A living passage, not a rigid pipe
A fallopian tube is narrow, but it is not an empty, straight straw. Its inner surface is folded and lined with cells bearing tiny hairlike structures called cilia. The tube’s muscular wall also contracts. Together, these motions help guide an egg toward the uterus; the egg itself cannot swim.
Near the ovary, fingerlike ends of the tube help collect the egg after it is released. The tube does not form a sealed connection to the ovary, so this pickup is a coordinated process rather than a simple handoff through an attached opening.
Where the journey can change course
Fertilization usually happens in the wider middle portion of the tube, not after the egg reaches the uterus. If sperm meets the egg, the resulting early embryo continues toward the uterus while the tube’s cilia and contractions move it along. The passage is therefore both a route and a temporary environment for the earliest stage of development.
That role helps explain why a blockage or damage in a tube can affect fertility: sperm and egg may not meet, or an embryo may not reach the uterus normally. If an embryo implants in the tube instead, it is an ectopic pregnancy. Because the tube cannot safely accommodate a growing pregnancy, this can become a medical emergency.
