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Back to. Image credit: CDC As of , there are on average around 16 sets of twins born per 1, births in the United States. There are two types of twins Identical twins Identical twins come from a single egg that was fertilized by a single sperm, which then divided into two separate embryos very early in the pregnancy.
They are no more related than regular siblings! Image from Wikimedia Are there factors that increase your odds of having identical twins? Are there factors that increase your odds of having fraternal twins?
There are several things that can increase the odds of fraternal twins. Everyone has a chance of having twins. More Information WA state twin registry: Twins run in my family. Below are a few that are especially relevant to this article: : Twins seem to run in my family.
Does it have to do with our genetics? Is this true? Do scientists know why this is? Does this increase our chances of having twins? References Hoekstra, Chantal et al. Steinman, G.
There were approximately , twin births out of 3. This was a 2 percent decline from and a 5 percent decline from Meanwhile, there were about 88 sets of triplets and higher-order multiples per , births — a 6 percent decline from Although the twin birth rate rose by 76 percent between and , it declined 4 percent between and — the lowest rate in more than a decade.
For women age 30 to 34, the twin birth rate declined by 10 percent; 12 percent for women age 35 to 39; and 23 percent for women age 40 and over. It's possible that the birth rate for twins has slowed down because fertility treatments have improved.
For example, with in vitro fertilizations IVF , doctors would usually transfer multiple embryos into the uterus at once to increase the chances of having one successful pregnancy. This also raises the likelihood of twins, but now doctors are transferring just one or, rarely, two embryos at a time to reduce high-risk pregnancies.
That's because women who have a multiple pregnancy carrying more than one baby are at a higher risk for complications, including preterm birth, low birth weight, preeclampsia high blood pressure , gestational diabetes, and a cesarean birth. Although the birth rate for triplets and higher-order multiples had quadrupled between and , it declined by 6 percent in and was down 55 percent from the peak in The number of triplet and multiple births was 3,, which is the lowest number reported since It's also less than half of 7, — the highest number of triplet and higher-order multiple births ever reported in Similar to twin births, the slowdown in triplet and higher-order multiple births is likely due to the improvements in fertility treatments.
About 20 years ago, fertility specialists would transfer four embryos routinely for women of all ages, but now women are getting, on average, half as many embryos transferred at one time.
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This educational content is not medical or diagnostic advice. Use of this site is subject to our terms of use and privacy policy. Registry Builder New. Wondering what the odds of conceiving twins are? Conception happens when a sperm fertilizes an egg to form an embryo. However, if there are two eggs present in the womb at the time of fertilization or the fertilized egg splits into two separate embryos, a woman can become pregnant with twins.
Twins are relatively uncommon. However, the birth of twins has increased significantly alongside the rise in the use of fertility treatments and with more women choosing to have children at a later age. Since , the birth rate of twins has increased by more than 75 percent.
A woman is more likely to have fraternal twins than identical twins. Identical twins account for only about one-third of multiple pregnancies. A woman has a slightly higher chance of having twins if she has a family history of twins.
However, this only applies if conception takes place without the use of fertility treatments. According to the ASRM , women who are themselves nonidentical twins produce twins in around 1 in every 60 births. For men who are nonidentical twins, the chance of conceiving twins is only 1 in every births.
Some people believe that twins can skip a generation, meaning that a person will potentially have twins if one of their grandparents did. However, there is little evidence to support this theory. The ASRM note that the main factor that increases the chance of having twins is the use of fertility treatments.
The various types of fertility treatment available increase the likelihood of twins in different ways. If sperm fertilizes both of these eggs, this can result in twins. To increase the likelihood of success, the healthcare professional may place more than one embryo into the womb. Twins can occur if both embryos implant and develop successfully.
The reason for this is that women of this age are more likely than younger women to release more than one egg during their reproductive cycle.
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