What’s the difference?

FERTILISATION AND CONCEPTION

Fertilisation This occurs when a sperm meets and then penetrates an egg. When ovulation and intercourse overlap, sperm swim up through the cervix and uterus to meet the egg, and fertilisation with one sperm usually happens in the upper end of the Fallopian tube. The sperm cells and egg cells each have only 23 chromosomes. When they meet and fuse, the resulting fertilised cell has the full 46 chromosomes. Conception It takes up to seven days for the fertilised cell, the zygote, to reach the uterus and implant in the endometrium – the specially prepared uterine lining. The process of implantation is called nidation. The fertilised egg, now called a blastocyst, burrows into the lining and quickly forms a primitive placenta. Seven days after fertilisation, the blastocyst is embedded and growing.