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How identical twins look on ultrasound. Pregnancy with twins on ultrasound: distinctive features. Excessive morning sickness

Hello dear subscribers! Want news? You will have twins! Guess by what signs I understood this? This discovery usually awaits a woman during a visit to a gynecologist. But you can find out earlier. When is the best time to get an ultrasound scan for twins in the early stages? Mom-to-be, rather check your symptoms and plan your trip to the doctor.

Symptoms of carrying twins

Ultrasound is the most reliable method for detecting multiple pregnancies. But besides it, there are symptoms that make it possible to suspect pregnancy with twins. They can manifest themselves in several signs at once, or they can accompany the development of a dizygote one at a time. What are these clinical manifestations?

  • It is unusually greasy on the test. As a rule, in the early stages, it is barely noticeable. Its thickness indicates the presence of a large amount of hCG (human chorionic gonadotropin), which is used to diagnose pregnancy. If it is more than the norm, this may indicate multiple pregnancy, and it is visualized as a bold stripe. Of course, a blood test for this hormone will give the most accurate result.


  • Who else but you know what's going on. Premonition rarely fails women, they are endowed with it by Nature.

The best way to learn about multiple pregnancies

And yet, only ultrasound can give you accurate knowledge. Ultrasound is able to look inside the uterus, breaking through all the tissues. He will tell about what he saw by displaying the image on the display screen. The procedure is safe for the mother and the unborn child. It is not in vain that in each trimester a special ultrasound screening is carried out so as not to miss congenital anomalies of development, the uncomfortable state of the baby, and his intrauterine death.

Ultrasound is able, reflecting from different sides of the zygote, and then the fetus, to create a three-dimensional image. It separately shows white bone tissue, black amnion (amniotic fluid), and the rest of the tissue stained in gray tones. This is possible due to echogenicity - different densities of the examined tissues. even the earliest pregnancy is visible on ultrasound as a small black dot or circle. But already at a period of 6 weeks, the embryo itself, the yolk sac and the heartbeat in the form of a specific flicker are clearly defined.

What are twins?

By the way, in addition to dividing twins into identical and bizygotic, there is another gradation of them into three types:


It only occurs in identical twins with one placenta. It is also called fetal fetal transfusion syndrome (FFT). The bottom line is the development of one fetus to the detriment of another with impaired blood circulation, the occurrence of hypoxia. The prognosis for the donor fetus is unfavorable.

When can I go for an ultrasound scan for twins?

Ultrasound "sees" twins very early. Starting from the 5th week of pregnancy in the first trimester (my option). But many doctors choose to wait up to 12 weeks for a final diagnosis. If during this time one of the twins is not absorbed by the placenta due to non-viability, then we can safely diagnose twins. And it’s better not to bother mom until that time. After all, this is pure physiology, which does not harm either her or her baby.

By the way, identical twins, developing normally, can also be distinguished at this time (12 weeks). In general, twins are rendered reluctantly. Old equipment may not notice them at all. Therefore, do 3D or 4D ultrasound in medical centers equipped with new modern devices.

I look forward to your comments and see you soon!

Sowed in you hope for twins, then I want to know about such happiness as soon as possible.

Surely only a doctor will say this after an ultrasound examination, and then not the first, but already in the second trimester of pregnancy.

Therefore, while you can only guess about double happiness or rely on several signs that will help confirm the fact of pregnancy with two children.

Doubly increased fatigue

Any pregnant woman feels tired literally from the first day, but many women who are pregnant with twins get tired even more than women who carry one baby. Normal for lethargy, fatigue, drowsiness doubles in the literal sense of the word, because the mother's body works with greater strength to endure two toddlers.

It is easier for a mom who is not expecting her first child to determine that she is gets tired more , but primiparous (as doctors like to call us) her condition is not very clear.

If you notice that a pregnant girlfriend, although she is tired, is still fluttering like a butterfly, but for you walk to work - a real feat, then the probability of twins is very high. Although it is necessary to take into account the accompanying factors, due to which lethargy may appear: stress, workload, or.

Excessive morning sickness

Multiple pregnancies increase not only fatigue or drowsiness, but also morning sickness. But this will not necessarily be nausea or vomiting with a vengeance, it may simply be a breakdown, which will pass towards the middle of the day.

remember, that each organism is individual ... For some future moms it was getting stronger, for others it was not at all and they felt great. Therefore, well-being is not yet an indicator that you will have only one baby.

Mom Julia S tells her story: “When I carried my two boys, I felt great. There was no toxicosis throughout the pregnancy. True, I was terribly tired, I wanted to sleep all the time, but that passed later, when I gave birth and the boys grew up :) But seriously, my pregnancy with two children was almost no different from the pregnancy of my sister, who gave birth to one girl. True, my belly has grown very large, so I couldn't do without it. "

Heredity + intuition

If twins have already been born in a family history, the likelihood of becoming a mother of two children increases. Plus - your intuition. The notorious female intuition, especially the expectant mother, is unlikely to let you down. If you have any suspicions, share them with your doctor.

Frequent or early movement of the baby

The woman feels the first movements of the baby on average at 18 (in anticipation of the second child - at the 16th week). If you feel early movements, then this may mean that there are two babies in the womb.

Elena Bezuglova, gynecologist: “In the early stages, a woman who carries two or more children will have a clear discrepancy between the size of the uterus and the timing of the delay in menstruation. At a later date, the doctor will identify several large parts of the fetus and 2 or more heartbeats. A mother can feel a multiple pregnancy by a large number of movements. By the way, the movements of a child during multiple pregnancies are no different from those that occur during pregnancy with one baby. ".

Elevated hCG levels

It was the level of human chorionic gonadotropin (hCG) that prompted you in a pregnancy test about a new position. And since then, after 10 days from the moment of conception, doctors control the level of the hormone in the body. Sometimes, pregnancy with twins can lead to an extreme increase in hCG levels.

Weight gain

As a rule, expecting twins, the expectant mother gains 4-5 kilograms more than her friend, who is pregnant with one child. But remember that weight gain may be associated primarily with diet ... It also depends on the constitution of the woman's body, her height and "pre-pregnant" weight. Therefore, it is better not to overeat, and generally eat right, because the health of the unborn child depends on it.

High results of gestational age

During a visit to your doctor, be sure to measure the distance from the upper part of the uterus to the upper part of the pubis in order to find out the gestational age of the baby. The result above the norm may appear due to pregnancy with twins, because two babies expand the uterus more than one (everything is logical, isn't it?). But again: there may be other factors that influence the results.

Abnormal results in AFP tests

A blood test for the level of alpha-fetoproteins (AFP) is waiting for you. It is done in order to determine the risk of birth defects in the baby. If you are expecting twins, it is possible unusually tall or a positive result. In the latter case, the doctor will definitely do an ultrasound scan to make sure.

Waiting for a baby is a happy period for parents. Many are waiting for the first ultrasound scan with trepidation, because it can confirm pregnancy, suggest gender and find out if there are twins for an ultrasound scan or one baby.

At the first visit to the gynecologist, you may find that the uterus is enlarged, its size does not correspond to the date. This may indicate multiple pregnancies, but only an ultrasound scan will help confirm twins.

Ultrasound of twins or twins follows a specific protocol. Each ultrasound is designed to carefully assess the condition of the fetus, the functioning of the placenta, blood circulation, presentation.

How long can twins be determined?

If they are identical twins, then the separation of the egg occurs from the 1st to the 13th day after fertilization. Fraternal twins are produced when two different eggs are fertilized. How many embryos in the uterus can be determined in the early stages, at 4 and the ovum is already visible (defined as a dark, rounded formation in the uterus).

As a rule, a woman learns about the number of children at 12 weeks. During this period, their length reaches 60 mm, and the weight of each is about 8 g. At the first ultrasound, the risks are determined, a detailed research protocol is drawn up.

You can see twins on an ultrasound scan in the following video:

Types of multiple pregnancies

With multiple pregnancies, it is assumed that doctors pay more attention to women. The tactics depend on the type of multiple pregnancy, or rather on the chorionicity (the number of placentas).

Types of twins:

  1. diamniotic dichorial - each has its own placenta and its own fetal bladder. In 70% of cases, they are not identical.
  2. diamniotic monochorial - one placenta for two, each has its own bladder. It occurs in 65% of pregnancy with identical twins. On ultrasound at 4-5 weeks, it looks like a single placental mass without an interfetal septum.
  3. monoamniotic, monochorionic - common placenta, common bladder in two fetuses. Rare.
  • With diamniotic dichorionic twins, each twin has its own source of nutrition. With this form, the risks of malformations and death are minimal.

  • With diamniotic monochorionic twins, sometimes one of the children develops better than the other - close supervision is required. In severe cases, laser coagulation (cauterization) of the vessels is performed, which contributes to the discharge of blood to a larger child.

  • With monoamniotic monochorionic - the presence of conjoined twins should be excluded. It is this view that indicates a late separation, so there is a risk of anomaly.

Diagnostic errors

The procedure may not show twins when using an outdated apparatus. Doctors with insufficient qualifications may not see twins, but this is rather an exception. If the first examination takes place in the 2nd or 3rd trimester, ultrasound may not show all children with multiple pregnancies (3 or more).

There are cases when a study at 4-5 weeks showed two fetal eggs, and subsequent studies only one. This may be due to the death of the embryo or the development of an empty fetal egg (anembryonia).

Labor usually begins in or - due to overstretching of the uterus, labor begins earlier. Before childbirth, an ultrasound scan is shown to determine the management tactics. Often, the expectant mother is hospitalized in the maternity hospital a few days before the expected birth. If necessary, a planned caesarean section is performed.

How did you know about twins? Tell us about your experience in the comments, share an article. All the best.

In accordance with the pregnancy management program, a woman undergoes screening, including ultrasound and laboratory blood tests, once in each trimester. Complicated or multi-embryonic pregnancies are controlled more often. Twins on an ultrasound scan are determined with almost one hundred percent guarantee. They can make mistakes only under the influence of unfavorable factors, which include:

  • faulty or outdated diagnostic device;
  • insufficient qualifications of medical specialists;
  • unnatural arrangement of embryos, when one fetus "hides" behind another.

The latter factor takes place only in the early stages. Even if twins were not seen at the first ultrasound, subsequent screening will certainly show the presence of two embryos.

Causes of a twin pregnancy

Twin pregnancy has a genetic (hereditary) basis. On the female line, this feature is transmitted more often. Other reasons may be: in vitro (unnatural) fertilization, abnormal development of the structure of the uterus. In addition, the likelihood of getting pregnant with two babies immediately increases with age. In women aged 35+, this phenomenon occurs several times more often.

Definition of twins without ultrasound

A woman can notice the primary signs of multiple pregnancy on her own:

  • pathological toxicosis in the first trimester;
  • accelerated weight gain and an increase in abdominal volume.

In the second half of the perinatal period, the doctor determines twins according to the following criteria:

  • abnormally elevated levels of the hormone human chorionic gonadotropin (hCG) and ACE protein;
  • a reduced level of iron in the blood;
  • the size of the uterus, enlarged inappropriately;
  • clear palpitations of two hearts during auscultation (listening with a stethoscope);
  • early double movement of fetuses in the uterus (children begin to push earlier, because they become cramped).

An accurate determination of twins in the early stages is possible only through ultrasound.

Determination of the timing and types of multiple pregnancies

Women who have a hereditary predisposition to having two children at once are always worried about how long twins can be determined. Despite the fact that in obstetric and gynecological practice there are certain periods, much depends on the type of pregnancy, therefore it is an individual indicator.

The location of the twins can have several variations.

The presence of twins on an ultrasound scan is established by listening (characteristic gurgling) of the beating of two hearts, two hollow membranes (amniotic sacs) with amniotic fluid and two provisional organs (placentas). The types of possible development of babies in the womb are determined according to the placenta-forming organ - the chorion and the amniotic fluid - the amnion.

There are three options for a twin pregnancy:

  • Dichorial diamniotic... The localization of each embryo is determined by a personal "baby place" (placenta) and amniotic bladder. With this development, babies are usually heterogeneous. Twins can be seen already during the first screening, starting from 5-6 weeks of gestation.
  • Monochoryl diamniotic... Embryos are located in different amniotic membranes, united by one "baby seat". These twins can be seen around 9-11 weeks of age.
  • Monochorionic monoamniotic... As a rule, such identical twins are visible on ultrasound only at the second screening. Future children are connected by a common amniotic bladder and a common placenta. This is the most problematic type of two-embryonic pregnancy and is difficult to tolerate without complications.

The nature of complications

Bearing two fetuses is accompanied by a double load on the body of the expectant mother. The main types of possible complications are: recurrence of chronic diseases (if any), severe toxic damage (toxicosis), anemia (low levels of hemoglobin in the blood), abnormal development of embryos, placental insufficiency (changes in the interaction of the mother and children).

For these and other reasons, ultrasound diagnostics for women who are pregnant with two children are prescribed more often than once per trimester and are mandatory before delivery. It will be useful for future mothers to know about the existence of such a situation as an interruption in the development of one of the babies. At the initial examination, two children were noticed, and the repeated ultrasound showed the presence of only one embryo.

This situation is not abnormal when the fetus does not freeze, but dissolves in the placenta. You should not be afraid of this.

Ultrasound imaging

The objective period in which week two fetuses are visualized is the fifth week from the moment of conception. On the monitor screen, ultrasound shows two dark spots in the uterine cavity. As the babies form, the picture will change. When there are two children, they tend to lag slightly behind in phenometry (sizing by ultrasound).

  • At the eleventh week, babies are 43–48 mm in size.
  • A week later, children grow up to 60 mm, weighing about 8 g.
  • In the middle of pregnancy (20 weeks), the weight of each fetus is close to 350 g, while the weight does not have to be the same. One child may well be larger than the other. Babies no longer look like dark formations. They have good visualization of the limbs, other parts of the body and internal organs.
  • By the time of the third screening, children are gaining body weight up to 2 kg.

After the procedure, the ultrasound doctor can print a snapshot of the image, and the parents, if they wish, will receive the first photo of their babies. Delivery of twins is often premature. Natural childbirth is not always possible due to the size of the children, the weak labor of the mother, the peculiarities of the presentation of the fetus. To avoid complications, doctors prefer to resort to a caesarean section.


Two-fetal pregnancy at 15 weeks. Photo from the ultrasound image

Twins or twins

The definition of "twins" is not typical of medicine. Twins can be heterogeneous (dizygotic), when a woman matures not one, but two eggs and their fertilization is carried out by different spermatozoa. These children are called twins. Different-egg babies can be heterosexual, completely different from each other, have a different blood group and rhesus. These are different children, which may not have the same biological clock, tastes and habits.

In the case of dividing an already fertilized egg in half, identical (monozygous) embryos or twins are obtained, born from one egg. Such children are always same-sex, and pregnancy, most often, will be monochorionic diamniotic. Twins have the same appearance, similar characters and habits, and often suffer from the same diseases. Often, such children (later adults) have the ability to feel each other's experiences and pain.

Girls and boys

When carrying one child, it is possible to establish its gender by ultrasound at the second screening. The optimal period is the twenty-second week. When it comes to twins or twins, gender differentiation can be difficult. The fact is that children often have an incorrect presentation.

Gender will not be visible if both babies turned away or "hide" behind each other, hiding the genitals during the examination. Today there is no more informative diagnostic method than ultrasound in the perinatal period. It is possible to see twins on an ultrasound scan with almost a 100% guarantee.

A pregnant woman undergoes a routine ultrasound scan three times, once in each trimester. With the development of several embryos in the uterine cavity, the procedure is performed monthly. The following factors are predisposed to conceiving two children: heredity in the mother's line, in vitro (artificial) fertilization, abnormal uterine structure.

Women with such indications are usually concerned with three main questions:

  • What week does ultrasound diagnose twins?
  • Can you not see twins on an ultrasound scan?
  • What gender are the children, and when can it be determined?

There are objective periods of ultrasound scan for establishing a multi-embryonic pregnancy, but much depends on the type of multiple pregnancy. Therefore, the time range for determining the number of embryos, and possible errors during the examination, are individual indicators.

Types of multiple pregnancies and the timing of the determination on ultrasound

Twin pregnancy is determined by listening to two heart rhythms, the presence of two hollow membranes with amniotic fluid (fetal bladder), and two embryonic organs (placenta or "baby seat"). Chorion - the source of the development of the placenta and the amnion - the amniotic fluid, give the name to the types of development of twins in the womb.

Dichorial diamniotic twins

Each embryo is located in a personal amniotic fluid and has its own "baby seat". With this type of development, twins, most often, are fraternal, and it is possible to determine twins on ultrasound diagnostics already in the fifth week of bearing children, that is, at the first screening performed by a woman.

Monochoryl diamniotic twins

With this type of pregnancy, the presence of two children can be noticed no earlier than 9-11 weeks, since the children are in different amniotic bladders, which are located in the same "child's place".

Schematic example of twins of the first (monochorionic diamniotic) and second (dichorionic diamniotic) type

Monochorionic monoamniotic twins

Ultrasound, as a rule, cannot show such identical twins at the first screening performed by a woman. The embryos are connected by a common amniotic membrane and are located in the same placenta. Children of this type are difficult to carry, often with complications.

Can any two embryos in the uterine cavity be called twins? No. Twins are only identical twins, which are formed by dividing one fertilized egg by two. This option is most often inherent in monochorionic diamniotic twins. Babies born from the same egg will always be same sex. Fraternal babies can be a boy or a girl.

Could there be a pregnancy in which early screening showed the presence of two babies, and there is no second embryo on subsequent ultrasound examinations? This happens when the development of one of the embryos is interrupted. At the same time, he does not freeze, but completely dissolves in the placenta.

Ultrasound error

It is possible to make a mistake when making a diagnosis of twins, perhaps only under unfavorable examination conditions. These include:

  • ignoring the first ultrasound examination by the woman herself;
  • outdated low-quality equipment used for examining a pregnant woman;
  • lack of the necessary qualifications among medical professionals who did not notice the presence of a second fetus;
  • incorrect arrangement of embryos in the womb, when one baby, as it were, obstructs the other.

The latter option is quite rare, and if one of the children was not seen at the first screening, it will certainly be seen on subsequent ultrasound examinations.

If an ultrasound scan did not show the presence of twins or an error occurred, after half of the pregnancy, the gynecologist will detect the presence of two babies and without ultrasound.

For this, there are the following signs:

  • high (twice or more) level of the hormone human chorionic gonadotropin (hCG);
  • clear listening to the rhythmic beating of two hearts with a stethoscope;
  • determination by touch (two heads, two pelvis);
  • double movement in the uterus;
  • significantly increased volume of the uterus.


It is better to entrust ultrasound examination to a trusted highly qualified specialist

Boys or girls?

As a result of an ultrasound study in a single pregnancy, the sex of the baby can be established in the second trimester. The ideal period for this procedure is the 20th to 22nd week. In twin pregnancies, the timing remains the same, but a couple of children often hide behind each other, and medical specialists do not see the genitals.

Therefore, it can be quite difficult to differentiate children in the womb by gender. To date, the method of ultrasound diagnostics during pregnancy is the most highly informative. It is possible to recognize twins by ultrasound in 98% of cases.