Multiple births bring a new dimension to pregnancy and childbirth and parenthood.
A multiple birth is when two or more babies are born within the same pregnancy. The increasing use of fertility drugs has contributed to the incidence of multiple birth with more than half the triplets born resulting from assisted conception techniques such as IVF or GIFT (see Assisted Conception for more information on these methods).
In 2000, 245,700 babies were born in Australia and of these, 3,900 mothers had a multiple birth, constituting 1.6% of all births. This compares with 2,200 multiple birth recorded in 1980.
Of the 3,900 mothers who had a multiple birth in 2000, 3,800 of these produced twins with the remaining 100 resulting in triplets or higher order multiple births.
How Twins Are Formed
There are two ways that twins are formed:
Non-Identical Twins
Fraternal twins occur when a woman releases two (or more) ripe eggs that are fertilised independently by different sperm. If both eggs implant and grow in the womb, the babies will be fraternal twins. Because the eggs have been fertilised by different sperm, they can be different sexes and very different in character. They are referred to as dizygotic twins and account for about 80 per cent of twins.
Identical Twins
Monozygotic, or identical twinning, is less common. This occurs when a single fertilised egg divides into separate halves and continues to develop into two separate but identical babies. Identical twinning often occurs after fertilisation, and often after implantation in the uterus. Although they share the same placenta, they have their own amniotic cavity and own cord. Identical twins are always the same sex because they have been fertilised by the same sperm.
Some women suspect quite early in their pregnancy that they are carrying twins. If you are a fraternal twin, the likelihood of you giving birth to fraternal twins is almost twice as high as other women, though often it skips a generation.
Possible Implications
For many women, particularly first time mothers, the news of a multiple pregnancy is a shock.
The apprehension of being able to cope with one baby is suddenly increased. For those already with children, the prospect of two new babies can be daunting. If it is possible, it is a good idea to arrange help for the first few months.
Carrying more than one baby does have its difficulties. A multiple pregnancy is considered high risk and involves more antenatal visits and closer monitoring. Though as the figures above suggest, many multiple births occur in Australia without problems and multiple pregnancies do better than ever before. With the access to advanced methods of testing and scanning many of the problems can be detected and helped.
Morning sickness may be more severe and may continue for longer during multiple pregnancy. You will also be prone to anaemia caused by an iron deficiency because of extra demands on your supplies. Your doctor will usually prescribe extra iron and folic acid.
Obstetricians and midwives usually advise hospital births for multiple pregnancies as the chance of a complicated delivery are increased. The risk of developing Pre-Eclampsia is also higher as multiple pregnancies place extra strain on your body’s resources at an earlier stage of pregnancy so you are more likely to suffer from extra weight gain and higher blood pressure.
There is no doubt that a multiple birth puts greater stress on both the mother and babies and that problems are more likely because of this.
Most multiple pregnancies do not reach the 40 week full term and the possibility of premature labour increases from 20 weeks.
With twins, you can probably expect to go into labour between 34 and 38 weeks. With triplets, it is likely to be between 32 and 36 weeks.
Often the babies grow more slowly in the womb and are smaller than normal at birth due to the lack of space. Termed Intra-uterine growth retardation (IUGR) these babies are likely to be affected by the stress of labour, to breathe poorly, to suckle poorly, and to suffer from a severe lack of oxygen in labour. It is common for one baby to be bigger and stronger than the other.
There is a higher than normal risk of stillbirth and sometimes only one baby survives. A vaginal birth is more complicated with two babies carrying the risk of one getting tangled up with the other, or obstructing the birth canal, and often one is positioned in the breech position. In many cases a caesarean section may be necessary.
Adequate rest is important in multiple pregnancy. You will often feel better if you have regular rest times and go to bed early. Nutrition is also vitally important. Your placenta is providing for two or more babies and everything you eat counts. If you are not eating adequately, strain will be placed on both you and your babies.
The latter stages of pregnancy will be more taxing as extra pressure is placed on your digestive organs, your back, your diaphragm and lungs, making breathing more difficult. Less oxygen will make you feel fatigued.
You are more likely to experience varicose veins and piles because of the extra pressure on your circulation. Avoid standing for long periods of time and try to get regular, gentle exercise.
You may find it uncomfortable to lie flat as your heavy womb is pressing on major blood vessels. The best position is to lie propped up with pillows under your knees, or to lie to the side with pillows under head, your bump and upper legs to release the lower spine.
Pelvic floor toning is important throughout your pregnancy. Start early as muscle toning is more effective before there is undue strain placed on the muscles. Try some Pelvic Floor Exercises