Jane Denton, director of The Multiple Births Foundation and a midwife, answers your most frequently asked questions about twins and multiple births.
Q: How do I know if my twins are identical?
A: Finding out whether twins, triplets or more are identical is known as zygosity determination. A zygote is a very early fertilised egg. There are two types of twins.
- Dizygotic (also known as non-identical or fraternal) twins arise from two, separate, fertilised eggs. These babies will each have a placenta and one outer sac (chorion) and one inner sac (amnion). This will be written in your notes as DCDA (dichorionic diamniotic). These babies will be no more genetically alike than other brothers and sisters, and could be either the same sex or boys and girls.
- Monozygotic (also known as identical) twins arise when one fertilised egg splits. The babies then have the same genes. If you are having triplets or more, they can be all identical, or a mixture of identical and non-identical ??ask your midwife to explain the code that has been written in your notes.
Q: Do identical twins share a placenta?
A: That depends on when the fertilised egg splits.
- If the zygote splits in the first four days after fertilisation, each baby will have a placenta and separate outer sac (chorion) and inner sac (amnion). This happens in about one third of cases with identical twins. Even these days, some women are told that if there are two placentas the babies cannot be identical which isn't the case. This will also be written in your notes as DCDA.
- If the zygote splits later, there will be one placenta, one outer sac (chorion) but two inner sacs (amnions). You may see MC (monochorionic) DA (diamniotic) written in your notes.
- If the zygote divides after about 12 days, the babies will also share one inner sac, which is referred to as monoamniotic (MA). As this occurs in only about 1% of identical twins it's quite rare.
Q: Is it important to know whether my twins are identical, or whether they share a placenta or a sac?
A: It is important that doctors find out your babies' 'chorionicity' (whether they share a chorionic sac or have their own) and whether they share a placenta. The sacs can be seen in the early 10-14 week scan. If you know you're having more than one baby, ask the operator to look at the sacs. This will usually be established at your first scan as it is easier to assess before about 12 weeks of the pregnancy. If the babies share one placenta, your pregnancy will be more closely monitored.
You'll probably be referred to a regional fetal medicine centre for an assessment as sometimes these babies can develop a condition known as twin to twin transfusion syndrome (TTT) if the blood flow between them becomes unbalanced. The staff in fetal medicine centres have specialist expertise in managing these pregnancies.
If you're still not sure about zygosity after the babies are born, but want to know for sure whether they're fraternal or identical, you can have a DNA test in a specialist laboratory. This costs between 瞿150 and 瞿200, and you can find clinics through TAMBA, the Multiple Births Foundation, or by looking on the internet.
Q: When should I start antenatal classes?
A: Twins, triplets and more are much more likely to be born earlier than single babies. About half of twins, for example, are delivered before 37 weeks. So with more than one baby, it's advisable to start classes at about 24 weeks.
Q: Will I be able to have a normal delivery?
A: In theory yes, but you, your midwife and doctor will want to take several things into account before finally deciding. These include the duration of the pregnancy, the position of the babies in the womb and the chorionicity. Caesarean section is much more common in twins or more, because of the possible complications.
One of the main considerations will be the position of the babies. If they're lying head down, which happens with about 40% of twins, they may be delivered normally. If the babies are bottom first (breech) or lying across the womb (transverse) it's likely your midwife and doctor will suggest a caesarean. Although many twins will arrive early spontaneously, an elective caesarean would usually be planned for 37-38 weeks.
If the twins share a placenta (monochorionic), a caesarean may be planned for about 36 weeks. Your midwife and doctor will discuss all of this with you and help you make the best decision for you.
If you're having triplets or more, you're likely to have an elective caesarean.
Q: Is it possible to breastfeed twins?
A: It's perfectly possible to breastfeed twins and more, and many mothers do so very successfully. Others combine breast milk and formula and some may choose to use just formula. Whichever method you choose, it's important that it suits you and your babies.
Your decision will also depend on whether your babies were born earlier and with a lower birth weight than single babies. If so, you may need to express milk to bottle-feed them if they're not able to suck at the breast.
The most important thing is to have all the information you need before making the decision. More information about feeding twins, triplets and more is available from the Multiple Births Foundation and TAMBA.
Q: Spending time in special care
The chance of one or more of your babies having to be in the Neonatal Intensive Care Unit (NICU). According to a TAMBA (Twins and Multiple Births Association), around 40% of twins and 97% of triplets go into special care. The reasons they're there will dictate how much you can touch and hold them, but you will be able to be with them as often as you want. Ask to have their beds put near each other so that you can easily see all your babies.
It's not easy if one or more of your babies goes into special care but another doesn't. It can be especially difficult if one baby is particularly sick and needs to be in a different hospital altogether. You will understandably feel torn between them.
If your well baby is in the same hospital, ask if she can be moved nearer the NICU?so it's easy for you to pop out and see her. Or take her with you when you go to visit her sicker brother or sister. But if none of this is possible, try to reassure yourself that your sicker baby needs more of your care and attention, and ask your partner or parents to be with the well baby.
Q: Can the babies sleep together?
A: Yes they can, but a lot depends on your own personal circumstances ??for example how much space you have in your bedroom.
Many twins and triplets sleep in the same bed in the early months of life and there is no evidence to suggest that there are dangers. Whatever you decide you should always follow the Department of Health advice on reducing the risk of cot death, about sleeping positions and sharing your bedroom (see feature on safety).
If the babies are together in one cot, it may be that you can keep them in your room for longer. Other advantages are that the babies are more likely to wake at the same time and provide support for each other. This can help establish a good sleep routine earlier. Surprisingly, the babies disturb each other much less than many parents expect.
With quads or more, you might be able to put them down to sleep in the same cot depending on how big it is, but two each in two cots would be a good compromise.
Q: I'm having quads - what help will I get?
A: Unfortunately, much to the surprise of many people, there is no additional financial or practical help available from the state on a routine basis for parents with twins, triplets or more.
However, help is very important and parents are advised to plan this as soon as possible.
- If relatives or friends are offering to be involved, you should make sure they are able to fulfill whatever commitment they make if you're relying on them for regular support.
- Students on the Diploma in Child Care and Education courses at local colleges are often pleased to have work experience with twins and more.
- If you can afford to pay for help, think about the kind of help you want. Mother's help or au pairs can lend a hand with household tasks as well as looking after the babies, whereas maternity nurses and nannies focus on childcare.
Q: I'm pregnant with triplets - can I be screened for Down's syndrome?
A: You can have the nuchal translucency ultrasound screening test.