In vitro fertilization IVF is the joining of a woman's egg and a man's sperm in a laboratory dish. In vitro means outside the body. Fertilization means the sperm has attached to and entered the egg. Normally, an egg and sperm are fertilized inside a woman's body. If the fertilized egg attaches to the lining of the womb and continues to grow, a baby is born about 9 months later.
Pregnancy - identifying fertile days: MedlinePlus Medical Encyclopedia
Watch a human sperm under a microscope, and it will appear to swim like an eel wiggling its tail through the water. Researchers scanned human sperm samples with a 3D microscope and a high-speed camera—one that could keep up with the speedy swimmers, which can manage 20 to 30 swimming strokes per second. Though in two dimensions sperm appear to lash their tail from side-to-side in symmetric strokes, the reproductive cells actually move in a lop-sided manner , beating their tails to one side only as seen in the video above , the team reports today in Science Advances. This movement should cause the sperm to swim around in circles, but they have found a solution that allows them to propel forward, the team found. Their heads spin in one direction, while the tail rotates around it in the opposite direction in a process known as precession—much like Earth spinning on its axis while orbiting the Sun. This corkscrewing motion balances out in an overall forward trajectory, creating the illusion of symmetry from asymmetry. Subtle changes in sperm movement could affect fertility, the team notes, so these findings could pave the way toward new fertility treatments or even a male contraceptive that could target sperm mobility.
When trying to become pregnant, many couples plan intercourse between days 11 to 14 of the woman's day cycle. This is when ovulation occurs. It is hard to know exactly when ovulation will happen.
Back to Pregnancy. Yes, although the risk of getting pregnant in this way is very low. If you want to avoid getting pregnant, you should use contraception. A man's semen the liquid produced when he ejaculates or "comes" contains millions of sperm.