Conception or fertilization usually occurs in the middle of your cycle i.e day 14 if you have a 28 day menstrual cycle. If conception has taken place, you may notice either your menses is delayed or you experience minimal vaginal spotting. This is called implantation bleeding. After the egg is being fertilized, it begins to travel down the fallopian tube to the womb to be implanted. The formed embryo burrows itself into the uterine wall which may lead to vaginal bleeding. Some women will think that she was having her menses and may not realize she was already pregnant.

At conception, the sperm and egg each will provide 23 chromosomes which combines into 46 chromosomes. This combination of chromosomes is a complete genetic make-up forms a cell which will then start to divide rapidly into a collection of cell known as a blastocyst. The blastocyst will later on form the embryo. One week after conception, the embryo will implant itself into the uterine wall and divide into several layers, some will form the fetus the other the placenta.

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