Decrease text size Default text size Increase text size. Print This Page. Facebook LinkedIn Twitter Email. Detailed Anatomy Ultrasound. Timing Ultrasounds can be done throughout the course of pregnancy.
Who can have this ultrasound? How to prepare for your ultrasound Every ultrasound clinic has different requirements so it is important that you ask the clinic if there are any special instructions before your appointment. What this ultrasound will look at Your baby has now grown enough in size that the sonographer should be able to have a detailed look at your baby, much more so than ultrasounds done in the first trimester of pregnancy.
The sonographer or physician will take measurements and assess all major fetal organs and structures including: Brain Heart Kidneys Bladder Stomach Spine Limbs Sex organs This ultrasound can also provide information about: The fetal position, movement, breathing, and heart rate An estimate of the fetal size and weight The amount of amniotic fluid in the uterus The location of the placenta The number of fetuses Fetal sex — dependent on fetal position Soft markers The detailed anatomy ultrasound will also look for the presence of soft markers which are features that may be associated with an increased risk for fetal chromosome differences.
The ultrasound machine detects sound waves that bounce off of the baby and turns them into an image. These images are used to assess the health and well-being of your baby. A doctor, with expertise in interpreting ultrasound, reviews the images and sends a written report to your prenatal care provider.
Your care provider will then review the findings with you. The endovaginal scan provides a better view of the lower part of your uterus, including the length of your cervix, or to determine the position of your placenta. Your care provider will discuss with you the timing and reasons to use an endovaginal or transabdominal scan in pregnancy. With this information you can decide whether you consent, and if so, what type of ultrasound method you prefer.
Most often, medical ultrasounds are 2 dimensional 2D. This creates a flat image rather than a 3 dimensional 3D image. Medical 2D ultrasound has been used in pregnancy for over 50 years.
Many studies have been done to determine if a medical ultrasound is safe. There have been millions of prenatal ultrasounds over the past few decades with no confirmed health risks for the baby or the mother.
Ultrasound is not an X-ray and does not use ionizing radiation. All ultrasound scans are ordered by a doctor, midwife or nurse practitioner. They must be done by properly trained practitioners who have special knowledge and skill in fetal ultrasound.
When you book your ultrasound, you will receive instructions on how to prepare for your appointment. For example, you may be asked to come to your ultrasound appointment with a full bladder.
Your physician, midwife or nurse practitioner can order an ultrasound at any time during your pregnancy, based on your medical needs.
It may also be used to guide certain procedures that are performed in an attempt to improve the outcome of a fetus with a given problem, e. Operator dependent 2. Small field of view 3. Limited soft tissue contrast 4.
Beam attenuation by adipose tissue 5. Difficult in the presence of low amniotic fluid 6. May be hampered by fetal position 7. Limited cerebral detail, especially later in gestation with ossification of the skull. An example of an Obstetrical Ultrasound checklist for technologists or reporting physicians. There are many superb fetal ultrasound resources developed over many decades by smart and dedicated medical professionals from multiple disciplines; it is not our intention to assemble them all here.
You are encouraged to review the following documents for detailed information on suggested components of thorough ultrasound evaluation of a fetus:. General safety. More intensive research studies were performed specifically on pregnant rats exposed to the maximum power of diagnostic ultrasound for up to 3 days after fertilization also failed to demonstrate any conclusive harmful effects on mitotic chromosomes and DNA damage.
The AIUM position statement indicates that, if exposures are kept as low as reasonably possible, and if performed by a qualified health professional, exposure received from modern diagnostic equipment in the standard clinical setting, ultrasound does not pose a risk.
No teratogenic effects have been documented to date on any study. Although some studies have reported subtle effects of exposure to diagnostic ultrasound during pregnancy, including lower birthweight, delayed speech, dyslexia and left-handedness, other studies could not independently corroborate these conclusions. An extensive longitudinal study performed by John Newnham et al, and published in the Lancet in , followed over children that were subjected to 5 ultrasounds vs just one from 18 weeks to 38 weeks.
The exams consisted of the routine exam and uterine artery Dopplers. The children were followed up to age 8. In their study, they demonstrated no teratogenic effects of ultrasound. Although a slight reduction in birth weight was noted in the multiple-ultrasound group, there was no significant difference in the size of the children between this group and the controls by age 1 year or thereafter.
Thus, there appears to be insufficient evidence to confirm any long-term harmful link from ultrasound when using levels reached in standard clinical practice, and this is reflected in the AIUM position statement:. The first concern in ultrasound is the theoretical risk of tissue damage caused by heat if the temperature of the tissue increases. A prenatal diagnosis can prepare you and your medical team to provide your infant with the best medical care possible throughout your pregnancy and after birth.
Here are the important questions you will want to ask your technician:. The technician will be looking to make sure that the vertebrae are in alignment and that the skin covers the spine at the back. The scan will determine if your baby has two kidneys and if his or her bladder is functioning properly. The technician will look at the positioning of your placenta, specifically looking for placenta previa. The umbilical cord will be checked to determine if it enters the abdomen normally and that it has three vessels.
The technician will also look to see if there is enough amniotic fluid surrounding the baby to allow it to move freely at this stage. This may seem like a lot of scary information, but it is better to be informed and involved in the examination instead of completely unprepared. The anatomy scan really is an exciting examination, where you are able to get a close-up glimpse of your little one moving around.
Enjoy the special moment! So it's almost time for your 20 week ultrasound.
0コメント