Final answer:
d) outside the uterine cavity. An ectopic pregnancy occurs when the embryo implants outside the uterine cavity, most commonly in the uterine tube. Scar tissue within the tube can block or hinder the progress of the embryo, leading to complications. Early detection is crucial for appropriate intervention.
Step-by-step explanation:
An ectopic pregnancy occurs when the embryo implants outside the uterine cavity. The most common site for an ectopic pregnancy is the uterine tube, also known as a tubal pregnancy. However, ectopic pregnancies can also occur in the ovaries and abdomen.
Tubal pregnancies are often caused by scar tissue within the tube, which can block or hinder the progress of the embryo. In some cases, an ectopic pregnancy may resolve spontaneously, but in others, medical or surgical intervention is necessary.
Early detection of an ectopic pregnancy is crucial. If diagnosed early, the embryo's development can be stopped using the cytotoxic drug methotrexate. However, if the uterine tube is already ruptured, surgical repair is essential.