…that I am kinda obsessed with twins? I know, I’m weird. Sometimes, when I should be studying (like now, for instance), I surf random facts about twins on the Internet. So just in case you were wondering, here are a few facts about twins:
- American women who put off their pregnancies until past their 30th birthday are increasing their chances of having multiples.
- Mirror-image twins occur only in identical twins. In approximately 23 percent of identical twins, the fertilized egg splits later than 7 days following conception. The original right half of the egg becomes one twin and the original left half becomes the other. These twins will often have “mirror images” of their features, such as hair whorls that run clockwise in one and counter-clockwise in the other, a birthmark on the right shoulder of one and the left shoulder of the other, etc. There is no specific test for determining if twins are mirror-image, however. The determination is made by observation only, and the twins must be mono-zygotic, or identical.
- 1 in 100 births is a twin.
- 1 in 250 births is an identical twin.
- The largest number of multiple births by one woman is 16 sets of twins, 7 sets of triplets, and 4 sets of quadruplets – 69 children born between 1725-1765 and 67 of which survived to adulthood.
- Twins births have risen 62% since 1980 (mostly due to interventional reproductive assistance and older age women having children)
- Nigeria has the highest twinning rate in the world, estimated at 1 in 22. Some sources attribute it to their consumption of large quantities of yams.
- For mothers who have already had one set of fraternal twins, their chances of conceiving another set are four times greater than the average woman, or about 1 in 12.
- Women who have had four or more previous pregnancies are the most likely to have twins.
- People of African American descent are more likely to have twins or multiple births. People of Asian or Hispanic descent are less likely to have twins.
- Having a maternal history of twins or other multiple births increases your chance of becoming pregnant with twins considerably.
- A 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.
- Twins have a higher rate of having twins themselves.
- If you are breastfeeding when you get pregnant that you are more likely to have twins. This is said to be caused by the depletion of calcium in your system while nursing and its effect on the egg during conception and ovulation.
- The odds of having spontaneous quadruplets are predicted to be 1 in 729,000.
- 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.
Alright, that’s it! I’ll just marry a Nigerian man with a history of multiples, eat some yams, gain some weight and wait until I am 30 to have kids!
