Which of the following best describes in vitro fertilization?

• A. Fertilization occurs outside the body with embryo transfer into the uterus
• B. Fertilization occurs inside the body
• C. Extraction of sperm without egg
• D. Surrogate birth

Answer: (A)

IVF describes fertilization happening outside the body, in a laboratory, with the resulting embryo then being transferred into the uterus. Eggs are retrieved and combined with sperm in a dish, allowing fertilization to occur in vitro. The embryo is cultured for a few days and, once ready, placed into the uterus to implant. This sequence is what sets IVF apart from natural conception, where fertilization occurs inside the body, and from other concepts like simply extracting sperm without an egg or surrogate birth, which involve different processes. IVF is used to overcome various infertility factors by enabling fertilization in a controlled lab environment and then advancing the embryo to implantation in the uterus.