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Week 1 & 2
The Zygote is formed which is the set of 46 chromosones. If conception takes place, the sperm penetrates an egg and creates a single set of 46 chromosomes called a zygote, which is the basis for a new human being. The fertilized egg spends a couple days traveling through the fallopian tube toward the uterus, dividing into cells ; it is called a morula. The morula becomes a blastocyst and will eventually end up in the uterus. Anywhere from day 6-12 after conception, the blastocyst will imbed int -
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Development of Baby
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Week 3
The embryo is going through lots of basic growth at this time, with the beginning development of the brain, spinal cord, heart, and gastrointestinal tract. -
Week 4 & 5
Arm and leg buds are visible, but not clearly distinguishable. The heart is now beating at a steady rhythm. The placenta has begun to form and is producing some important hormones including hCG. There is movement of rudimentary blood through the main vessels. The early structures that will become the eyes and ears are forming. The embryo is ¼ inch long by the end of these weeks. -
Week 6
The formation of the lungs, jaw, nose, and palate begin now. The hand and feet buds have webbed structures that will become the fingers and toes. The brain is continuing to form into its complex parts. A vaginal ultrasound could possibly detect an audible heartbeat at this time. The embryo is about a ½ inch in length. -
Week 7
At 7 weeks gestation, every essential organ has begun to form in the embryo’s tiny body even though it still weighs less than an aspirin. The hair and nipple follicles are forming, and the eyelids and tongue have begun formation. The elbows and toes are more visible as the trunk begins to straighten out. -
Week 8
The ears are continuing to form externally and internally. Everything that is present in an adult human is now present in the small embryo. The bones are beginning to form, and the muscles can contract. The facial features continue to mature, and the eyelids are now more developed. The embryo is at the end of the embryonic period and begins the fetal period. The embryo is about 1 inch long and is the size of a bean. -
Week 9-13
The fetus has grown to about 3 inches in length and weighs about an ounce. The genitalia have clearly formed into male or female, but still could not be seen clearly on an ultrasound. The eyelids close and will not reopen until the 28th week of pregnancy. The fetus can make a fist, and the buds for baby teeth appear. The head is nearly half the size of the entire fetus. -
Beggining of the Second Trimester Week 14-16
The fetus’s skin is transparent and a fine hair called lanugo begins to form on the head. The fetus begins sucking and swallows bits of amniotic fluid. Fingerprints which individualize each human being have now developed on the tiny fingers of the fetus. Meconium is made in the intestinal tract and will build up to be the baby’s first bowel movement. Flutters may be felt in the mom’s growing abdomen as the fetus begins to move around more. Sweat glands have developed, and the liver and pancreas -
Week 17-20
The baby has reached a point where movements are being felt more often by the mom. The eyebrows and eyelashes grow in, and tiny nails have begun to grow on the fingers and toes. The skin of the fetus is going through many changes and begins to produce vernix at the twentieth week. Vernix is a white pasty substance that covers the fetus’s skin to protect it from amniotic fluid. A fetal heartbeat could be heard by a stethoscope now. The fetus has reached a length of 8 inches and weighs about 12 ou
