Final answer:
Transvaginal ultrasound is preferred for diagnosing placental previa because it provides a more detailed image of the cervix and placenta. Transabdominal US can be used as well but is generally less precise for this condition. Accurate diagnosis of placental previa is essential for managing potential complications during pregnancy.
Step-by-step explanation:
When diagnosing placental previa, both transabdominal and transvaginal ultrasound (US) can be utilized. A transabdominal US offers a less invasive procedure with a broader overview but may be less clear if the patient has a higher body mass index or if the bladder is not adequately filled. A transvaginal US, on the other hand, provides a more detailed image of the lower uterus and is preferred for diagnosing placental previa because it allows closer proximity to the cervix and placenta, which can reveal the condition with greater accuracy. Placental previa is a condition where the placenta partially or completely covers the cervix, which can lead to such complications as antepartum hemorrhage. In contrast to transabdominal US, transvaginal ultrasound can reveal the normal location of the placenta and placental previa with more precision due to the more direct imaging angle and closer distance to these structures. The typical incidence of placental previa is relatively low, occurring in only about 0.5 percent of pregnancies. Nonetheless, its diagnosis is vital for preventing potential complications. Ultrasound is essential in prenatal care, and reaching an accurate diagnosis is critical for the health of both mother and baby.