Ultrasound, or ultrasound, is a study of internal organs through sound waves. Waves, reflected from internal organs, are recorded using special tools and create images of anatomical details. In this case, ionizing radiation (x-ray) is not used. The normal size of the uterus by ultrasound in adults is an indicator of the health of the genitourinary system in women.
For women, such a study is most often used to examine the uterus and ovaries before, after and during pregnancy, in order to monitor the health of organs, the development of the embryo or fetus. Ultrasound images are captured in real time, so that they can show the movements of internal tissues in organs, such as blood flow in arteries and veins. Ultrasound standards for the size of the uterus are developed and calculated for any condition of a woman.
The uterus, its size
The uterus is located in the pelvis. Although this is usually a median structure, lateral deviation of the uterus is not uncommon. The wide ligaments of the uterus expand from the sides into the pelvic wall. They contain fallopian tubes and blood vessels.
The norms of the size of the uterus by ultrasound are approximately the following. A normal adult uterus has sizes from 7.0 to 9.0 cm (length), from 4.5 to 6.0 cm (width) and from 2.5 to 3.5 cm (depth). The latter indicator is also called anteroposterior size.
During postmenopause, the uterus decreases in size and the endometrium atrophies. Ultrasound and uterus normal sizes have been developed and proven.
Norms of the size of the uterus by ultrasound
When the ovaries undergo involution, a related decrease in estrogen production occurs. This leads to a gradual atrophy and involution of the endometrium. In postmenopausal women, the average thickness of the endometrium is noted as 3.2 +/- 0.5 mm.
Studies usually reveal an inverse relationship between uterine size and time after menopause: uterine size and volume gradually decrease. The greatest changes occur during the first ten years after menopause, and then gradually.
In postmenopausal women, the norms of the size of the uterus according to ultrasound are: 8.0 +/- 1.3 cm in length, 5.0 +/- 0.8 cm in width and 3.2 +/- 0.6 cm in depth (anteroposterior the size).
If there is no menstrual cycle, subsequent changes in the blood supply to the uterus, as a rule, are not determined. If the patient is on hormone replacement therapy, then the size of the uterus, endometrium and cyclic changes may remain. Even the size of the uterus is close to the indicators of the premenopausal state.
In general, estrogen therapy affects the postmenopausal endometrium similarly to estrogen in the normal cycle. Conjugated estrogens have a proliferative effect. Gestagenic therapy can lead to the fact that the endometrium begins to respond in the same way as the normal secretory endometrium.
And when used together with exogenous estrogens, synthetic progestogens reproduce characteristic biochemical and morphological changes in the secretory phase of the normal menstrual cycle.
The blood flow to the uterus also changes while taking hormone replacement therapy. The thickness of the endometrium is almost doubled. For example, before treatment, the average thickness was 0.37 +/- 0.08 cm. After treatment, the values became 0.68 +/- 0.13 cm.
In the study of postmenopausal women, one of the most important uses of ultrasound is the diagnosis and treatment of endometrial cancer. Such studies can determine the normal size of the uterus and ovaries by ultrasound. And in general, intravaginal ultrasound is superior to transabdominal ultrasound for visualization of the myometrium and endometrium.
M-echo. What is it
During the study, not only the size of the uterus is measured. Ultrasound, the M-echo rate is also an important indicator. It reflects the development, condition of the endometrium and its readiness to receive a fertilized egg. It is measured in various phases of the cycle and has certain boundaries.
During menstruation, the endometrium appears as a thin echogenic strip 1-4 mm thick, but ranges from 4 to 8 mm in the proliferative phase. In the secretory phase after ovulation, the endometrial glands are stimulated, and the endometrium appears as a more homogeneous echogenic band with a thickness of 8 to 15 mm.
Rate indicator
We continue to consider such an important indicator as the size of the uterus by ultrasound. What is the M-echo rate?
A shell thickness of 5 mm or less is fairly common in postmenopausal women and reliably eliminates malignancy in women. However, endometrial thicknesses up to 8 mm can be detected in postmenopausal women receiving hormone therapy. It is worth considering further diagnostic studies in postmenopausal women with an endometrial thickness of more than 8 mm in order to exclude endometrial cancer.
Exclude Cancer
Echographic signs of postmenopausal endometrial cancer include:
- a channel filled with liquid;
- thickened uterine cavity;
- enlarged uterus;
- damage to the uterus with a change in the echo picture.
Even an ultrasound scan already accurately shows the presence and extent of myometrial invasion. These studies have shown that the most accurate preoperative diagnosis can allow the right choice of therapy, which may lead to better results.
If the thickness of the endometrium is 8 mm or less in patients with postmenopausal bleeding, then the diagnosis of endometrial cancer can be correctly diagnosed by curettage. Therefore, with a postmenopausal endometrial thickness of 10 mm or more, further examination should be performed using a biopsy or curettage in order to exclude malignancy or hyperplasia.
Some researchers have demonstrated the usefulness of ultrasound dopplerography in the diagnosis of endometrial cancer. The researchers explained the increase in blood flow in the uterine artery as a suspicion of a tumor in patients with malignant diseases: abnormal blood flow can be detected in almost all cases of endometrial carcinoma, as well as
uterine sarcoma. With color Doppler, abnormal findings include irregular, thin, and randomly distributed vessels and abnormal signal flow rates.
Why measure the cervix
Every pregnant woman is at risk of premature birth, but most think it will never happen to them. When they encounter this, they recall prevention and additional research. The most accessible and harmless study is an ultrasound, in which the doctor can make a diagnosis of threatening premature birth.
Numerous studies have shown that an ultrasound scan of the cervix from approximately 20 to 24 weeks of gestation is a strong indicator of preterm birth. The length of the cervix can most accurately be measured using transvaginal ultrasound. If the woman is not pregnant, then the size of the cervix by ultrasound (normal) is about 4 cm.
What is cervical shortening?
It has been proven that within 24 weeks of gestation the average size of the cervix is 3.5 cm. If this figure is less than 2.2 cm, women face a 20 percent chance of preterm delivery. And with a length of 1.5 cm or less, the risk of spontaneous preterm birth is almost 50 percent. Length is expected to decrease as pregnancy progresses.
Sizes of the cervix by ultrasound (normal):
- at 16-20 weeks - 4.0-4.5 cm;
- at 24-28 weeks is equal to 3.5-4.0 cm
- at 32-36 weeks - 3.0-3.5 cm.
Most doctors will prescribe a woman transabdominal ultrasound for a period of about 20 weeks. If the length is less than 4 cm, transvaginal ultrasound is done to get a more accurate measurement.
A shortened cervix between 20 and 24 weeks is a dangerous symptom.
With the help of transvaginal ultrasound, you can see both the top and bottom of the cervix. In this case, it looks like a funnel. The widest part of the funnel is closest to the body of the uterus, and the narrowest part is located towards the vagina. When the cervix is shortened even more, it will look like a “V” on an ultrasound scan.
Normally, the cervix has the shape of a tube. More than 50 percent of pregnant women with the pathology of this organ have a premature birth.
Size of the uterus by ultrasound
The norm during pregnancy depends on the gestational age. The program for calculating the gestational age is incorporated in sonographs according to measurements of the size of individual organs of the fetus and uterus.
If you apply a comparison with fruits, then the size of the uterus by ultrasound (normal in mm) will be as follows.
1. Before pregnancy, the uterus is about the size of an orange and is not detected.
2. At about 12 weeks of gestation, the uterus becomes the size of a grapefruit. If the twins are born, the uterus will begin to grow faster.
3. At 13-26 weeks, the uterus grows to the size of a papaya. The bottom of the uterus is located over time from the womb to the navel.
4. Starting from 18-20 weeks, the doctor will measure the distance from the
pubic bone to the bottom of the uterus. This is the height of the uterine fundus. Size usually corresponds to week of pregnancy.
If the size of the uterus coincides with the gestational age, then this is a sign that everything is going well. If the indicator is too large or too small, this may mean some complication of pregnancy. Additional testing may be required. The doctor needs to know the size of the uterus by ultrasound. The norm during pregnancy of this indicator means that everything goes as it should.
5. During the third trimester, the uterus finishes growing and becomes the size of a watermelon. When the time for childbirth comes, the uterus is at the level of the lower chest, and before childbirth it should go down into the pelvis.
Postpartum period
What are the sizes of the uterus after childbirth? The norm for ultrasound corresponds to the duration of pregnancy. About a day or two after birth, the uterus will be approximately 18 weeks old and decrease over the next days. If healing goes according to plan, then in a week the uterus will be the size of a 12-week gestation period, and by the sixth week it should return to its normal size.
Ovaries
The ovaries are usually located on both sides of the uterus, although during the examination, determining them in places above or behind the uterus is not uncommon. The ovary is most often located in front of the bifurcation of blood vessels on the anterior and posterior branches. Successful visualization of the ovaries requires good access.
During postmenopause, the ovaries undergo changes, characterized by a decrease in size and the absence of folliculogenesis. In fact, reliable identification of the ovary in many cases cannot be done by demonstrating an ovarian cyst when the follicle is surrounded by a parenchyma. Sometimes you have to resort to scanning along the route of the internal iliac vessels to find its location.
Usually, an inverse relationship is found between the size of the ovaries and the time elapsed since menopause: the size of the ovaries progressively decreases over time. However, in patients receiving hormone therapy, one can see the absence of changes in ovarian volume.
Resizing
Normally, after menopause in women, the size of the ovaries is 1.3 +/- 0.5 cm 3 . There is no menstrual cycle in menopause, so changes in the blood supply to the ovary are usually not visible when examined in the normal postmenopausal period.
These cyclical changes, however, may be apparent if the patient is on hormone replacement therapy. In fact, the blood flow pattern of the premenopausal ovary in postmenopausal women should aim the doctor to search for a history of hormone replacement therapy or cancer changes. Ultrasound and Doppler can be of great help in the differentiation of benign and malignant processes.
Performing dopplerography of the uterus for appendages should be performed:
- between 3-10 days of the menstrual cycle;
- between 3-10 days in postmenopausal women, if the woman is on hormone replacement therapy;
- at any time in postmenopausal women without treatment.
Thus, it is not only during pregnancy that it is important to know the size of the uterus by ultrasound. The norm of this indicator, as well as the size of the ovaries, is an important sign of a woman's health in any period.
Use of the method in non-pregnant women
There are many reasons for performing an ultrasound scan, including:
- pathology of the structure of the pelvis;
- unexplained vaginal bleeding;
- pelvic pain;
- suspected ectopic pregnancy;
- infertility;
- checking for cysts or uterine fibroids;
- checking the correct placement of the IUD.
The norms of the size of the uterus by ultrasound depend on how old the woman is, how many pregnancies and childbirth she has, how the menstrual function proceeds, etc. Now consider the difference in indicators by age.
Sizes of the adult uterus
What are the normal sizes of the uterus by ultrasound in adults? About 7 centimeters long and 4 centimeters wide and thick, plus or minus a couple of centimeters. This is the data of many years of research.
These indicators are the norm of the size of the uterus by ultrasound in adults. As a rule, an increase in size is noted if the woman had a birth. Myoma can make these measurements very large, however, like adenomyosis.
The ovaries are usually in size from 2 to 3 centimeters. Of course, volumes increase if there is a large follicle or cyst.
Sizes before puberty
What are the sizes of the uterus in this case by ultrasound? The norm in the prepubertal period (before puberty) is about 3.5 cm in length, and the average thickness is 1 cm. Hormonal stimulation that occurs during puberty leads to rapid growth and changes in the size of the uterus.
Dimensions after puberty
The normal length in this period is about 7.6 cm, the width is 4.5 cm. The average normal thickness is 3.0 cm.
Thus, the normal size of the uterus by ultrasound in adolescents with a normal menstrual cycle is only slightly different from the size of the uterus of an adult woman.
After menopause, the uterus, as a rule, decreases in size, and the ovaries can eventually turn out to be nothing more than tissue debris. This is because the normal size of the uterus and ovaries by ultrasound during menopause is significantly reduced.
Conclusion
So what are the average rates?
It is generally accepted that the size of the uterus by ultrasound (normal in mm) in women:
- length - about 70;
- width - closer to 55;
- front-back size - 40 mm.
Larger sizes are not always considered pathological. But in this case, it is necessary to conduct a study to exclude fibromyoma, adenomyosis, malformations, pregnancy.