As recently reported in the media, a drug used for erectile dysfunction is being trialled on labouring women, to reduce fetal distress.

For the last 18 months, a research trial has been under way, using the drug Sildenafil (brand name Viagra) on women giving birth.

University of Queensland professor, Sailesh Kumar, from the Mater Research Institute, said there were promising results from the Sildenafil trial.

Viagra Trial To Reduce Fetal Distress In Labour

The trial, which involves 230 women, suggests using Sildenafil during labour could reduce fetal distress, lowering the risk of further interventions such as forceps or c-section.

How Does Viagra Work?

Viagra first hit the market in the late 1990s. It was initially designed to treat hypertension and angina pectoris, but is commonly prescribed to men for erectile dysfunction.

Viagra only works when a man is sexually stimulated. When sexual stimulation occurs, nitric oxide is released by the nervous system, which then signals an enzyme that produces cyclic guanosine monophosphate (cGMP).

cGMP causes the blood vessels in the penis to relax and expand, so the arteries and the erectile tissue fill with blood, resulting in an erection. An enzyme called PDE5 breaks down cGMP and reduces blood flow. PDE5 is found in the brain, lung tissue, heart, liver, kidneys, bladder, prostate, urethra, penis, uterus and skeletal muscles.

Viagra inhibits PDE5, so the blood flows and the erection can continue.

Viagra is rapidly absorbed into the bloodstream; maximum concentrations are reached within one hour of taking the drug. All traces of the drug have left the body 24 hours after it has been taken.

How Can Viagra Help Reduce Fetal Distress?

The Mater Mothers’ Hospital trial is an Australian first, and early results are said to show an almost 50% reduction in the number of women requiring an emergency c-section or a forceps delivery for fetal distress when they take Sildenafil in the early stages of labour.

Professor Sailesh Kumar said the premise of the trial was Sildenafil could increase blood flow to the uterus and placenta during labour, improving the transport of oxygen and nutrients to the placenta and the baby.

In theory, this increased flow of oxygen and nutrients could reduce the risk of babies becoming distressed in labour, which could lead to instrumental or surgical birth.

What Is Fetal Distress?

When babies are unwell while still in utero, they are said to experience fetal distress. The term is commonly used to describe a situation where a baby isn’t receiving enough oxygen during pregnancy or birth, but reduced oxygen isn’t the only cause of fetal distress.

There are several reasons fetal distress occurs, due to oxygen interruption:

Maternal position (lying on your back compresses a major vein which reduces oxygen flow to the baby)
Problems with the placenta, such as abruption
Maternal illness, such as preeclampsia or high blood pressure
Prolapse, or compression of the umbilical cord
Infection

Induction of labour using artificial oxytocin has also been implicated in causing fetal distress. The use of Pitocin or Syntocinon increases the risk of uterine hyperstimulation and fetal distress.

After they were admitted to hospital for labour, the women in the trial were given either Sildenafil or a placebo. In the trial, labour is defined as ‘cervical dilatation ≥4 cm with uterine contractions or at commencement of induction of labour with artificial rupture of membranes and/or oxytocin infusion’. It isn’t clear how many women so far in the trial have been induced and how many have gone into labour spontaneously.

Is Viagra Safe For Women and Babies?

A Dutch study trial using Viagra during pregnancy has been urgently stopped after eleven newborn babies died.

The study was being run across 11 hospitals and involved almost 200 women. Of these, 93 women were given Sildenafil to boost the growth of their babies due to poorly developed placentas.

When the placenta doesn’t develop properly or well, it restricts oxygen and nutrients being passed to the baby, which can lead to intrauterine growth restriction (IUGR). This can cause potential complications such as premature birth, low birth weight, low APGAR scores (the test used to check baby’s wellbeing after birth), decreased oxygen level, and stillbirth. To date, there is no treatment for IUGR.

The Dutch trial started in 2015 and was due to run for another two years. It has been halted after 17 babies in the Sildenafil group developed lung problems after birth. Eleven babies died due to lung complications. It’s thought the drug has caused high blood pressure in the lungs, resulting in the babies not receiving enough oxygen.

Experts are calling for a full investigation into what happened during the trial, although it’s believed the study was conducted properly and there is no suggestion of it being mishandled. A previous trial of 135 British women found no evidence of potential harm from using Sildenafil during pregnancy for IUGR. But it also found no benefit for babies with IUGR. Similar findings came from trials out of Australia and New Zealand. Canadian researchers a undertaking similar study to the Dutch one have halted their research.

What is also of concern is the long list of potential side effects of using Viagra for its original purpose, as a drug for erectile dysfunction.

The most common side effects are:

Headaches and dizziness
Flushing or a rash
Nausea and upset stomach
Photophobia (sensitivity to light)
Stuffy or runny nose
Back or muscle pain

More serious, although less common, complications are:

Heart attack
Sudden hearing loss
Increased fluid pressure in the eye
Heart rhythm disorders

Should We Use Viagra For Labour?

The question we should be asking is why a drug used for erectile dysfunction is necessary during labour? The drug is being trialled to ‘reduce fetal distress’ and consequently to lower the risk of cerebral palsy and stillbirth.

Research, however, shows only a very small number of cases where cerebral palsy occurs as a result of birth hypoxia (oxygen deprivation during labour). Some studies suggest this is less than 10% of all cases of cerebral palsy.

Stillbirth – the loss of a baby after 20 weeks gestation – is a tragic event, yet the most common cause is due to birth defects. Approximately 2% of stillbirths in Australia are attributed to lack of oxygen during birth.

Unfortunately, as the halted Dutch trial shows, Viagra has the potential to cause devastating effects on newborns. While this Australian trial only gives the drug during labour, is the potential negative outcome on babies worth the risk? Is the medication trying to improve outcomes which are just as likely a result of birthplace policies and care provider attitude?

Are the women in the trial experiencing health conditions that increase fetal distress? Are the women being induced or waiting for labour to begin spontaneously? Are the babies in the trial monitored afterwards to determine whether there are any side effects?

Before we can champion the use of yet another medical intervention being lauded as a positive step forward in maternity care, we need to ask whether this intervention is even necessary?

It’s difficult to get figures on how many babies experience fetal distress during labour, but we know the diagnosis of fetal distress increases the risk of having a c-section birth. C-section rates are higher than those recommended in guidelines provided by leading health experts. A drug that could reduce fetal distress and therefore instrumental birth could be considered a boon.

However, a fetal distress diagnosis happens when care providers use electronic fetal monitoring (EFM) to determine how a baby is coping in labour. EFM has been linked to a higher risk of c-section and is not evidence based practice, despite being routinely used in hospitals, especially for inductions. You can read more about this in Electronic Fetal Monitoring In Labour Increases Risk Of C-Section.

For many women, labour happens in less than optimal conditions, such as busy, brightly lit hospital rooms with unknown staff and time/policy pressures. When a mother is stressed during labour, her body increases production of adrenaline and labour slows down. This can have a knock on effect of causing babies to experience distress.

The vast majority of births take place in hospital, where women are at risk of:

Inductions for non medical reasons (past estimated due date, care provider absence, maternal preference)
Electronic fetal monitoring (non evidence based practice used routinely to monitor multiple women)
Requesting an epidural (often as a result of induction, or if women aren’t being supported to have an undisturbed labour, increasing distress)
Restricted labour positions (due to EFM, care provider preference, induction or epidural in place)
Having their labour disturbed, which leads to a stall or failure to progress (there are many ways labour can be interrupted negatively).

It would make more sense for research and practice to focus on, and implement, ways maternity care could be improved, so as to avoid these situations and make the use of a drug unnecessary in the first place.

Can I Improve Uterine Blood Flow Without Viagra?

As part of preconception and pregnancy care, women can improve blood flow to the uterus naturally, by doing the following:

Increasing intake of foods rich in nitrate, such as beetroot and dark leafy greens. Improved circulation and reduced blood pressure occur when dietary nitrate (NO3) is converted to biologically active nitrate (NO2) and then into nitric oxide (NO).
Supplementing with L-Arginine. This amino acid promotes the conversion of nitrate into nitric oxide.
Moving the body, which increases the blood flow to the uterus and pelvic area. A sedentary lifestyle (too much sitting down) compromises the flow of blood to the lower half of the body, including the uterus. Walking, yoga and dancing (especially forms which encourage the shaking and movement of hips) can all promote better blood circulation to the pelvis.
Massage therapy can also improve blood flow to the uterus. Mayan abdominal therapy is external, noninvasive massage which aims to correct a tipped or prolapsed uterus, which can compromise blood flow in the area.

For women who need to be induced for strictly medical reasons, care providers could introduce an optimal environment and positive continual support to increase the chances of these women being able to labour and birth vaginally with fewer interventions.

What do you think? Is the use of Viagra to prevent fetal distress a medical boon, or should care providers do more to avoid the reasons why fetal distress occurs during labour?