A nurse is reviewing the differences between placenta previa and abruptio placentae with a group of nursing students. Which of the following statements accurately differentiates placenta previa from abruptio placentae?

A. "Placenta previa usually results in a higher risk of maternal hypertension, while abruptio placentae is commonly associated with a low-risk pregnancy.
This is incorrect because abruptio placentae, not placenta previa, is associated with maternal hypertension (e.g., preeclampsia, chronic hypertension). Placenta previa is not related to blood pressure issues.

B. "Placenta previa is characterized by sudden onset of severe abdominal pain and uterine tenderness, while abruptio placentae is associated with painless bleeding."
This is incorrect because placenta previa presents with painless, bright red vaginal bleeding, while abruptio placentae causes sudden, severe abdominal pain, uterine tenderness, and possibly dark red bleeding.

C. "Placenta previa typically presents with severe pain and contractions, whereas abruptio placentae involves painless bleeding without contractions."
This is incorrect because placenta previa does not cause pain or contractions. In contrast, abruptio placentae often presents with painful contractions and uterine hypertonicity.

D. "Placenta previa involves the placenta partially or completely covering the cervix, whereas abruptio placentae involves the premature separation of the placenta from the uterine wall."
Placenta previa occurs when the placenta covers the cervix (partial or complete), leading to bleeding. Abruptio placentae occurs when the placenta prematurely separates from the uterine wall, which can lead to hemorrhage and fetal distress.

A. Passage of fetal tissue – This finding is more consistent with an incomplete or complete abortion, not a threatened abortion.

B. Bright red vaginal bleeding – A threatened abortion involves vaginal bleeding during the first 20 weeks of pregnancy, often bright red in color. The cervix remains closed, and fetal cardiac activity may still be present.

C. Severe cramping and pelvic pain – Severe pain is more typical of an inevitable or incomplete abortion rather than a threatened abortion.

D. Closed cervix upon examination – In a threatened abortion, the cervix remains closed. If the cervix opens, the risk of progressing to an inevitable abortion increases.

E. Mild to moderate lower abdominal cramping – Mild cramping or lower abdominal discomfort is common in a threatened abortion due to uterine contractions. However, severe cramping and passage of fetal tissue would indicate a more advanced pregnancy loss.