Baby developing inside you
over the weeks and months
Month 1: Embryo starts to grow
About 5 to 7 days after a sperm fertilizes an egg, the egg attaches to the lining of the uterus.
This process is called implantation The fertilized egg then begins to grow in the uterus, doubling in size every day.
Finger-shaped growths called chorionic villi grow into the uterine wall to anchor the embryo. Your baby is about the size of a pea! Shortly after implantation the placenta and umbilical cord begin to form. The placenta and umbilical cord provide nourishment and oxygen to your baby and carry away the baby's wastes. Your baby is enclosed in a sac of fluid, called the amniotic sac, to protect the baby from bumps and pressure.
In another week the baby has a spinal cord. A few days later, five to eight bones of the spinal column (vertebrae) are in place. Nerve development is beginning.
The embryo becomes three layers around the 5th week. The outer layer consists of the brain, nerves, and skin. The middle layer becomes the bones, muscles, blood vessels, heart, and sex organs. The inner layer holds the stomach, liver, intestines, lungs, and urinary tract. The eyes and other features begin to form, as do tiny buds that will be the arms and legs. The heart also forms, and it begins to beat on the 25th day after conception (5 to 6 weeks after the last menstrual period). The heart beat can already be detected, however, it is impossible to hear the heart beating at this time.
By the end of the first month, your unborn baby is technically known as an embryo.
By the end of your first 6 weeks of pregnancy, your baby has a head and trunk, and is about 1/4 inch long (8 mm) and weighs a fraction of an ounce (or a few grams).
* nausea, and not just in the morning
If you suspect you're pregnant, you can try a home pregnancy test (about 95% accurate) or make an appointment with your doctor or health care provider, for a hCG blood test or pelvic exam to confirm your pregnancy. The sooner your pregnancy is confirmed, the sooner you can begin prenatal care.
The first weeks are the most vulnerable for an unborn baby, so it's a good time to assess your lifestyle. Stop smoking and cut down on alcohol, check your work environment for hazardous conditions, and take care when handling pets to avoid contracting toxoplasmosis.
Avoid changing cat litter for there is a risk of toxoplasmosis. Let someone else do this duty for while. Toxoplasmosis can cause genetic defects, but most women who have cats have already had toxoplasmosis, and just believed it to be the flu. So don't get rid of the cat, just let someone else change the litter.
Week by week: First trimester ultrasound scan pictures
Month 2 >>>