Twins, twins, triplets: interesting facts. Twins. The optimal time for childbirth How often twins are born among representatives of different countries and peoples

Oddly enough, multiple pregnancy is not such a rare occurrence. If they were collected from all over the world in one place, then this number could be the population of two Frances! More than 100 million twins live on earth, and in Moscow alone there are at least 70 thousand couples. For every 100 newborns, there are one or two twin pairs. The record number of twins is born in Africa (in some tribes, every twentieth birth is multiple), the smallest is among representatives of the Mongoloid race.

Moreover, the number of multiple pregnancies is increasing. The statistical likelihood of getting twins or even triplets has been on the rise in recent years. Ten years ago, it was about 1:85, and now for every fifty births there is one twin or triplet. The number of quadruplets also increased: for example, in Germany from 1950 to 1983, quadruplets were born only 19 times, and in five years from 1983 to 1989 there were already 56 of them. A clear upward trend!

There are two reasons for the increase in the number of multiple births: women between 35 and 40 years of age are always more likely to give birth to twins than women younger than 35. Why this is so is not known, but it is an undeniable fact that there are now many more “late mothers” than another twelve years ago. However, the most important reason for the increase in multiple pregnancies is infertility treatment. If ovulation is stimulated by medications, then two or more eggs mature at the same time, and then fertilized at once. An increase in the number of triplets or quadruplets can be associated with hormonal treatment with absolute certainty.

In the occurrence of multiple pregnancy, the role of heredity is beyond doubt. So, in 31 out of 300 women in labor with a history of twins, relatives had indications of multiple pregnancies. Multiple pregnancy - the simultaneous development of two or more fetuses (twins). Its frequency ranges from 0.4 to 1.6%, but in recent years these figures have been increasing due to the use of drugs that stimulate ovulation (clomiphene, pergonal, etc.). The likelihood of multiple pregnancy increases with the age of the mother. Pregnancy with twins is observed most often and is 1:90, the frequency of three twins increases to 1:902, four - up to 1:903. Boys predominate among born twins.

The frequency of twin births may be related to the affiliation of the spouses to a particular ethnic group. So, in China it is 3:1000 live births, in Scotland - 12.3:1000, in Nigeria - 57.2:1000. These differences are associated with fluctuations in the frequency of the birth of fraternal twins, since the birth of identical twins around the world is kept at about the same level (3.5: 1000).

With the development of ultrasound methods and their application to determine the state of pregnancy, it has become apparent that the frequency of multiple pregnancy in humans can be higher than the numbers just given indicate. In fact, the rate of multiple pregnancy in developed countries is as high as 20:1000 pregnancies. In about 50% of cases, multiple pregnancy is not recognized, the reason for this is the high frequency of spontaneous abortions in the early stages in some women and spontaneous resorption of one of the amnions in others.

According to various estimates, today in the world there are from 70 to 80 million pairs of twins.

The number of twins born in relation to the total number of newborns in different countries and on different continents is different, but in general the trend is such that it continues to grow. Compared with the 60s, the percentage of twins has increased from 1.18 to 2.78, that is, almost 2.5 times. Much is said about the reasons for this phenomenon, and among the main reasons are the successes of modern medicine in the field of infertility treatment. (For more on why, see Who gets twins and can I have twins?)

In the early 1980s, there was one twin for every 80-90 births.
In the late 1990s, there was one twin for every 40-45 births.

In the early 1980s, there were one triplets for every 6,400 births.
In the late 90s, there were one triplets for every 800-1300 births.

How often twins are born among representatives of different countries and peoples

European women 1 in every 69 births Black American women 1 in every 60 births Japanese women 1 in every 150 births Chinese women 1 in every 250 births Other Asian women 1 in every 125 births Nigerians 1 in every 22 births Norwegian, Danish and Dutch women 1 in every 49 births English women 1 for every 76 births

Who is more similar or different?

In the US, there are 1 pair of non-identical twins for every 100 people in the population.
and for every 300 people - 1 pair of identical twins.

1/3 of all twins born in the US are identical. In Japan, the proportion of identical twins is 2/3 of all twins.

According to the pattern derived by American scientists, the frequency of the birth of twins before the widespread use of new methods of treating infertility was as follows:

Twins 1 in 90 Triplets 1 in 8,100 Quadruples 1 in 729,000 Quintuples 1 in 65,610,000

Dear women! According to many studies, "twinhood" can be inherited (maternally). So, -
If you are a non-identical twin, you have about a 6 in 100 chance of having twins.
If you are an identical twin, you have exactly as many chances as any other woman (from 1 to 2.5 chances out of 100, depending on the use of hormonal drugs).
If your mother is a non-identical twin, your chances are above average.
If your father is a non-identical twin, then the chances are average, just like if your husband is a twin, or has twins in the pedigree.
If either of your parents is an identical twin, this will not affect your chances in any way.

Unfortunately, such data are extremely rare, so we are content with statistics for Canada and the United States.

Twins 1/3 boy-girl 1/3 boy/boy (about 50% identical, about 50% non-identical) 1/3 girl/girl (about 50% identical, about 50% non-identical) Triplets 18% boys only 21% girls only 61% 2 girls - 1 boy or 2 boys - 1 girl Fours 85% boys and girls in various combinations 5% boys only 10% girls only

Number of twins in a given country

Here, for example, statistics for 1997 in the UK:

A total of 718,997 births took place.

Twins 10,017 Triplets 321 Quadruples 9 Five babies 1 Total multiple births 10,348

In total, in the UK at the end of 1997 lived:

twins (2, 3 or more) under the age of 5 45,000 twins (2, 3 or more) under the age of 10 90,000 twins (2, 3 or more) under the age of 16 144,000

(Source: ONS London, GRO Scotland, GRO Northen Ireland)

Here's the data for the US:

1996 1997 1998 Twins 100 750 104 137 110 670 Triplets 5 298 6 148 6 919 Quadruples 560 510 627 Five or more 81 79 79 Total births 3 891 494 3 880 894 3 941 553

As the average age of women giving birth continues to increase (especially in developed countries), the likelihood of more twins being born is also increasing. In 1990, 39 women aged 45-49 in the United States became mothers of twins. In 1997, there were already 444. From 1980 to 1996, not a single woman aged 50-54 gave birth to twins. In 1997, 50 women of that age gave birth to twins and 13 to triplets.

But the main reason for the increase in the frequency of twin births continues to be the development of infertility treatments. Modern research shows that 80% of triplets were born as a result of the use of such methods.

The flip side of the increase in twin births is more underweight babies and preterm births, which in turn lead to higher infant mortality rates. In terms of statistics, the risk of premature birth and the birth of children of too small weight (before 1500) in the case of twins is 8 times higher, and with triplets 33 times higher than in the case of the birth of one child. In 1998, 41.7% of twins and 89.1% of triplets were born premature or very low birth weight.

(Trends in Twin and Triplet Births: 1980-98, by Joyce A. Martin, M.P.H. and Melissa M. Park, B.S. Division of Statistic)

The usual duration of pregnancy is 39-40 weeks, in the case of twins 36 weeks, with triplets 33-34 weeks, with quadruples 30 weeks, with quintuplets 28-29 weeks.

18-22% of twins are left-handed (in non-twins this percentage is 10).

Identical twins have similar encephalograms.

The science that studies twins is gemellology.

Often, twins talk to each other in a language that is not understandable to others. This phenomenon is called cryptophasia.

Yesterday, Beyoncé Knowles shared the good news with fans: the singer posted a photo with a rounded belly on Intagram and admitted to followers that she and Jay Z were expecting twins. Thus, very soon, baby Blue Ivy will have two brothers or sisters once. On this occasion, we have collected a few facts about twins that you may not have known.

Twins are born often

In 2014, the U.S. twin birth rate reached its highest ever, according to the Centers for Disease Control and Prevention. In Russia, in accordance with the data of the Social Insurance Fund of the Russian Federation, the birth rate of twins doubled from 2006 to 2012. And by 2014, it amounted to 18315 twin births per year.

At the same time, nationality matters here. Statistics show that Asian women have a negligible chance of giving birth to twins - they have twin births in 250 normal births. At the same time, in Nigeria, on average, every twenty-third new mothers have twins.

One of the possible reasons for the increase in the birth rate of twins in Europe, experts call the fact that women today are more effectively treated for infertility and more often use artificial insemination (IVF), which increases the likelihood of twins by several times. In addition, in today's world, women are increasingly having children at a later age, and this also increases their chances of twins, according to a number of studies.

Even identical twins are not the same

In fact, even identical twins have significant genetic differences. And while they start out with identical DNA, genetic changes can occur as early as the early stages of fetal development, according to a study presented at a meeting of the American Society for Human Genetics (ASHG). This fact may partly explain why some pairs of twins may develop differently over the course of their lives: for example, when one of them gets a chronic disease, while the other remains healthy.

Genes play a huge role here

The landmark Minnesota Twin Family Study, which examined pairs of identical and fraternal twins who were separated in infancy, found that even twins who had lived far apart for decades still shared an astounding number of traits - both medical and psychological.

These data testify to the strength of human genes. For example, twins who had never seen each other still assumed the same postures when sitting or standing, while twins in the same situation assumed different postures.

Here's a typical example: twin brothers Jim Lewis and Jim Springer were separated at 4 weeks old and reunited at 39 years old. The study found that they both suffer from headaches, bite their nails, smoke the same cigarettes and drive the same brand of car.

Gemini can live longer

Gemini, apparently, than men and women who are not twins. Studies conducted by Danish scientists have shown that identical twins, on average, really live 4-5 years longer than twins, and the life expectancy of twins is 2-3 years longer than that of ordinary children.

Family History Matters

The reason why some women have twins and others don't is because of the combination of two genes. This conclusion was recently reached by researchers from the Netherlands, who checked whether those women in whose family there were twins and twins are more likely to have two babies at once.

It turned out that two genes are responsible for this, and both of them play a role in the production and processing of follicle-stimulating hormone (FSH), which helps the eggs mature. One hormone is associated with higher levels of FSH, which increases the chances of two eggs maturing at once. Another hormone increases the egg's sensitivity to FSH, which also makes it more likely for two eggs to mature at the same time.

In ancient times, the appearance of two babies in a family at once was considered by some peoples as an omen of good luck, by others - tricks of evil spirits. The reasons for the appearance of twins in the family have already been studied in detail. Among the factors influencing multiple pregnancies are the age of the mother, nutrition, nationality, and more.

To be honest, as a child, I dreamed of twins. But knowing that such miracles did not happen in our family, we had to rely on only one baby. However, nature still gave me a surprise and now I am the mother of wonderful little boys. What is the mystery of the female body?

As a rule, during the period of the menstrual cycle, one egg matures in a woman, from which one child appears. In my case, two eggs matured during one cycle. After their fertilization and 9 months later, twins were born, only partially similar to each other. These are fraternal twins.

However, there are times when one already fertilized egg is divided into two parts in the early stages, in each of which separate organisms are formed. From these cells, absolutely identical twins are born. They are called monozygotic. The probability of having similar twins in the world is 0.3%.

DYNAMICS OF THE BIRTH OF TWINS IN THE RUSSIAN FEDERATION

Meanwhile, fraternal twins are no longer uncommon. In Russia, studies are constantly being conducted that show the dynamics of the birth of twins and triplets. Let's try to analyze the reasons for the appearance of twins in detail.

Heredity

The most significant factor. If in your family there were cases of the birth of twins, you can be a follower of this tradition. The chance of having twins increases through the generation. Simply put, my grandchildren are more likely to have twins than my children.

The condition of heredity applies only to fraternal twins. The birth of identical twins, even among the closest relatives, does not affect your chances in any way.

Age

I gave birth to my boys at 30. And statistics just show that it is at this age that the probability of giving birth to two children at once is 0.90%. By the age of 35, the chances of giving birth to twins increase by as much as 5.5 times to 1.48%. After this age, a gradual decline begins. As a result, by the age of 48, the chances of giving birth to twins are 0.30% (as in 18-year-old girls).

The reason for this age parabola lies in female physiology. With age, ovulation does not occur every month. As a result, unrealized hormones accumulate and are released during the next cycle, stimulating the release of several eggs.

childbirth

If you already have children, then with each subsequent birth, the probability of having twins doubles. For those mothers who already have twins, the likelihood of having another couple is very high.

Nationality

This phenomenon is little studied and still not understood, but the fact remains: if you are from Nigeria, then the probability of having twins is 10 times higher for you than, for example, for French women. If we touch on racial differences, then black women give birth to twins more often. Less common among Asians.

Food

Malnutrition and diets reduce the incidence of twins. However, what exactly should be eaten for the birth of twins is still unknown. For example, in Nigeria - the record holder for the birth of twins - women very often cook dishes from local varieties of yams. It contains a substance that is similar to the female hormone estrogen. Apparently for this reason, the use of yams in food contributes to the release of several eggs.

Season

Scientists have come to the conclusion that twins can be conceived in the spring, during a period of increased hormone activity (my children were born in September, respectively, they settled in my body in the winter). Also, the duration of daylight hours affects multiple conception. This is especially clearly observed during the white nights (this applies to countries where it is common to observe this phenomenon).

Contraceptive

If you abruptly stop taking birth control pills (which you have been taking for 6 months), then pregnancy can occur quite quickly, and the chances of getting pregnant with twins are high.

Hormonal treatment

Infertility is a terrible sentence. If you stimulate ovulation with special drugs prescribed by doctors, pregnancy may occur over time, and sometimes multiple. The body seems to wake up after a long hibernation and can “throw out” a few eggs. However, you can not take drugs without a doctor's prescription. This is very dangerous and can lead to ovarian cysts, bleeding.

ECO

Conception in vitro or also leads to multiple pregnancy. For safety reasons, doctors plant several fertilized eggs in the uterus at once, since the procedure is not cheap, but you still want to get the result. With a good set of circumstances, the embryos take root, and then the gestation process begins. Unfortunately, sometimes IVF ends in nothing.

Here are the main reasons that contribute to the birth of twins. However, if you want to know for sure whether there will be twins in your family, contact geneticists.

ROSSTAT DATA BY DISTRICT

According to various estimates, today in the world there are from 70 to 80 million pairs of twins.

In the early 1980s, there was one twin for every 80-90 births.
In the late 1990s, there was one twin for every 40-45 births.

In the early 1980s, there were one triplets for every 6,400 births.
In the late 90s, there were one triplets for every 800-1300 births.

How often are twins born from representatives of different countries and peoples?

In the US, there are 1 pair of non-identical twins for every 100 people in the population.
and for every 300 people - 1 pair of identical twins.

1/3 of all twins born in the US are identical. In Japan, the proportion of identical twins is 2/3 of all twins.

Hellin's law

According to the pattern derived by American scientists, the frequency of the birth of twins before new methods of treating infertility was as follows:



"Quadruples"
"Fives"	1 in 65,610,000

More than one pair?

If you already have non-identical twins, the chances of getting a second pair are doubled. This is due to the fact that the body of a woman who once conceived dizygotic (non-identical) twins without the use of medications is able to produce several eggs during the period of ovulation.

If you are a twin (if you have twins in previous generations)...

Gender of twins