Most women carrying twins, triplets or more will go on to have healthy babies

Women pregnant with twins, triplets or more are often alarmed to find themselves automatically placed in a ‘high-risk’ category. In fact, most women carrying twins, triplets or more will go on to have uneventful pregnancies and healthy babies.

However, there are conditions that can arise in any pregnancy, such as anaemia, preeclampsia or gestational diabetes, which are more common in multiple pregnancies and are therefore worth watching out for.

There are also some complications that arise only in twin, triplet or more pregnancies. These are rare, but when they happen they do need medical attention and monitoring.

Fortunately, much more is known about these rare conditions than was once the case, and the medical expertise now available is outstanding – as parents of twins, triplets or more who have dealt with such problems can testify.

A woman pregnant with twins, triplets or more
What to look out for in a multiple pregnancy

If you are concerned about any of the issues listed below, talk to your doctor or midwife. You can also ring Twins Trust’s freephone helpline Twinline on 0800 138 0509. This confidential listening service is staffed by volunteers who are parents of twins, triplets or more themselves and have had training in the issues that can affect a multiple pregnancy. Twinline is open Monday – Friday from 10am-1pm and 7pm-10pm.

Here’s a brief list of what to watch out for.

This is a rare complication that only affects twins who share a placenta (Monochorionic). In TTTS, a blood transfusion occurs from one twin (the ‘donor’) to the other (the ‘recipient’). The donor twin becomes smaller and may suffer anaemia, while the recipient twin is put under strain. Often the donor twin also has less amniotic fluid but the recipient has lots, which can cause the mother’s belly to become larger than would be expected. If TTTS is diagnosed, your pregnancy will be closely monitored by frequent ultrasounds to check on the babies’ growth. If necessary, you may be offered laser ablation therapy to separate the blood vessels in the placenta. Twins Trust has developed a range of TTTS resources to provide you with more information on the condition.

Although monochorionic monoamniotic twin and triplet pregnancies are very rare, they have a high risk of adverse pregnancy outcomes (MCMA pregnancies occur in about 1 in 10,000 pregnancies overall and triplet pregnancies occur in about 3 per 10,000 pregnancies).

Anaemia occurs when your blood doesn’t have enough healthy red blood cells to carry oxygen to your tissues and to your baby. Symptoms are feeling tired, looking pale, being short of breath and fainting. A diet rich in iron will help keep haemoglobin levels up. Foods to go for are red meat, lentils, haricot beans, dark green vegetables and breakfast cereals fortified with iron. You can also take supplements (if they cause constipation, get plenty of fluid and fibre; changing brand may help).

Symptoms include a rise in blood pressure and/or protein present in urine, so both of these will be regularly monitored. It may be associated with symptoms such as swelling of the face, sudden swelling or puffiness of ankles and hands, severe headaches, affected vision, and in more severe cases, pain in the upper abdomen. If you suffer any of these symptoms, contact your healthcare team immediately. You may need hospital care and bed-rest to reduce the blood pressure, and in severe cases the babies may need to be delivered early. If this happens, steroid injections may be given to help their lungs develop before being born.

The physical symptoms may at first seem like preeclampsia but HELLP syndrome can be difficult to diagnose, especially when high blood pressure and protein in the urine aren’t present.

Pregnant women develop HELLP Syndrome have reported experiencing one or more of these symptoms.

Headache, nausea/vomiting/indigestion with pain after eating, abdominal or chest tenderness and upper right side pain, shoulder pain or pain when breathing deeply, bleeding, changes in vision and swelling.

HELLP Syndrome can be life-threatening so it is important to seek medical help urgently. Both Hellp and preeclampsia usually occur during the later stages of pregnancy or sometimes after childbirth.

Most often the definitive treament for women is the delivery of their baby.


Most twins and triplets grow normally in the womb, although they do tend to be a little smaller than singleton babies.  In all pregnancies however, there is a risk that the placenta(s) will not keep pace with the needs of the growing baby and this can cause their growth to slow down.  This can put the baby, or babies, at risk if it goes unrecognised. Fetal growth restriction is more common in twin pregnancies and even more so in triplets and higher order multiples.  Regular ultrasound scans will be offered to you to monitor the growth of your unborn babies.  Premature delivery is sometimes recommended if one or more of your babies is very small.

The most common gestation for the onset of labour in twin pregnancies is approximately 37 weeks.  However, labour may occur earlier than this, particularly with multiple births. The signs and symptoms of preterm labour are regular contractions of the womb, building up in strength and frequency, sometimes with passage of the mucous plug (‘show’) or breaking of the waters.  Premature tightening (often referred to as braxton hicks) are a common occurrence in pregnancy, particularly with twins and triplets, and in most cases they are not a sign of preterm labour.  However, it can be very difficult to determine if labour is imminent or not and if you experience these symptoms along with pain you should inform a health care professional immediately.  It is likely that you will be advised to go to hospital.  Although it is difficult to stop true premature labour, it can sometimes be delayed, giving time to prepare the babies for an early birth.

This is high blood sugar during pregnancy which is caused by your body not making/using enough insulin. Symptoms include feeling very hungry or thirsty, needing to pass urine frequently, tiredness and blurred vision. These symptoms are not always noticeable, hence the need for regular urine testing at antenatal appointments. Gestational diabetes shouldn’t be a problem once it has been detected. Treatment involves dietary changes, close monitoring and sometimes medication in tablet form or insulin.

One in four multiple mothers in a Twins Trust survey reported some vaginal bleeding or spotting in pregnancy. It is usually harmless. However, it is essential to tell your doctor immediately should it happen to you so that serious complications – such as ectopic pregnancy or problems with the placenta – can be ruled out.

This is a liver condition where the normal flow of bile is impaired and bile salts build up in the blood. The main symptom is severe itching, often on the hands and feet. Other symptoms are fatigue and sleep deprivation from itching, loss of appetite, dark urine and/or pale stools, and mild depression. The treatment involves regular monitoring and medication to reduce the bile acids in the bloodstream. It is sometimes necessary to deliver the babies early to protect them. You can help your body by cutting down on fatty and fried foods so your liver has less work to do. Drink lots of water. Keeping cool may reduce itching, as may a cool shower and soaking your hands and feet in icy water before bed.


Our Complications Guide is designed to help you to understand some of the conditions associated with twin, triplet and higher-order pregnancies. Although these complications are rare, we hope the information in this booklet will help you understand what to expect if you are diagnosed with any of these conditions.

We are researching and campaigning for better care for families with multiples

Over recent years, Twins Trust has followed a strategy of undertaking, commissioning and encouraging research so we can better understand our families’ experiences with twins, triplets or more. The findings from our research can be found in our recent reports. This research has enabled us to campaign to seek improvements in the care families’ receive. 

Twins Trust will be commissioning further research over the coming years to help improve the care for parents with pregnancy complications, such as MCMA pregnancies and Twin to Twin Transfusion Syndrome. Keep an eye on our website and social media channels for updates.

Bereavement support

Sadly there will be some rare circumstances in which one or more multiple pass away. If this has happened to you, our Bereavement Team is here to support you.

Our Early Pregnancy Workshop is aimed at pregnant women and their partners before 20 weeks. Get your questions answered in a friendly, non-judgmental environment.