Ultrasound, or echography, is a study of internal organs using sound waves. Waves reflected from the internal organs are recorded using special instruments and create images of anatomical details. In this case, ionizing radiation (X-ray) is not used. The normal size of the uterus on ultrasound in adults is an indicator of the he alth of the genitourinary system in women.
For women, this study is most commonly used to examine the uterus and ovaries before, after and during pregnancy to monitor organ he alth, embryonic or fetal development. Ultrasound images are captured in real time so that they can show the movements of internal tissues in organs, such as the flow of blood in arteries and veins. The norms for the size of the uterus according to ultrasound are developed and calculated for any condition of a woman.
Uterus,her measurements
The uterus is located in the small pelvis. Although it is usually a midline structure, lateral deviation of the uterus is not uncommon. The broad ligaments of the uterus expand from the sides into the pelvic wall. They contain the fallopian tubes and blood vessels.
The norms for the size of the uterus according to ultrasound are approximately as follows. A normal adult uterus measures 7.0 to 9.0 cm (length), 4.5 to 6.0 cm (width), and 2.5 to 3.5 cm (depth). The last indicator is also called the front-back size.
During the postmenopausal period, the uterus shrinks and the endometrium atrophies. The normal sizes of the uterus and ovaries by ultrasound have been developed and proven.
Norms for the size of the uterus by ultrasound
When the ovaries undergo involution, there is an associated decrease in estrogen production. This leads to gradual atrophy and involution of the endometrium. In postmenopause, the average thickness of the endometrium is noted as 3.2 +/- 0.5 mm.
Research generally reveals 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 normal size of the uterus according to ultrasound: 8.0 +/- 1.3 cm in length, 5.0 +/- 0.8 cm wide and 3.2 +/- 0.6 cm deep (anterior-posterior dimension). If there is no menstrual cycle, subsequent changes in the blood supply to the uterus are usually not detected. 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 approachingpremenopausal state.
In general, estrogen therapy affects the postmenopausal endometrium in a manner similar to estrogen in the normal cycle. Conjugated estrogens have a proliferative effect. Progestogen therapy may cause the endometrium to respond in a manner similar to the normal secretory endometrium.
And when used together with exogenous estrogens, synthetic progestogens reproduce the 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 almost doubles. 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 applications of ultrasound is the diagnosis and treatment of endometrial cancer. Such studies allow you to determine the normal size of the uterus and ovaries by ultrasound. And in general, intravaginal ultrasound surpasses the capabilities of transabdominal for visualization of the myometrium and endometrium.
M-echo. What is this
When conducting a study, not only the size of the uterus is measured. According to ultrasound, the M-echo norm 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 different phases of the cycle and has certain boundaries. During menstruation, the endometrium appears as a thin echogenic strip of 1-4 mmthick, but varies 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 uniform echogenic band 8 to 15 mm thick.
Normal indicator
We continue to consider such an important indicator as the size of the uterus by ultrasound. What is the M-echo rate?
Intima thickness of 5mm or less is fairly common in postmenopausal women and reliably rules out malignancy in women. However, endometrial thickness up to 8 mm can be found in postmenopausal women receiving hormone therapy. Consideration should be given to further diagnostic testing in postmenopausal women with an endometrial thickness greater than 8 mm to rule out endometrial cancer.
Ruling Cancer
Sound signs of postmenopausal endometrial cancer include:
- liquid-filled channel;
- thickened uterine cavity;
- enlarged uterus;
- damage to the uterus with a change in the echo pattern.
Even ultrasound already accurately shows the presence and degree of invasion of the myometrium. These studies have shown that the most accurate preoperative diagnosis can allow the right choice of therapy, possibly leading to improved outcomes.
If the thickness of the endometrium is 8 mm or less in patients with postmenopausal bleeding, then the correct diagnosis of endometrial cancer can be made by scraping. Therefore, with a postmenopausal endometrial thickness of 10 mm or more, further examination should be carried out using a biopsy or curettage,to rule out malignancy or hyperplasia.
Some researchers have demonstrated the usefulness of Doppler ultrasound in the diagnosis of endometrial cancer. The researchers attributed the increase in blood flow in the uterine artery to the 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 the presence of irregular, thin, and chaotically distributed vessels and abnormal signal flow rates.
Why measure the cervix
Every pregnant woman is at risk of preterm labor, but most think it will never happen to them. When faced with this, they are reminded of prevention and additional research. The most accessible and harmless study is ultrasound, in which the doctor can diagnose threatened preterm labor.
Multiple studies have shown that an ultrasound scan of the cervix from approximately 20 to 24 weeks of pregnancy is a strong indicator of preterm labor. The length of the cervix can most accurately be measured using transvaginal ultrasound. If a woman is not pregnant, then the size of the cervix according to ultrasound (normal) is about 4 cm.
What is a short cervix?
At 24 weeks of gestation, the average cervical size has been proven to be 3.5 cm. If this figure is less than 2.2 cm, women experience a 20 percent chancepremature birth. And with a length of 1.5 cm or less, the risk of spontaneous preterm birth is almost 50 percent. The length is expected to decrease as the pregnancy progresses.
Cervix size by ultrasound (normal):
- at 16-20 weeks - 4.0-4.5 cm;
- at 24-28 weeks is 3.5-4.0cm
- at 32-36 weeks - 3.0-3.5 cm.
Most doctors will give a woman a transabdominal ultrasound around 20 weeks. If the length is less than 4 cm, a transvaginal ultrasound is done to get a more accurate measurement.
A shortened cervix between 20 and 24 weeks is a dangerous symptom. With a transvaginal ultrasound, you can see both from above and below 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 shortens further, it will look like a “V” on the ultrasound.
Normal, the cervix is shaped like a tube. More than 50 percent of pregnant women with pathology of this organ experience premature birth.
Uterine size by ultrasound
The norm during pregnancy depends on the gestational age. The program for calculating the duration of pregnancy is incorporated in sonographs according to the measurements of the sizes of individual organs of the fetus and uterus. If we apply a comparison with fruits, then the size of the uterus according to ultrasound (normal in mm) will be as follows.
1. Before pregnancy, the uterus is about the size of an orange and is undetectable.2. At about 12 weeks pregnant, the uterus becomes the size of a grapefruit. If atwins 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 at 18-20 weeks, the doctor will measure the distance from the pubic bone to the fundus of the uterus. This is the height of the fundus of the uterus. The size usually corresponds to the week of pregnancy.
If the size of the uterus matches 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 kind of 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 comes for childbirth, the uterus is at the level of the lower part of the chest, and before childbirth it should fall lower into the pelvis.
Postpartum
What is the size of the uterus after childbirth? The norm for ultrasound corresponds to the duration of pregnancy. About a day or two after giving birth, the uterus will be about 18 weeks in size and shrink over the following days. If healing goes according to plan, then in a week the uterus will be the size of a 12-week gestation, and by the sixth week it should return to its normal size.
Ovaries
The ovaries are usually located on either side of the uterus, although it is not uncommon to find them above or behind the uterus on examination. Ovarymost often located in front of the bifurcation of the vessels on the anterior and posterior branches. Good access is essential for successful visualization of the ovaries.
During postmenopause, the ovaries undergo changes characterized by a decrease in size and the absence of folliculogenesis. As such, reliable identification of the ovary in many cases cannot be made by demonstrating an ovarian cyst when the follicle is surrounded by parenchyma. Sometimes you have to resort to scanning along the route of the internal iliac vessels to find its location.
There is usually an inverse relationship between ovarian size and time since menopause: ovarian size progressively decreases over time. However, no change in ovarian volume can be seen in patients receiving hormone therapy.
Sizing changes
Normal after menopause in women, the size of the ovaries is 1.3 +/- 0.5 cm3. There is no menstrual cycle at menopause, so changes in the blood supply to the ovary are usually not visible on examination in a normal post-menopausal period.
These cyclic changes, however, may be evident if the patient is on hormone replacement therapy. In fact, the blood flow pattern of a postmenopausal premenopausal ovary should direct the clinician to look for a history of hormone replacement therapy or cancerous changes. Ultrasound and Doppler can be of great help in differentiating between benign and malignant processes.
Doppler ultrasound of the uterus for the appendages must be done:
- between 3-10 days of the menstrual cycle;
- between 3-10 days postmenopausal if the woman is on hormone replacement therapy;
- anytime postmenopausal without treatment.
Thus, not only during pregnancy 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 he alth in any period.
Using the method in non-pregnant women
There are many reasons for having an ultrasound, including:
- pathology of the pelvic structure;
- unexplained vaginal bleeding;
- pelvic pain;
- suspected ectopic pregnancy;
- infertility;
- checking for cysts or uterine fibroids;
- Checking correct IUD placement.
The norms for the size of the uterus according to ultrasound depend on how old the woman is, how many pregnancies and childbirth she had, how the menstrual function proceeds, etc. Now consider the difference in indicators by age.
Adult uterus size
What is the normal size of the uterus on ultrasound in adults? About 7 centimeters long and 4 centimeters wide and thick, give or take a couple of centimeters. These are the data of many years of research.
These figures are the norm for the size of the uterus according to ultrasound in adults. As a rule, there is an increase in size if the woman had childbirth. Myoma can do thesemeasurements are very large, however, as is adenomyosis.
The ovaries are usually 2 to 3 centimeters in size. Of course, volumes increase if there is a large follicle or cyst.
Sizes before puberty
What is the size of the uterus on ultrasound in this case? 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.
Sizes after puberty
Normal length in this period is about 7.6cm, width is 4.5cm. Average normal thickness is 3.0cm.
Thus, the normal size of the uterus on 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 tends to shrink in size, and the ovaries may end up being nothing more than remnants of tissue. This is so, since the normal size of the uterus and ovaries on ultrasound during menopause is significantly reduced.
Conclusion
So what are the averages?
It is generally accepted that the size of the uterus according to ultrasound (normal in mm) in women:
- length - about 70;
- width - closer to 55;
- front-back size - 40 mm.
Large size is not always considered a pathology. But in this case, it is necessary to conduct a study to exclude fibromyoma, adenomyosis, malformations, pregnancy.
