Which description accurately defines placenta previa?

Which description accurately defines placenta previa?

• A. The placenta attaches to the upper uterus away from the cervix.
• B. The placenta implants near the lower uterine segment and may cover the cervical os, causing painless bright red bleeding.
• C. The placenta detaches early causing bleeding and pain.
• D. The placenta forms abnormally leading to joint issues.

Answer: (B)

Placenta previa occurs when the placenta implants in the lower uterine segment near or over the cervix. Its location can block the cervical opening or be close enough that placental vessels can bleed into the vagina without contractions, leading to painless, bright red vaginal bleeding in the second or third trimester. This is typically diagnosed by ultrasound and often requires delivery by cesarean if the placenta covers the os, since vaginal delivery could be unsafe. The description described fits this pattern: implantation near the lower uterus and potential coverage of the cervical os with painless bleeding. In contrast, the other scenarios reflect placental abruption (painful bleeding with uterine pain) or normal placentation, not previa, or describe non-placental issues.

Placenta previa occurs when the placenta implants in the lower uterine segment near or over the cervix. Its location can block the cervical opening or be close enough that placental vessels can bleed into the vagina without contractions, leading to painless, bright red vaginal bleeding in the second or third trimester. This is typically diagnosed by ultrasound and often requires delivery by cesarean if the placenta covers the os, since vaginal delivery could be unsafe. The description described fits this pattern: implantation near the lower uterus and potential coverage of the cervical os with painless bleeding. In contrast, the other scenarios reflect placental abruption (painful bleeding with uterine pain) or normal placentation, not previa, or describe non-placental issues.