Q.Briefly explain IVF and ET. What are the conditions in which these methods are advised?

IVF, or in-vitro fertilisation, involves fertilising the ovum with sperm outside the body in a laboratory dish. Once the fertilised egg develops into an 8-celled embryo, it is transferred into the female's uterus — this step is called ET, or embryo transfer.

These methods are advised when:

• The female partner has blocked or damaged fallopian tubes, preventing the egg from meeting the sperm naturally.
• The male partner has very low sperm count or poor sperm motility, making natural fertilisation unlikely. …

Assisted Reproductive Technology, or ART, covers a range of medical procedures designed to help couples who cannot conceive naturally. Among the most well-known of these are IVF and ET. IVF stands for in vitro fertilisation — literally, “fertilisation in glass” — meaning the union of sperm and egg takes place outside the woman’s body, in a laboratory dish. ET, or embryo transfer, is the step that follows: once the fertilised egg has developed into a tiny embryo (usually after a few days of growth), it is carefully placed into the woman’s uterus, where it may implant and continue developing normally.

The logic behind IVF and ET is straightforward. In natural conception, the egg is fertilised inside the fallopian tube, and the early embryo then travels down into the uterus. If something blocks that journey or prevents the sperm from meeting the egg, IVF bypasses the problem by bringing the two together in a controlled environment. The embryo is then transferred directly into the uterus, skipping any damaged or blocked tubes.

So when are these methods advised? The NCERT textbook specifies several clear conditions. IVF and ET are recommended primarily for couples where the woman has blocked or damaged fallopian tubes. If the tubes are scarred, blocked, or absent, the egg and sperm cannot meet naturally, and the embryo cannot travel to the uterus. IVF completely sidesteps this obstacle.

Another common indication is very low sperm count in the male partner. When the number of healthy, motile sperm is too small to achieve fertilisation inside the body, IVF allows a few selected sperm to be placed directly next to the egg in the dish, greatly increasing the chance of fertilisation. In some cases, a single sperm may even be injected into the egg — a related technique called ICSI (intracytoplasmic sperm injection). …