activities with other children can help to boost their self-esteem and confidence.

The teenage years

Teenage years can be a particularly difficult time both for young people with spina bifida and their parents. Tensions can develop as many young people desire an increased level of independence, which some parents can be reluctant to give. Trying to increase your child’s independence while protecting them from harm can sometimes be a difficult balancing act.

One educational specialist recommended what he termed a ‘driving instructor’ approach. The approach involves adopting a similar method to the one that a driving instructor takes towards his pupil. This meansconstantly teaching them new skills while at the same time always monitoring their progress and intervening to protect them from harm when necessary.

Sex and sexuality

Sexuality can also be a sensitive area for young people with spina bifida. Like other teenagers, as they go through puberty they will develop sexual feelings and a sexual identity. However, a young person with spina bifida will be naturally concerned about how their condition may impact on their ability to develop and maintain intimate relationships.

Teenagers are often reluctant to discuss these kinds of intimate issues with their parents, so they may benefit from talking to other qualified adults, such as a nurse or a social worker.

There is no reason why young people with spina bifida cannot experience normal adult sexual relationships as they get older. Some men with spina bifida may experience erectile dysfunction as a result of nerve damage. However, this can usually be treated using medicines such as sildenafil (Viagra).

Preventing spina bifida

Folic acid

The most effective way to prevent spina bifida is to take folic acid supplements both before and during pregnancy.

The Department of Health recommends that all women who are trying to get pregnant should take a daily supplement of 0.4mg of folic acid. You should also take this supplement for the first 12 weeks of pregnancy, when your baby’s spine is developing.

Women who are thought to be at higher risk of giving birth to a child with spina bifida, such as women with diabetes or those who are taking anti-epileptic medicines, may need to take a higher dose of folic acid. Your GP will be able to advise you about this.

Folic acid tablets are available on prescription or from pharmacies, large supermarkets and health food stores.

Natural sources of folic acid include:

  • green leafy vegetables,
  • breakfast cereals, and
  • bread.

If you are on medication for a condition such as epilepsy it is important to check with your GP before taking folic acid. This is because some types of medication can cancel out the effects folic acid supplements.