Obstetric ultrasonography - online puzzles
Obstetric ultrasonography is the use of medical ultrasonography in pregnancy, in which sound waves are used to create real- time visual images of the developing embryo or fetus in its mother 's uterus (womb). The procedure is a standard part of prenatal care in many countries, as it can provide a variety of information about the health of the mother, the timing and progress of the pregnancy, and the health and development of the embryo or fetus.
The International Society of Ultrasound in Obstetrics and Gynecology (ISUOG) recommends that pregnant women have routine obstetric ultrasounds between 18 weeks' and 22 weeks' gestational age (the anatomy scan) in order to confirm pregnancy timing, to measure the fetus so that growth abnormalities can be recognized quickly later in pregnancy, and to assess for congenital malformations and multiple pregnancies ( twins, etc). Additionally, the ISUOG recommends that pregnant women have obstetric ultrasounds between 11 weeks' and 13 weeks 6 days' gestational age in countries with resources to perform them (the nucal scan). Performing an ultrasound at this early stage of pregnancy can more accurately confirm the timing of the pregnancy and can also assess for multiple fetuses and major congenital abnormalities at an earlier stage. Research shows that routine obstetric ultrasound before 24 weeks' gestational age can significantly reduce the risk of failing to recognize multiple gestations and can improve pregnancy dating to reduce the risk of labor induction for post-dates pregnancy. There is no difference, however, in perinatal death or poor outcomes for babies.
Terminology
Below are useful terms on ultrasound:
Echogenic — giving rise to reflections (echoes) of ultrasound waves
Hyperechoic – more echogenic (brighter) than normal
Hypoechoic – less echogenic (darker) than normal
Isoechoic – the same echogenicity as another tissue
Transvaginal ultrasonography – Ultrasound is performed through the vagina
Transabdominal ultrasonography – Ultrasound is performed across the abdominal wall or through the abdominal cavityIn normal state, each body tissue type, such as liver, spleen or kidney, has a unique echogenicity. Fortunately, gestational sac, yolk sac and embryo are surrounded by hyperechoic (brighter) body tissues.
Types
Traditional obstetric sonograms are done by placing a transducer on the abdomen of the pregnant woman.