There's something fascinating about twins. You can't help but wonder what it's like to grow up with an instant companion who looks exactly (or very similar) to you. While there are more twins living now than ever before, they're still quite unique.
There are a lot of things you may not know about twins, including what type of woman is most likely to conceive them and how the babies interact with each other when they're still in the womb. Read on for some fascinating facts about twins...
A Woman's Age & Diet Can Increase The Odds Of Conceiving Twins
If you really want twins, there are a few things you can do to increase the odds. You're already ahead if you're a twin yourself because fraternal twins are four times more likely to give birth to twins. Also, if you're over 30, you're more likely to release more than one egg during ovulation, which increases your chances of having twins.
Women who are breastfeeding when they get pregnant are nine times more likely to conceive twins. Also, mothers to be who include dairy in their diet are more likely to have twins, when compared to vegans.
25 Percent Of Twins Are Mirror-Image Twins & They Have A Higher Chance Of Left-Handedness
About one-quarter of identical twins are known as "mirror image twins." This means that they are exact reflections of each other. That means one twin may have a mole under her right eye, while her sister will have a mole under her left eye.
Another interesting fact is that twins have a higher chance of being left-handed. In the general population, about 10 percent of people are left-handed. Among twins, 22 percent are left-handed.
A Test May Be Required To Identify Identical Versus Fraternal Twins
Obviously, if a mother is pregnant with a son and a daughter they are fraternal twins. If the twins share a placenta and amniotic sac they are identical (the exception is if there are two placentas fused together). So, a mother may have to wait until the babies are born to learn what type of twins she's having.
It's not uncommon for fraternal twins to look alike, so genetic testing comes into play. With a simple swab of the cheeks, new parents can get confirmation about the nature of their twins.
Identical Twins Have Nearly Identical DNA, But Their Fingerprints Are Different
Identical twins share a lot of things. In addition to looking exactly alike, they have nearly the exact same brain wave patterns (and thus, are on the same wavelength). In addition, their DNA is 99.9 percent the same.
However, not everything about identical twins matches. They do not have identical fingerprints or teeth marks. So, if one twin carries out a crime (or dies), it is easier to identify him or her using dental records or by checking their fingerprints.
New Parents To Twins Fear They Won't Be Able To Tell Their Children Apart
The challenges related to twins are double that of having one newborn. And one of the problems that many parents face is trying to tell the difference between their identical babies. This is particularly difficult if neither baby has a distinguishing feature, such as a mole.
To make things easier, some moms or dads will actually paint one of their infant's toenails to tell them apart. Or they will dress them in certain colors. Fortunately, once the umbilical cord falls off, the difference is obvious because belly buttons are so unique.
Some Infants Absorb Their Twin In Utero
While approximately one in eight pregnancies will start with twins, only one in 70 results in twins. This is due to "vanishing twin syndrome" in which one of the babies doesn't live. This typically happens fairly early in a woman's pregnancy.
In this situation, the mother's body or the surviving twin absorbs the embryo. There are usually no complications when this occurs, though we can't help but wonder if the surviving twin feels like something is missing later in life.
Not All Twins Have The Same Birthday
Typically, twins are born on the same day. If they arrive via a C-section, they are usually born a minute or two apart as the doctor removes them from the mother's womb. They may be born as much as an hour apart if the mother gives birth naturally.
However, some births occur near midnight, and one baby is born on one day and the other baby is born on the next. In addition, there may be some medical intervention that necessitates delaying the birth of one of the babies.
It's All About The Timing
Twins occur when one egg splits post-fertilization. However, it's not as simple as that. The timing of the split plays a very important role. For example, if the twins have their own sacs and placentas, which occurs on day one through three, then they are di/di twins.
If they share a placenta, which occurs on days four through eight, they are mo/di twins. Twins that share both an amniotic sac and placenta are mo/mo twins (day eight through 13), while conjoined twins have an egg that splits on day 13 to 15.
A Lot Of Twins Are Born In Nigeria (And Massachusetts)
The country with the highest rate of multiple births is Nigeria on the Gulf of Guinea in West Africa. Approximately four percent of the births in Nigeria are twins. Igbo-Ora is known as the "Twins Capital of the World." Scientists believe it's due to the genes that have passed on from generation to generation.
Meanwhile, in the United States, more twins are born in Massachusetts than any other state at about 4.5 per 100 births. The U.S. national average is three percent.
There Are More Twins Now Than Ever Before
The rate of twins has increased 76 percent since 1980, according to the CDC. In 2009, one in every 30 babies was born a twin versus one in every 53 in 1980. One reason is that the average age of mothers has increased, and as we mentioned earlier, older women are more likely to have twins.
Also, there has been an increase in fertility treatments, which has largely contributed to the birth of multiples. Unfortunately, twins are more likely to be born at low birth weights and can have additional health problems such as asthma.
Taller Women Are More Likely To Have Twins
Taller women have more insulin-like growth factor (IGF), according to Gary Steinman, MD, Ph.D., an attending physician at Long Island Jewish Medical Center. This protein is released from the liver due to a growth hormone. Higher levels of IGF cause more sensitivity in the ovaries.
This, in turn, increases a woman's chance of ovulating. The more IGF a woman possesses, the higher the odds that she will have twins because IGF increases the rate of spontaneous twinning, according to Steinman.
Many Twins Develop Their Own Language
About 40 percent of twins concoct their own language. However, this type of communication isn't limited to twins. It also occurs among non-twin babies around the same age that spend a lot of time together while they're simultaneously learning language skills.
Typically, the made-up language falls by the wayside after the babies start learning a real language. Once they learn how to communicate with others, such as mom and dad, they no longer need to use their invented form of communication.
Moms Of Twins May Live Longer
Women who have twins tend to be healthy and strong and are more likely to live long lives, according to a study published in the journal Proceedings of the Royal Society that concentrated on a population of women in 19th-century Utah. Essentially, twins could be evolution's way of passing healthy genes in a double dose.
This data, however, only relates to women who naturally conceive twins. During the 1800s in vitro fertilization (IVF) was obviously not a factor, and the findings are not conclusive.
Several Celebrities Have Twin Siblings You May Not Know About
The King of Rock and Roll, Elvis Presley, had a twin brother who was stillborn, and actor Ashton Kutcher has a fraternal twin brother with cerebral palsy. Actress Scarlett Johansson has a twin brother, and actor Kiefer Sutherland has a twin sister. Supermodel Gisele Bündchen has a fraternal twin sister.
Jon Heder of Napoleon Dynamite fame has an identical twin brother, while actress Isabella Rossellini has a fraternal twin sister. Actor Vin Diesel and singer Alanis Morissette also have twin brothers. Did you know so many famous people had twins?
Twins Bond In The Womb
A 2011 study by Italian researchers at Umberto Castiello of the University of Padova examined 3D videos of twins in the womb. It found that twins started reaching for each other at 14 weeks of gestation. Just one month later, they start touching each other more than they touch themselves.
While analyzing the video, the researchers determined that the twins made obvious gestures towards one another and were even gentle with sensitive areas such as the eyes.
Twins Live Longer Than Singletons
Twins typically live longer than the general population, and identical twins tend to live longer than their fraternal twin counterparts, according to a 2016 study from the University of Washington.
Study author and postdoctoral researcher David Sharrow, Ph.D., carried out the research. He noted that twins have a built-in support system. They have someone who they are very close to who is always looking out for them. This emotional support can lead to a longer life.
Twins Don't Often Make It To Full Term
The best time to deliver twins is at 37 weeks of gestation (or 36 weeks if they share a placenta) to avoid stillbirth and other complications, according to the medical community. Typically, this occurs naturally and intervention isn't required.
The reason why twins don't reach 39 or 40 weeks full term is because the uterus stretches a lot earlier on in the pregnancy. As a result, twin pregnancies are more likely to result in pre-term labor, which occurs before 37 weeks.
The Odds Of Identical Twins Living Past 100 Is One In 700 Million
The odds of identical twins living past age 100 is one in 700 million. So, who are the oldest twins of all time? There have been reports that twins Eli and John Phipps lived until the ages of 108 and 113, respectively. They were reportedly born on February 14, 1803, in Virginia.
Eli and John's mother lived until the age of 93, and their father died at the age of 111. The siblings reportedly had little to no health issues, thus leading to their long lives.
Britain's Oldest Twin Sisters Credit Guinness & Lack Of Intimacy For Their Long Lives
Lilian Cox and Doris Hobday are 95 years old and the oldest identical living twins in the United Kingdom. In September 2019, they opened up about their lives and the reason why they believe they've lived so long. According to Lilian: no intimacy a" and plenty of Guinness."
Lilian does not have a husband, so she credited that fact to her long lifespan. The sisters live next door to each other and celebrated their birthday in July by creating social media profiles on Facebook, Instagram, and Twitter.
They Can Have Different Dads
There is a condition called heteropaternal superfecundation in which a woman can give birth to twins with different biological fathers. This type of condition is extremely rare. It happens when a woman releases more than one egg and is intimate with two different men while her fertility is at its peak.
The result is fraternal twins. There has been very little research about this phenomenon, and most cases only become publicized when someone has a question about paternity and a DNA test is performed.