About five days after conception, implantation occurs. Once the embryo, now called a blastocyst, reaches the uterus, it searches for a nice place to implant. Then it burrows beneath the surface of the uterus and its cells begin to divide into two groups: those that form the placenta and those that form the baby.
Your embryo is the size of a raisin (only 1/10 of an inch or 1.5-3 mm).
By day twenty-one, the embryo's tiny heart has begun beating. The neural tube enlarges into three parts, soon to become a very complex brain. The placenta begins functioning. The spine and spinal cord grows faster than the rest of the body at this stage.
Now your embryo is working very hard to begin growing its nervous system. There's a primitive heart now, and just wait until it can show you its love! Tiny buds have appeared -- if all goes well, these will someday be arms to hug you and legs to kick at you during temper tantrums. By now, your baby displays reflexes in response to a touch!
This means his nervous system is communicating with his primitive muscle cells. This communication forms the foundation of all your baby's behavior even after birth.
By day 30, facial features are visible, including a mouth and tongue. The eyes have a retina and lens. The major muscle system is developed, and the unborn child practices moving. The child has its own blood type, distinct from the mother's. These blood cells are produced by the liver now instead of the yolk sac.
Your embryo is about 8mm long, and an ultrasound done now would detect the tiny thumping of the heart. Although all her major organs have formed, they are not fully developed or functional.
So to back up, THIS is the first trimester.
4 weeks - The embryo produces hormones which stop the mother's menstrual cycle.
5 weeks - Embryo is the size of a raisin. By day twenty-one, the embryo's tiny heart has begun beating. The neural tube enlarges into three parts, soon to become a very complex brain. The placenta begins functioning. The spine and spinal cord grows faster than the rest of the body at this stage and give the appearance of a tail. This disappears as the child continues to grow.
7 weeks - Facial features are visible, including a mouth and tongue. The eyes have a retina and lens. The major muscle system is developed, and the unborn child practices moving. The child has its own blood type, distinct from the mother's and the child's gender is determined. These blood cells are produced by the liver now instead of the yolk sac.
8 weeks - The unborn child, called a fetus at this stage, is about half an inch long. The tiny person is protected by the amnionic sac, filled with fluid. Inside, the child swims and moves gracefully. The arms and legs have lengthened, and fingers can be seen. The toes will develop in the next few days. Brain waves can be measured.
10 weeks - The heart is almost completely developed and very much resembles that of a newborn baby. An opening the atrium of the heart and the presence of a bypass valve divert much of the blood away from the lungs, as the child's blood is oxygenated through the placenta. Twenty tiny baby teeth are forming in the gums.
12 weeks - Vocal chords are complete, and the child can and does sometimes cry (silently). The brain is fully formed, and the child can feel pain. The fetus may even suck his thumb. The eyelids now cover the eyes, and will remain shut until the seventh month to protect the delicate optical nerve fibers.
To repeat. By the end of 12 weeks, not 12 weeks after conception, but 12 weeks after the beginning of the entire pregancy, which would make the fetus only 10 weeks old, could YOU murder a child who has already proven its readiness for survival by becoming a wee small version of you or his/her mother? Whose brain is functioning? Who can feel pain and cry?
This is 18 weeks after the onset of pregnancy, not conception. It doesn't look human enough for you?
You are very rude, but that is usually what people resort to when they run out of answers and reason. Have fun while you wonder how much fun murdered infants have...