What is multiple pregnancy?
The term multiple pregnancy is used to describe the development of more than baby in the uterus. Twins are the most common.
There are two types of twin pregnancy:
· Monozygotic or uniovular. ‘Identical twins’.
One egg is fertilised which later splits. This is usually into two, leading to monozygotic or identical twins, but there have been reported cases of monozygotic triplets and quadruplets. The babies are always of the same sex.
· Dizygotic or binovular. ‘Fraternal’ or ‘non-identical twins’.
More than one egg is fertilised at the same time. The babies can be the same or different sexes and are no more alike than any brother or sister
Higher multiples (triplets or more) can be all identical, all fraternal or a combination of both.
Why does multiple pregnancy occur?
Identical twins are a “freak of nature”. Every woman has an equal chance of conceiving identical twins, which is about one in 300 and is the same across all racial groups.
Non-identical twins are much more common, occurring approximately once in every 80 pregnancies in the UK. There is, however, a very wide geographical variation in the incidence of twins, with rates of one in 20 in parts of Africa and one in 200 in Japan. It is known that you are more likely to conceive non-identical twins if you are in your late 30’s, and have several other children. This is the type of twins that ‘runs in families’.
Am I going to have a difficult pregnancy?
Although many of the minor problems of pregnancy are exaggerated in a multiple pregnancy, this does not necessarily mean that your pregnancy will be difficult. You will, however, almost certainly become very tired as pregnancy progresses. There is also an increased risk of anaemia and hypertension. Recent research has also shown that it is especially important that you do not smoke during a multiple pregnancy.
Multiple pregnancy is often regarded as a ‘high risk pregnancy’, so you may find that you
need more antenatal checks than if you were carrying one baby.
The average length of a twin pregnancy is 37 weeks, for triplets it is 34 weeks and for quads, 33 weeks.
Will I be able to deliver normally?
How your babies will be delivered depends on a number of factors, such as the length of gestation and how the babies are lying. If you are expecting twins, a normal delivery may be possible provided the first baby is presenting headfirst. Make sure you discuss delivery with your consultant early on and let him know what your preferences are. If you are expecting triplets or more, delivery will almost certainly be by caesarean section
If your babies are preterm, be prepared for them to spend some time in the special care baby unit following delivery. Most hospitals will be pleased to let you visit the unit and meet the staff prior to the birth.
What about feeding the babies?
It is perfectly possible to breastfeed twins: in fact, if you are not going to have anyone to help you after the birth, it is probably easier than bottlefeeding. Whilst it is obviously more difficult to breastfeed triplets or quadruplets, many women do manage to breastfeed at least part of the time.