Once you find out that you are pregnant, you should receive your first ultrasound within 1-15 weeks. During the ultrasound, the technician and doctor will be able to tell if this is a healthy pregnancy or not. During the first trimester of pregnancy, an ultrasound will not show the limbs or organs in detail, but it will be able to help estimate the gestational age of the fetus, along with the number of fetuses in the body. The ultrasound will also be able to show whether the fetus has a viable heart rate. Last, a first trimester ultrasound can check for any abnormalities such as an ectopic pregnancy.
Most anatomy ultrasounds are performed during the second trimester of the pregnancy, sometime between 18 and 22 weeks of pregnancy. This ultrasound focuses on the fetal anatomy to assure that the fetus is growing and developing as it should be. During the ultrasound, the fetus(s) will be measured from crown to rump, around the middle, around the head and the fetus’s weight will be obtained. The four chambers of the heart, the kidneys, bladder, stomach, brain, spine and sex organs will also be looked at. Lastly, the amniotic fluid levels, location of placenta and fetal heart rate are also looked at. This anatomy ultrasound will also be able to inform you of the sex of the baby. The ultrasound technician will inform you if there are any obvious abnormalities of the fetus following the anatomy ultrasound.
A saline infusion sonohysterography (SIS) is an ultrasound that uses a small amount of saline solution, or salt solution, that is inserted into the uterus. This technique allows for the lining of the uterus or endometrium to be clearly seen on the ultrasound scan. An SIS may be ordered to diagnose endometrial thickening, or a small growth such as a polyp in the endometrium of the uterus. An SIS is also ordered to assess for patients who are experiencing post-menopausal bleeding.
A transvaginal ultrasound is ordered to evaluate for many different diagnoses, including but not limited to possible pelvic mass, causes of pelvic pain, cause of abnormal bleeding, location of IUD or infertility problems. During a transvaginal ultrasound, the patient will lie of their back with their feet in stirrups, similar to the position for a pelvic exam. The transducer used for this ultrasound looks like a wand and is covered with a latex sheath that looks like a condom. The sheath is then lubricated with gel and inserted into the vagina where pictures of the uterus are taken.
A fetal ultrasound is performed to evaluate your baby’s growth and development. Measurements of the fetus’s head circumference, abdomen, thigh bone, and weight are taken to determine the gestational age of the fetus. Pictures of the fetus are taken, and the volume of amniotic fluid is measured. Note that ultrasound measurements may be incorrect up to 20 percent. Fetal ultrasounds can also be used to evaluate problems or help confirm a diagnosis.
A biophysical profile is a prenatal ultrasound performed to examine the well-being of the baby. Once the results are evaluated, a score is given out of 10 to determine if the baby is healthy. The machine evaluates the baby’s heart rate, movements, breathing, amniotic fluid level, and muscle tone. The test is performed to prevent pregnancy loss and ensure the baby’s oxygen levels are in a healthy range. This is typically performed after 32 weeks’ gestation but can be performed as soon as you are far enough along to deliver.
A transabdominal ultrasound is performed to examine the organs in the abdomen and structures in the female pelvis. In order to have the best window to see the organs, a full bladder is required. You will lie down on the exam table with your abdomen exposed. A gel will be applied to your abdomen and an external probe will scan the surface. Images will be taken on the machine and the organs and tissues will be evaluated