Your pregnancy - week 2
It is 2 weeks since the last period started (or the beginning of week 3). It is around this time that your baby is conceived and a new life begins! The woman releases her mature egg (called ovulating) and if sperm are present in her fallopian tubes, there is a 20 to 25% chance her egg will be successfully fertilised to create a baby.
Once released, the egg becomes surrounded by thousands of sperm (called spermatozoa). Several stronger sperm burrow their heads into the egg's thick, outer covering. When the most determined sperm reaches the inner part of the egg first, a chemical reaction takes place, which automatically changes the egg's covering to make it impenetrable to other sperm.
At the same time the thrashing tail of the successful sperm detaches, leaving only its head within the egg. Combined they are now called the 'conceptus'.