Which assisted reproductive technology involves the maturation and fertilization of the egg within laboratory glassware, followed by transfer of the embryo to the uterus 2–4 days later?

It is in vitro fertilization (IVF).
IVF is a type of assisted reproductive technology used for infertility treatment. It includes the steps like removing an ovum from the woman's ovaries, fertilisation (sperm cell from is injected using a microscopic needle, directly into each harvested ovum from the woman) outside the body, embryo transfer to the same or another woman's uterus after a few days.