The art and science of twins.

A joint meeting of the Section of Paediatrics and Child Health and the Forum on Maternity and the Newborn of the Royal Society of Medicine, Tuesday 20th March 2007.

Chair, morning session: Professor Lewis Spitz, President of the Section of Paediatrics & Child Health, RSM
Chair, afternoon session: Dr. Luke Zander, retired General Practitioner and teacher and founder of the Forum

The work of the Multiple Births Foundation
Mrs Jane Denton (JD), Director, The Multiple Births Foundation, Queen Charlotte's & Chelsea Hospital, London

The Multiple Births Foundation (MBF) aims to provide advice and information to families with multiple births and to raise the awareness of professionals about the needs and care of these families, along with training on how to meet these needs. Parents need consistent information focused upon multiple birth, not extrapolated from singletons, and given as soon as the diagnosis is made without exaggerating the problems or painting an unrealistically rosy picture. MBF guidelines recommend what information should be given at this time. This includes details of the care pathway and emphasises the importance of the professionals involved being sufficiently well informed to give parents confidence. Misinformation, e.g. that dichorionic twins can never be identical, is still only too common. Knowiing the zygosity is very important for the parents and children themselves when older. Establishing the identity and individuality of each child from birth is an important factor which underpins their whole development. Contact with parents of twins and triplets can be a great help.

Screening in multiple pregnancy such as that for Down's syndrome is more complex, and the MBF is producing a leaflet on the subject. Information on preterm birth and the care and procedures in a neonatal unit help prepare parents, as prematurity is more likely to arise with multiple births. Prenatal education should include how to manage the common problems of the early years - feeding, sleeping, growth, language and relationships. Mothers of twins often report a lack of support for breastfeeding. An MBF project is under way to produce evidence-based guidelines and information for parents on feeding twins and triplets.

The medical complications of multiple pregnancy and the higher mortality and morbidity for multiple birth babies are well known. The MBF's view is that practice should aim to reduce the high twinning rate after IVF by replacing one embryo in women with a good chance of conceiving.

Sleeping arrangements for twins have been researched (Ball 2006); it is important that professionals give safe advice appropriate to each family. With twins or more the mother's attention is divided, and language development can be hindered by a lack of eye contact and one to one dialogue. (Thorpe 2006); the children benefit from time apart, which also helps their development of individuality. Dressing them differently helps other people to identify them individually. If possible time spent with each parent separately is to be encouraged.

The incidence of cerebral palsy with its impact on families is now about five times higher in twins and eighteen times higher in triplets than in singletons (Petterson et al. 1993). We have separate leaflets for professionals and families with guidance on the management of this and other disabilities. Giving the healthy child equal care and attention can be challenging for the parents. Other issues may be difficulties in bonding and the development of healthy relationships, the guilt of the healthy child and the frustration and jealousy of the disabled twin; parents frequently feel that they have insufficient time for either twin.

Mothers of twins and triplets are more likely to suffer from depression. Contributory factors are chronic fatigue due to pressures of coping with day to practicalities and lack of social contact. (Thorpe et al. 1991). One father commented in the Study of Triplets and Higher Order Births: Three Four and More "In the last two-and-a-half years my wife has only had one day off from looking after the children". There may be developmental problems in twins, and their siblings may show disturbed behaviour. This whole picture, which may include financial hardship, can lead to marital stress and possibly to child abuse. In the TAMBA membership survey of 2004 over a third of respondents reported that the relationship with their partner was the area of their life most affected. Families need support in bereavement, whether following the pre- or perinatal death of a baby or when selective termination has been carried out.

Services devoted to the needs of these families are at best patchy, and the most effective help is often given by other parents. Some parents travel far to attend a single talk on multiple pregnancy at Queen Charlotte's Hospital, a service supported by a local twins club, underlining the need for and shortfall in services for these families. The care of multiple pregnancies has to become more consistent, particularly in the case of monochorionic twins, where the special requirements frequently go unrecognised; informed by the Internet, anxious parents often become aware of this. Many areas of the multiple pregnancy scene need more research and audit. Improvement in interprofessional communication by the establishment of multidisciplinary teams is another essential need. Services for these families should be an integral part of all health and social care.


Ball, Helen L. (2006) Caring for twin infants: sleeping arrangements and their implications. Evidence Based Midwifery 4(1): 10-16

Thorpe, Karen J. (2006) Best practice: Twin children's language development. Early Human Development 82(6): 387-95

Thorpe K, Golding J, MacGillivray I and Greenwood R. (1991) Comparison of prevalence of depression in mothers of twins and mothers of singletons. British Medical Journal 302(6781): 875-8 Petterson B, Nelson KB, Watson L, Stanley F. (1993) Twins, triplets, and cerebral palsy in births in Western Australia in the 1980s. British Medical Journal 307: 1239–43.

For full information on the MBF and TAMBA go to

Sources of information and suggested reading:

Guidelines for professionals: multiple births and their impact on families. E.Bryan, J. Denton, F.Hallett. Multiple Births Foundation, London.

Multiple Births. Best Practice Guidelines. Early Human Development. Guest Editor: Elizabeth Bryan vol.82 2006, 363 -420. Multiple Births Foundation, London.

Multiple Pregnancy. Eds: Mark Kilby, Philip Baker, Hilary Critchley and David Field RCOG Press, London 2006.

Health and Welfare of ART Children. Ed: Alastair G Sutcliffe. Informa Healthcare UK. 2006


JD: Hard and fast indications for caesarean section for twins are lacking at present, and parents need to be informed of the consensus of the time; at present the Queen Charlotte's policy is delivery at 38 weeks where CS is recommended, but at 36 weeks for monochorionic twins, to avoid the dangers of twin-to-twin transfusion. RW: There are particular dangers in labour for monochorionic twins: the acute onset of twin-to-twin transfusion, and the rupture of the second twin's thin membrane following the delivery of the first, which may make delivery of the second difficult.

JD: In the matter of twins sharing a bed we give parents the relevant information and support them in their decision. It is important to avoid overheating and to observe the conditions which are believed to prevent sudden infant death; some twins get on well together, some not.

Iatrogenic multiple pregnancy and its consequences.
Dr Alastair G Sutcliffe (AS), Senior lecturer in child health, Institute of Child Health, University CollegeL, London

It is well known and a matter for concern that the rate of twin births has increased rapidly in Europe over the past two decades. 10% of this is due to rising maternal age, the other 90% due to assisted reproductive therapies (ART). Interestingly ART, although predominantly 'causing' a rise in dizygotic (DZ) twins, is also responsible for a higher incidence of monozygotic (MZ) twinning. The mechanisms for the latter and the direction of travel with respect to iatrogenic twinning and its sequelae will be referred to in this overview.

The increase in triplet births could be said to amount to an epidemic, although it is falling off at present. The Barker hypothesis (1992) suggests that in bad conditions a fetus can modify its development such that it will be prepared for survival in an environment in which resources are likely to be short, resulting in a 'thrifty phenotype'; the trend to low and yet lower birth weights of twins and triplets reflects this notion. This corresponds with the shorter average gestation for twins - 37 weeks - and triplets - and 34 weeks. The pre-term delivery rates, 24-32 weeks, are 5% for dichorionic twins, 10% for monochorionic twins and 25% for triplets, which are relatively much more prone to severe prematurity, less than 32 weeks. The perinatal mortality and the subsequent morbidity figures for multiple births correspond with these data, and the problems have been shown to relate to the chorionicity of the pregnancies, not the zygosity.

That the birth rate of DZ twins has been increased by ART is no surprise, but unexpectedly it is also responsible for an increase in the rate for MZ births, which are subject to a six times higher rate of loss in early pregnancy, and twice the rates for perinatal death, growth retardation, and preterm delivery. Families seeking ART need to understand this. A large American study showed an incidence of multiple birth in the general population of 0.19 per cent, while the rate was 6% following ART. In response to such figures the practice in Sweden is now to return only one embryo to the uterus in IVF procedures.

The parents of multiples are faced with a number of problematical factors - socio-economic, the rearing environment, and pre-school provision. The mothers experience a higher incidence of postnatal depression than the mothers of singletons. The siblings may have beneficial influences on a disabled twin, but they are prone to behaviour disorders and depression. A disabled twin may be labelled identical, but is practically anything but.

Returning three embryos to the uterus does not increase the chances of achieving a successful pregnancy; it does, however, increase the triplets rate.

There are public health implications. Multiple births increase the pressure on neonatal services; cot shortages may require transfers to remote units; twins are at increased risk of cerebral palsy, triplets more so. Despite these problems most twins are healthy, and the majority of problems are associated with prematurity. Today ART accounts for 90% of twinning; the increased incidence of multiple birth with age is probably due to increasing resistance of the ovaries to FSH, the production of which is accordingly increased.

Reference: Barker DJ, Martyn CN. The maternal and fetal origins of cardiovascular disease. J Epidemiol Community Health. 1992 Feb;46(1):8-11.


AS: Research shows the that selective reduction of embryos to avoid multiple birth and its complications is safe, but I am rather doubtful of this. Of course such decisions must be made jointly by obstetricians and families. KN: For untreated triplet pregnancies the miscarriage rate between 12 and 24 weeks is 3% and the severe premature delivery rate (24 – 32 weeks) is 25%. Embryo reduction from 3 to 2 increases the miscarriage rate to 8% because of the presence of dead tissue, but the severe premature rate falls to 15%. Irrespective of reduction 90% of babies survive; with reduction the incidence of disability is 1% per baby, without reduction it is 2% per baby i.e. 6% for triplets. Given this information half of the parents opt for reduction.

Whereas twins are celebrated in many cultures, and I enjoy caring for them, it is a fact that we have an epidemic of multiple birth with the associated problems.

If as some suspect there is a genetic basis for twinning, an understanding of it may be helpful for couples with fertility problems in the future.

A delegate referred to the growing consensus that single embryo transfer will probably and rightly become the rule.

Bringing up twins - A parent's view.
Ms Clare Rees (CR), Specialist registrar (Paediatric Surgery), formerly research fellow, Institute of Child Health, London

Research Aims: To explain the experience of parenting twins.
Methods: A twin pregnancy was conceived by previously described methods. At 6 weeks of gestation the diagnosis was made by ultrasound scan. Standard obstetric care was administered. Twins were delivered by emergency caesarean section on 25/07/2003. Infants were randomised to breast and bottle feeding. Data from the first six weeks is not available due to extreme exhaustion. Sleeping through the night was achieved at a median of 12months (range 0-42). Childminding and nursery education was applied as appropriate. Return to part-time work after 7 months was considered necessary for parental sanity.
1) Healthy fraternal twins (birthweights 2.18 and 2.48kg)
2) Two tired but delighted parents
3) At 3.5 year follow up all remain alive and kicking
Long term results awaited.
Parenting twins presents interesting challenges at various stages of pregnancy, birth and childhood, but the process is extremely rewarding. Long term follow up is recommended. Parents of larger multiples (triplets and quads) should be admired and respected.

On discovering that I was expecting twins I realised that even at age 33 I might have to apply to my father for funds. You don't need two houses when you have twins but you need enough space for them, and two baby seats require a large enough car. Fortunately other parents with twins are very happy to pass on the sort of items you need two of, and many shops offer discounts for twins, especially valuable being shoe shops.

It may surprise you that as a doctor my twin pregnancy surprised me; after all, I had none of six predisposing factors for twinning. When I had some bleeding, and thought it was all over, the ultrasound scan shocked my husband and me with the diagnosis of twins. The clinic midwife was hardly encouraging, warning me that I might not end up with two babies.

At my only consultation with a community midwife my list of questions about diet led her to refer me at once to an obstetrician; I discovered for myself that bedside biscuits were the answer to my morning sickness. My boss in the department of paediatric surgery was very supportive; I had imagined myself working until the 37th week when pregnant, but by 32 weeks I had had enough. Likewise the imagined three months off work after the berth had to be doubled.

Of course I expected all the known complications of multiple pregnancy, fortunately had none of them, but learned how hard it is to endure a twin pregnancy. The third trimester was instructive: I developed PUPPP. Please look this skin disease up on the internet, as I did; I was gratified that my condition resulted in an urgent consultation with a dermatologist, since the itching was intense. Sitting up to sleep in a very expensive chair relieved my insomnia.

I made the mistake of reading Professor Nicolaides's papers on fetal anomalies and their management; after what you heard here this morning you can understand my anxiety. I had an anomaly scan in my own department, and was relieved to learn that my baby would probably not need any of the operations which we do there; I decided not to inform myself about inborn errors of metabolism.

I found the twin specific antenatal class to be well worth while; we focussed less on breathing and so on, more on epidurals, caesarean section, special care and prematurity. Amongst my reading was a paper on the risk of delivery related perinatal death in twins, so I was relieved that my twin 1 was presenting by the breech, so that elective CS was recommended. I don't think that my presence in the class was appreciated by the other mothers, all of whom wanted vaginal deliveries. The appearance in my birth plan of elective CS with epidural had shocked them. Six of the seven had vaginal deliveries of the first twin but needed crash CS for the second, exactly what I wanted to avoid. The risk to the second twin at term was confirmed again by a paper published only last week.

I was warned to expect gentle rummaging in my abdomen, but in the event it felt as though the contents were being chucked out backwards; being aware of the significance of the sound effects and smell e.g. diathermy caused me some anxiety.

25th July Daniel was born weighing 2.48kg and Ilana 2.18kg, both healthy. At first I needed their different coloured blankets to tell them apart; I wasn't going to take off a nappy every time to tell which was the boy. We went home after two days; I can't remember the first six weeks, except that then as now every baby event happens twice.

It was a relief to know that my family is one of 10,000 in the country with twins.

This was good advice: when one twin wakes feed them both, and a routine develops. The two weeks of daily visits by a breastfeeding counsellor were invaluable; mixed feeding proved necessary, so I was spared the three in the morning feed. Feeding them one under each arm, rugby ball style, worked best for me, but was a very difficult skill to acquire.

It's possible to follow breast with bottle immediately, but the bottles have to be in place; it is unbelievable how many bottles need to be prepared every day!

When it came to feeding them solids I sat them side by side in chairs facing me and went from mouth to mouth using the same spoon; I calculated that they would be sharing the same germs anyway. It's an important thing is to get them into the routine of going to sleep at the same time; we started putting them together in a Moses basket, then two cots and finally two beds, although it's not unusual for Daniel to slip in with Ilana some nights.

To preserve sanity one must get out of the house regularly, and it is important to have two sets of everything ready by the front door so that nothing is forgotten; two baby car seats become very heavy as twins grow. The choice of twin buggy is important,

so that they can lie at first and sit up later. The supermarket tour can be very lengthy if you stop to answer every question; I have always dressed them differently, so pink and blue answered one of them. Was I insured 'against' twins? It was a bit late to learn that there is modest sum – about enough for one-and-a-half week's supply of nappies – available if you haven't had fertility treatment or a scan when you insure.

At first I was reluctant to ask for help, and my partner's redundancy was a godsend; my parents have been a great help since I took up their suggestion to move house close to them. A live-in maternity nurse can be a boon, and there are nannies; the advice supplied by the twins charities is largely aimed at the care of the twins ad their development, and what I needed was someone to help in the house and do the shopping.

When they started to walk they would want to go off in different directions, so it was necessary to limit their freedom, and generally try to be fair to them; it takes two adults to takes twins swimming, luck to keep them safe on bikes, and more space in Mothercare for a twins buggy. To preserve the individuality of twins parents have to make a great effort to celebrate their similarities and their differences, and while I recognise the importance of spending one on one time with them, time is limited, and we want to be together as a family. At birthdays the separateness of cakes and presents has to be preserved; asserting their independence as toddlers can lead to dangerous excursions which would be no problem with a singleton.

It is important at nurseries and schools that twins are treated as individuals and not as one unit; for them and for us the most satisfactory solution has been for them to be in separate classes in the same nursery.

“Twins are an instant family – just add milk”. It is a joy to watch their personalities develop, the interaction, the sharing which is unavoidable, and to experience the simultaneous welcome when you get home and the great sense of achievement. They get each other's help and encouragement.

Being a doctor is an advantage for me: I know what is normal and which specialist to turn to, have some first aid skills and time management. On the other hand I know too much – every rash may be meningitis or leukaemia, and I'm expected to be able to cope. Nonetheless I value the sources of advice available (see above for the MBA and TAMBA web sites); the TAMBA Twinline 0800 138 0509 operates from 10 a.m. to 1 p.m. and from 7 p.m. to 10 p.m. every day, all year round. And being able to talk to other mothers with twins at Twins Clubs is a blessing. The other necessities for the owners of twins are your parents near by, personal strength, the essential equipment, and a good sense of humour.

Reference: Dr. Carol Cooper (assisted by TAMBA) TWINS AND MULTIPLE BIRTHS The essential parenting guide from pregnancy to adulthood (Revised Edition 2004) Publisher: Vermilion


CR: With a 10% chance of conceiving twins again I won't be rushing into another pregnancy soon; even a singleton might be too much of a handful.

A delegate with twins reported being buttonholed for ten minutes in M&S by another mother of twins, who ended up by saying “And you know what – I bet people always stop to talk to you in supermarkets“.

A delegate suggested a flag on the supermarket trolley with the message “Yes I know they're identical – don't ask”. CR: Tesco no longer have trolleys for twins, and the twins were always running in opposite directions, so I'm shopping much more on the internet.

A delegate reported the mother of triplets who placed a box on her supermarket trolley with a sign “No questions without donations”. This put a stop to all questions. CR: There was a mother whom I met through a Twins Club who had triplets, two boys and a much smaller girl. She was always being stopped and asked “They're twins, but who is she?”. But it was for other reasons that I realised that my life with twins was much easier than hers.