Multiple Births
Twins and Multiples: The joys and the pain
In the UK approximately 98.5% of all multiple births are twins and about 33.3% of them are “identical” with the remaining being “non-identical”.
The causes of births of Identical (monozygotic) twins is still unknown however infertility treatment, parity (number of previous pregnancies), the height, weight, race and age of the mother and maternal family history of twins are the main factors associated with the birth of non-identical (dizygotic twins).
About 1 in 65 pregnancies in UK today is a twin
1 in 80 naturally conceived births in UK are multiples.
UK Statistics Twins and triplets– 2009 from: www.multiplebirths.org.uk
Average pregnancy length Average Birth Weight
Single – 40 weeks 3.5 kg/7lb 7oz
Twins – 37 weeks 2.5kg/5ln 5oz
Triplets – 34 weeks 1.8kg/3lb 9oz
Quads – 32 weeks 1.4kg/3lb1oz
No of births – England and Wales
All maternities 781,000
Twins 12,595
Triplets 172
Quads + 5
All multiples 12772
Multiple birth rate 16.3 (per 1000 maternities)
Multiple births used to be a rare sight until 1980 when twin births rose by 62%. Multiple births have risen even further since 1990 however since 1998 there has been a decline of 21% in the rate of higher-order multiple births.
Statistics now show that each year over 12,500 sets of twins are born in the UK.
Fertility and Conception
Researchers believe the increase in multiple births is linked to fertility treatments such as IVF and fertility drugs, and women putting off having families until they are older because of career or financial reasons. In fact, a recent study suggests approximately 80% of the births of triplets in 1996 and 1997 were as a result of fertility treatments.
The causes of births of identical twins is still unknown however infertility treatment, parity(number of previous pregnancies), the height, weight, race and age of the mother and maternal family history of twins are the main factors associated with the birth of non-identical twins.
It is well documented that Black Africans have the highest rate of giving birth to non-identical twins whilst Oriental women have the lowest; and that women 30 yrs old and over are more likely than younger women to have a multiple birth, even without the use of fertility treatment; this increases for women over 45 years old. Also, if the mother is a fraternal twin then the likelihood of her having twins increases four-fold and obese or taller than average women are more likely to have multiple births.
Scientists speculate that diet plays an important role in the conception of twins and that eating yams could affect a woman’s chances of conceiving twins, and consumption of dairy products could increase this possibility five-fold. They also suggest that there is a link between the number of daylight hours and conception of multiple births.
Fertility treatment however increases the chances of conceiving multiples to 1 in 4 from 1 in 60 (natural conception of fraternal twins), and from 3% for natural conception of any multiple. Inadvertently increasing the need for closer monitoring as women carrying multiples have increased risks during their pregnancy, the greater the number of babies the higher the risk to both mother and baby.
Risks and Mortality
Mothers having a multiple birth are monitored very closely throughout their pregancy for reasons of increased risks both to the mother and the babies.
Mothers are at increased risk of developing pre-eclampsia, high blood pressure, oedema and gestational diabetes, risks of hemorrhaging in the last 3 months of pregnancy or after labour, excessive vomiting during their pregnancy, premature separation of placenta, cord entanglement and cord prolapse are also increased.
Babies have an increased risk of growing poorly and developing serious health problems in the womb, being born prematurely, with low birth weight and at increased risk of mental retardation, cerebral palsy, and vision and hearing problems or possibly death due to the decrease in the average length of pregnancies.
Identical twins have a higher mortality rate than non-identical twins with 40% to 60% of conjoined twins being stillborn and 35% of the survivors dying after only one day.
Monitoring and Ultrasound Scans
Such high risk pregnancies require close monitoring as early diagnosis of complications and proper management is the best protection for mother and baby.
Regular ultrasound scans are often recommended, starting as early as 20 weeks to ensure all the babies are growing at the same rate and to detect possible problems with the placenta or blood circulation.
Ultrasound scans, however, should not be limited to checking on your baby’s growth as parents and siblings can derive pleasure from seeing the yet unborn addition to their family moving about in the womb instead of just feeling their movements. Now parents have the option of having 3d ultrasound scans and 4d ultrasound scans.
Having a baby scan in your special album or as your screensaver on your computer is also a wonderful memento for any parent but can you imagine the joy of real time video, produced by the 4d ultrasound scan that you could play over and over. How wonderful is that?
