A Guide to Twin-to-Twin Transfusion Syndrome

For Every Birth. For Every Baby. For Every Family.

Pregnancy is a time when expectant mothers and families rely heavily on the advice of medical professionals, trusting that the care and treatment they provide will be competent, timely and appropriate.

However, having supported countless families affected by medical negligence, our specialist lawyers have seen how avoidable errors and failings, can place both the mother and her babies at significant risk of harm or injury, often with serious and life changing consequences.

At Fletchers Solicitors, we have extensive experience and expertise in all types of obstetric negligence and birth injury claims. Our dedicated team of solicitors are committed to securing the best possible outcome for every family that we represent, helping them not only to achieve justice and financial compensation, but also ensuring they have the long-term support required to navigate life after a birth injury.

In this guide we cover:

• What Twin-to-Twin Transfusion Syndrome (TTTS) is and which pregnancies are at risk
• The causes of TTTS and how it develops during pregnancy
• Common symptoms and warning signs affecting both mother and babies
• How TTTS is diagnosed, including ultrasound monitoring and Quintero staging
• Available management and treatment options, including laser therapy and early delivery
• Survival rates, potential complications, and long-term outcomes
• Whether TTTS can be prevented and the importance of early detection
• When medical negligence may arise in TTTS cases
• The legal criteria for making a TTTS negligence claim
• The types of harm that may be considered in a claim (physical, emotional, financial)
• How specialist birth injury lawyers can support families

What Is Twin-to-Twin Transfusion Syndrome?

Twin-to-twin transfusion syndrome (‘TTTS’) is a rare, but potentially fatal condition that affects approximately 10-15% of identical twins that share a placenta (monochorionic), as well as triplets and higher order pregnancies with a shared placenta.

The risk is higher for monochorionic diamniotic (‘MCDA’) twins, who share a single placenta but have their own separate sacs. However, it can also affect monochorionic monoamniotic (‘MCMA’) twins, who share both a placenta and a sac, though this is much less common.

Dichorionic diamniotic (‘DCDA’) twins, also known as non-identical twins, are not at risk of TTTS as they each have their own placenta and separate sacs.

What Causes Twin-to-Twin Transfusion Syndrome?

TTTS is caused by abnormal connecting blood vessels in the twins’ shared placenta. Usually, the blood vessels allow blood to flow evenly between each baby, however, in TTTS there is an imbalanced blood flow from one twin (the donor twin) to the other twin (the recipient twin).

TTTS can happen at any time during pregnancy, though it typically develops between 16 and 26 weeks gestation.

What are the Possible Indicators of Twin-to-Twin Transfusion Syndrome?

Symptoms of TTTS vary depending on the severity and stage of the condition. However, where TTTS is present, the mother may experience feelings of abdominal pain, tightness or discomfort around the stomach, early uterine contractions, breathlessness, increased thirst and heart palpitations. If there is a build up of amniotic fluid, this may cause sudden noticeable weight gain (even within just 24 hours) as well as back and leg pain.

As a result of the blood flow imbalance, the recipient twin will usually be larger, with a higher blood volume. To compensate for this, the recipient twin’s heart has to work harder to pump the extra blood, putting strain on their heart and increasing their risk of heart failure. They will also often produce a large amount of urine leading to increased amniotic fluid (polyhydramnios).

Whereas the donor twin will normally be smaller in size, with a reduced amount of amniotic fluid (oligohydramnios) due to decreased urinary output. Often their bladder may appear small or not be visible at all on an ultrasound.

How Is Twin-to-Twin Transfusion Syndrome Diagnosed?

In all twin pregnancies, the sonographer should check whether your twins are monochorionic or dichorionic during your first ultrasound. If they are monochorionic, you should receive close monitoring with ultrasound scans on a fortnightly basis, from 16 weeks until birth.

If there are any concerns about differing levels of amniotic fluid, during the second or third trimester, you should be referred to your specialist obstetrician for further assessment. Diagnostic monitoring for TTTS should also be increased to no less than weekly and should include Doppler assessments to check the umbilical artery flow (deoxygenated blood flow) of each twin.

TTTS is usually diagnosed during routine ultrasound scanning in the second trimester, due to findings such as inconsistent levels of amniotic fluid, growth restriction in the donor twin, or increased growth in the recipient twin. However, further investigations such as Doppler studies and fetal heart monitoring should also take place to confirm the diagnosis.

When diagnosing TTTS, a classification system, known as ‘Quintero staging’, will be used to determine the severity of the TTTS. The stages range from Stage I (discrepancy in amniotic fluid with a visible bladder in the donor twin) to Stage V (death of one or both twins).

In our experience of TTTS negligence claims, early and accurate diagnosis is crucial for ensuring timely intervention and improving the outcomes for both twins. Therefore, it is very important that medical professionals are aware of the warning signs, and that both the mother and babies receive close monitoring to identify any potential indicators of TTTS during pregnancy.

How Is Twin-to-Twin Transfusion Syndrome Managed and Treated?

The appropriate management of TTTS will depend on gestational age, the Quintero stage (severity), and the overall health of both twins.

However, if TTTS is diagnosed, the pregnancy should always be closely monitored through frequent ultrasound scans to check on the twins’ growth. The mother should also be referred to a fetomaternal specialist, to discuss the suitable treatment options.

Management and Treatment Options

For mild cases (Stage I), increased ultrasounds and Doppler studies may be recommended to watch for progression before intervening.

In moderate to severe cases (Stages II-IV), intervention by way of fetoscopic laser ablation (laser therapy) will usually be recommended. This aims to save one or both of the babies by separating the abnormal connection of blood vessels, stopping the blood flow imbalance. It is often an effective method at improving outcomes, however, vessels that are deeper than the placenta may not always be visible. Therefore, close monitoring will still be required until birth, in case the imbalance returns.

Other less frequently used treatment options include: amnioreduction (draining of excess fluid), septostomy (creation of a hole between the two amniotic sacs to balance fluid levels) and selective termination (termination of one pregnancy, used only in extreme cases).

Early Delivery 

If severe TTTS develops or worsens after 26 weeks, when the babies can survive outside of the womb, early delivery will usually be recommended. This is because TTTS ceases at birth, when the twins are no longer connected by the placenta. Whereas if the TTTS improves, either on its own or following laser therapy, delivery should take place at 36 weeks gestation, unless any other complications are noted.

However, all twin pregnancies are at higher risk of preterm labour (before 37 weeks), and this risk is further increased when TTTS is present. Therefore, the mother may also be offered corticosteroids (steroid medication) where delivery is likely within the next 7 days, to reduce the risk of either twin suffering respiratory issues at birth.

Twin-to-Twin Transfusion Syndrome Survival Rates

We understand that a diagnosis of TTTS can bring considerable fear and anxiety. However, it is important to note that not all women with TTTS will develop complications and with early detection, expert fetal monitoring, and timely intervention, the outcomes for both twins can be significantly improved.

The risk of preterm labour is significant in TTTS pregnancies, and premature delivery places both twins at greater risk of death, or long-term issues arising from respiratory distress, undeveloped bones or organs and digestive disorders.

TTTS can also result in long-term neurological complications, including cerebral palsy, severe developmental delay in motor skills and/or cognition, blindness in both eyes, and deafness.

Whilst the likelihood of premature delivery remains high, both with and without treatment, laser therapy can significantly reduce the risk of issues arising from premature birth and the long-term complications associated with TTTS.

It has also been shown to considerably increase the chance of survival for one or both twins, with an estimated survival rate of around 80% to 90% for at least one twin, and around 50% to 60% for both twins. Whereas without treatment, the survival rate for both twins is thought to be less than 20%.

Can Twin-to-Twin Transfusion Syndrome be Prevented?

Unfortunately, TTTS is not currently preventable as the exact reason for the imbalanced blood flow remains unclear. However, TTTS is not thought to be genetic nor hereditary, and it can happen in any MCDA or MCMA twin pregnancy. Though certain factors which may increase the risk of TTTS, include a history of TTTS in previous pregnancies, placental abnormalities or irregular umbilical cord attachment.

Ensuring that mothers and medical professionals are aware of the warning signs and indicators of TTTS is, therefore, key to allow for early diagnosis and intervention.

When Might Twin-to-Twin Syndrome Negligence Arise?

All twin pregnancies face additional risks, and for those diagnosed with TTTS, complications may still arise, even despite the best efforts of medical professionals. However, the chances of a positive outcome are greatly increased with optimum monitoring, management and treatment.

TTTS negligence may arise where the mother and/or her babies have suffered avoidable harm or injury, as a result of substandard medical care during pregnancy.

Common examples of TTTS negligence include:

• Failing to recognise, or misinterpreting warning signs and indicators leading to a failure to diagnose, or a delayed diagnosis of TTTS
• Inadequate monitoring during pregnancy, following diagnosis or treatment of TTTS
• Inaccurate Quintero staging of TTTS, due to incorrect measurements or inadequate use of diagnostic tools
• Delayed or inappropriate management following diagnosis of TTTS, such as delayed referral to a fetomaternal specialist or a delay in carrying out laser therapy
• Providing inadequate or inaccurate advice, including a failure to advise the mother about a TTTS diagnosis, or providing misinformation in regard to the risk of TTTS and the associated complications

Sadly, having dealt with many cases involving TTTS negligence, we know that the consequences can be truly devasting, not only for the expectant mother and her babies, but for the entire family.

When Can You Make a Twin-to-Twin Transfusion Syndrome Negligence Claim? 

All medical professionals have a legal duty to provide their patients with a reasonable standard of care, expected of any competent practitioner.

In order to bring any type of medical negligence claim, it is necessary to prove both of the following:

1. That the medical professional(s) involved breached their ‘duty of care’, meaning that the medical care which you received, fell below a reasonable standard, such that no responsible body of medical practitioners practising in that area e.g. maternity care, would have acted in the same way; AND
2. That you or your babies suffered harm or injury, and that there is a more than 50% chance that such harm or injury was caused, or contributed to, by the breach of duty of care.

This means that even where it is clear that the care provided to you, fell below a reasonable standard, it is unlikely that you would be able to bring a medical negligence claim, if there is no evidence that you or your babies have suffered any harm or injury, as a result of the substandard care. For example, if there was a failure to diagnose TTTS during your pregnancy, but both twins were born alive and well, it is unlikely that a claim would succeed.

However, harm and injury can be physical, emotional and/or financial and it need not be significant or ongoing, in order to make a .

For example, physical harm may include brain injuries such as cerebral palsy, vision or hearing problems or additional pain and discomfort for the mother.

Mothers may experience symptoms of emotional harm or psychiatric injury, such as distress, anxiety, or even post-traumatic stress disorder, particularly if they have suffered the loss of one or both twins.

Families may suffer financial losses, such as travel expenses associated with travelling to additional hospital appointments, loss of earnings if they have had to reduce their hours or stop working due to the negligence or the costs of private therapy or counselling.

How Our Birth Injury Lawyers Can Help

TTTS negligence claims, can be notoriously complex, requiring comprehensive knowledge and understanding of medical terminology and procedures, as well as experience of dealing with cases involving catastrophic injuries.

However, they are also highly sensitive and having an intimate understanding of the significant emotional and financial strain that such injuries can bring to a family, is crucial in any obstetric negligence or birth injury claim.

As one of the largest and most respected specialist birth injury teams in the UK, Fletchers Solicitors have been helping families to secure maximum compensation payments for over 30 years.

Our dedicated legal team have vast knowledge and experience of all types of obstetric negligence and birth injury claims, as well as strong relationships with many leading medical and financial experts.

We are committed to ensuring every family is treated with the upmost compassion, empathy and respect, supporting them every step of the way, even after settlement.

Our Experience in Twin-to-Twin Transfusion Syndrome Negligence Cases

Partner and Medical Negligence Consultant, Andrea Rusbridge has 37 years of experience in dealing with various types of medical negligence cases, comprising of many complex, high-value obstetric negligence and birth injury claims.

Regarded as an expert in her field, Andrea has secured millions of pounds in compensation for her clients, helping them to rebuild their lives after medical negligence. Her unwavering client care ensures that every client and family she represents is guided and supported throughout the whole process.

Having dealt with a number of twin pregnancy claims, Andrea has seen first-hand how challenging it can be to prove medical negligence in these types of claims, especially where TTTS is involved. However, often mothers and families are just seeking answers, as to whether any harm or injury to their babies could have been avoided.

Therefore, having the specialist knowledge and expertise required for these types of claims is crucial in ensuring that every case is thoroughly investigated with meticulous detail, leaving no stone unturned.

“These claims are complicated and difficult because there are risks inherent with any kind of pregnancy, but especially so in high-risk twin pregnancies. Although these cases are rare, with the right treatment and continuous monitoring, TTTS can be managed whilst still being conscious of the dangers associated with all high-risk pregnancies.” – Andrea Rusbridge, Partner and Medical Negligence Consultant

What Are the Three Types of Twin Pregnancies?

• Dichorionic diamniotic (‘DCDA’) twins: Non-identical twins, who each have their own placenta and separate sacs. They are not at risk of TTTS.
• Monochorionic diamniotic (‘MCDA’) twins: Identical twins, who share a single placenta but have their own separate sacs. They have the highest risk of TTTS.
• Monochorionic monoamniotic (‘MCMA’) twins: Identical twins, who share both a placenta and a sac. They are also at risk of TTTS, but it is much less common.

Who Can Make a Claim for Twin-to-Twin Transfusion Syndrome Negligence?

Where one or both of the twins are born alive but with complications, a claim can be brought on their behalf, usually by one of their parents. The twin(s) will be known as the ‘Claimant(s)’, and the parent will act as their ‘Litigation Friend’.

Where the negligence has sadly resulted in the death of one or both twins, following delivery (i.e. a neonatal death), a claim may be brought on behalf of the deceased twin(s), normally by one of their parents. The mother may also be able to bring a claim on her own behalf, for any psychiatric injury that she has suffered, if the negligence occurred prior to delivery.

However, where the negligence has sadly resulted in the death of one or both twins, prior to delivery (i.e. a miscarriage or stillbirth), only the mother may bring a claim on her own behalf, for any physical and psychiatric injury that she has suffered. This is because the law classifies an unborn baby and the mother as one legal person, but where the baby is born alive, even if only for a short time, the law considers the baby to be its own legal person.

In either scenario, fathers are not usually permitted to bring a claim on their own behalf, for any psychiatric injury they have suffered.

We recognise that these differences can feel deeply unfair, especially for fathers. However, the law does provide different ways to seek justice and recognition in both cases.

How Long Do I Have to Make a Claim?

The general rule is that a Claimant has 3 years to make a claim either from the:

• Date of negligence or death; or
• Date of knowledge, which is the date on which they first became ‘reasonably aware’ that they may have suffered an injury, or that the death may have been caused, or contributed to, by medical negligence.

However, where the Claimant is a child, a claim can be brought any time before their 18^th birthday. Once they turn 18, and providing they have mental capacity, the 3-year rule will then apply.

Where the Claimant does not have capacity to conduct legal proceedings, no time limits apply. This will often be the case in TTTS negligence claims, where one or both twins have suffered a brain injury.

How Much Does It Cost to Make a Claim?

We know that cost is one of the biggest worries for families thinking about bringing a claim. However, all of our medical negligence claims can be dealt with on a ‘No Win No Fee’ basis, removing any financial barriers and ensuring that every family affected by medical negligence can pursue their claim with confidence.

How Much Compensation Could I Receive?

The amount of compensation which is awarded in TTTS negligence claims can vary significantly, depending on a number of factors, including the severity of the injuries/complications, the costs of any future care, treatment and accommodation and the wider impact, not only upon the Claimant, but also their family .

However, typically the compensation will include ‘general damages’ for any pain, suffering and loss of amenity which the Claimant has suffered as a result of the negligence and ‘special damages’, relate to any ‘out of pocket’ expenses and financial losses which the Claimant, and/or their family members, have incurred or which they are expected to incur in future, as a result of the negligence. Additional types of compensation may also be awarded where the negligence has resulted in the loss of one or both twins, following delivery.

GET IN TOUCH TODAY

We strongly advise families to seek legal advice as soon as possible. If you have recently experienced TTTS during pregnancy, and you have concerns about the standard of care which you or your babies received in regard to this, please contact us.

We will then arrange a free no-obligation discussion with one of our specialist lawyers, to help you understand whether you have a potential claim.