For some couples, arriving at the miracle of birth is more complex than sperm + egg = embryo = pregnant. The human body is incredibly complex, and few processes are as complicated as human reproduction.
For example, consider the first five days in the reproduction process:
Day 0 – Egg meets sperm in the fallopian tube. Sperm penetrates egg.
Day 1 – Fertilization occurs and a zygote forms, which includes DNA from both the male and female.
Day 2 – The zygote has evolved into an embryo. Cell count is now four.
Days 3 to 5 – Even more growing as the cells split. There are now eight cells. The embryo leaves the fallopian tube and enters the uterus.
Day 5– Embryo hatches, blastocyst embryo erupts and implants into the uterine wall, and a woman is deemed pregnant.