You may be wondering what are the chances of conceiving twins. triplets or more and can you increase the odds ?
The odds of having multiples are influenced by many factors. and twinning rates have changed throughout the years due to some of those factors. It's interesting to analyze the statistics and to consider you odds for winning the multiples lottery. So. are you a candidate for twins. triplets. quads or even quints ?
General Statistics About Multiples
Among the UK population. the chances of having twins in the 21st century are about 1.5 in 100. or about 1.5%. Your chances are better than ever; researchers have recorded an increase of nearly 50% since the early 1980s. The most recent statistics in 2004 show that twins. triplets and quads represented 14.87 of every 1.000 births or 1 in 67 pregnancies was a multiple birth (or 1 in every 34 children is a twin/triplet).
Increase or Decrease Your Chances of Having Twins/Multiples
You'll increase your odds of having twins/multiples if....
Maternal Age : You (the mother) are over age 35. The chances of having twins increases with age; in the 2004 UK statistics. the twinning rate of mothers over the age of 35 is 21.7 per 1000 maternities and becoming a mother after age 45 boosts your odds considerably to 56.7 per 1000 !
Assisted Conception : You take fertility drugs or undergo other fertility treatments. No one can deny that the availability of fertility enhancements has increased the multiple birth rate and on average the chances of having a multiple birth after fertility enhancing treatment is around 25% although you need to account for the fact that some fertility treatments have odds of only 20% chance of becoming pregnant.
Maternal History : You. your mother. or her mother's mother is a fraternal twin. These women may carry a gene for hyperovulation. which means they release more than one egg during an ovulation cycle. increasing their ability to conceive fraternal twins. The chances may increase if the mother is a fraternal twin herself.
Previous Pregancies : You've already had one set of fraternal twins. For mothers who have already had one set of fraternal twins. their chances of conceiving another set are five times greater than the average woman. or about 1 in 14 ! Women who have had more than four previous pregnancies are also more likely to conceive twins.
Race : You're Nigerian. This African country purportedly has the highest twinning rate in the world. estimated at around 1 in 20. Some sources attribute it to their consumption of large quantities of yams. (It's worth a try if you really want to have multiples!)
You're overweight or tall. A recent 2005 study published by the American College of Obstetrics and Gynecology reported a significant increase in fraternal twin births to mothers who had a BMI of 30 or higher. or who were in the top 25th percentile for height.
You'll decrease your odds of having twins/multiples if...
Race : You (the mother) are Asian. Among worldwide populations. the Asian countries of Japan and China have the lowest twinning rates. estimated at 1 in 150 and 1 in 300. respectively.
Age : You (the mother) are under age 25. The chance that a woman would bear twins before her 25th birthday are is less than half of what it would be after age 35. The Uk 2004 statistics showed the twinning rate to be only 6.3 per 1000 for the under 20s compared to the average of 14.87 for the total population.
Zygosity : You're looking for identical multiples. The rate for identical. or monozygotic. multiples is random and universal; it's the same in all populations regardless of race. heredity or other factors. and it has remained constant over time. The chances of having identical twins is about 1 in 285.
Odds of Triplets. Quadruplets &; Higher Order Multiples
The statistics for higher order multiples in the UK have shown a dramatic decrease in recent years. The odds of conceiving triplets is about 1 in 4.400. In the UK. there has been a substantial decrease in the rate of triplet births over the last few years. (Triplet births peaked in 1998 with 297 sets born in the UK). primarily due to the HFEA regulations limiting the number of embryos that can be transplanted since 2001.
The odds of having quads is currently 1 in 142.000 (latest statistics show there& ;were 5 sets born in the UK in 2004) but for spontaneous quadruplets (non-assisted) the chances are predicted to be 1 in 729.000.
There have been no sets of quintuplets born in the UK since 2002 where there were 2 sets born and the last set of sextuplets that was born was in 1993.
It is estimated that 60% of triplets are the result of fertility enhancing treatments; while 90% of quadruplets are due to reproductive technology.