What is the process by which an embryo at the blastocyst stage extrudes out of, and ultimately separates from, the zona pellucida?

What is the process by which an embryo at the blastocyst stage extrudes out of, and ultimately separates from, the zona pellucida?

• A. Hatching
• B. Hydrosalpinx
• C. Hypospermia
• D. Latrogenic testicular failure

Answer: (A)

Hatching is the process by which the embryo, at the blastocyst stage, extrudes from the zona pellucida so it can implant in the endometrium. The zona pellucida is a protective shell around the developing embryo. As the blastocyst expands, it applies pressure against this shell, and the trophoblast cells secrete enzymes that weaken it. The combination of thinning and weakening allows the zona to rupture, freeing the hatched blastocyst so it can attach to and invade the uterine lining. The other terms describe unrelated conditions: hydrosalpinx is a fluid-filled fallopian tube blockage, hypospermia is low semen volume, and iatrogenic testicular failure refers to medical-induced testicular dysfunction.

Hatching is the process by which the embryo, at the blastocyst stage, extrudes from the zona pellucida so it can implant in the endometrium. The zona pellucida is a protective shell around the developing embryo. As the blastocyst expands, it applies pressure against this shell, and the trophoblast cells secrete enzymes that weaken it. The combination of thinning and weakening allows the zona to rupture, freeing the hatched blastocyst so it can attach to and invade the uterine lining. The other terms describe unrelated conditions: hydrosalpinx is a fluid-filled fallopian tube blockage, hypospermia is low semen volume, and iatrogenic testicular failure refers to medical-induced testicular dysfunction.