It's surprising how little we seem to know about the processes which take place inside our body. This is a shame as our body performs mind blowing amazing things everyday, the most perfect living machine and a total miracle in design. For those of you trying to get pregnant, for those of you I am giving fertility enhancing Arvigo sessions to and for those just interested in the workings of our body, here is a short summary of the journey of the egg to embryo.
Each month inside an ovary, alternating in monthly cycles, a group of eggs start to grow in small, fluid-filled sacs called follicles. Eventually, one of the eggs erupts from the follicleas a mature egg, a process called ovulation.
After the egg leaves the follicle, the follicle develops into something called the corpus luteum, which releases a hormone which helps to thicken the lining of the uterus, preparing it for the egg.
The egg then travels into the fallopian tube. Here it must be fertilised by a single sperm within 12-24 hours otherwise the egg dies and is shed with the uterus lining in a process we know as menstruation.
All this happens, on average, about 2 weeks after your last period.
If you’re trying to conceive, it’s more important to know when your fertile window is, rather than when you actually ovulate. Luckily, the fertile window lasts a lot longer than ovulation itself because sperm can live inside the female reproductive tract for up to five days. The best chance for pregnancy occurs when sperm is waiting in the fallopian tubes before ovulation occurs.
A man may ejaculate 40 million to 150 million sperm, which start swimming upstream toward the fallopian tubes on their mission to fertilise an egg. Fast-swimming sperm can reach the egg in a half an hour, while others may take days. The sperm can live up from 48-72 hours and only a few hundred will even come close to the egg because of the many natural barriers that exist in a woman's body.
When the sperm penetrates the egg, the surface of the egg changes so that no other sperm can enter. At the moment of fertilisation, the baby's genetic makeup is complete, including whether it's a boy or girl.
The fertilised egg starts growing and, dividing into many cells. It leaves the fallopian tube and enters the uterus 3 to 4 days after fertilisation. In rare cases, the fertilised egg attaches to the fallopian tube, called a tubal pregnancy or ectopic pregnancy.
After the egg reaches the uterus, the fertilised egg attaches to the lining of the uterus, called the endometrium. This process is known as implantation. After the egg attaches to the uterus, some cells become the placenta while others become the embryo. Some women notice spotting (or slight bleeding) for 1 or 2 days around the time of implantation. The lining of the uterus gets thicker and the cervix is sealed by a plug of mucus which will stay in place until the baby is ready to be born.
Within about a week of conception, a hormone called human chorionic gonadotropin (hCG) can be found in the mother's blood, made by cells that have become the placenta. The hormone will show up on a blood or urine pregnancy test at the doctor's office. But it usually takes 3 to 4 weeks for levels of hCG to be high enough to be detected by home pregnancy tests.
The heart begins beating during week 5. The brain, spinal cord, heart, and other organs are beginning to form. At the eighth week the developing baby, now called a foetus, is well over a half-inch long -- and growing. A "full term" delivery generally happens around 40 weeks.
Fascinating 3 minute video of the journey from conception to birth.