How many sperms need for test tube baby?

For a test tube baby, also known as in vitro fertilization (IVF), typically only one sperm is needed to fertilize one egg. However, multiple sperm are often collected to increase the chances of successful fertilization, as not all sperm will successfully penetrate the egg. In some cases, intracytoplasmic sperm injection (ICSI) is used, where a single sperm is directly injected into an egg to facilitate fertilization. Overall, the number of sperm used can vary depending on the specific IVF technique and the individual circumstances.