For the first 6 weeks, the baby is called an embryo. The heart, lungs, and brain are beginning to develop and the tiny heart will beat by the 25th day. The embryo is enclosed in a sac of fluid to protect it from bumps and pressure. The baby will grow in this sac until birth.
During this time you may not notice a weight gain, but your breasts may be larger and may feel tender. You may also have some "morning sickness" or nausea.
Visiting your doctor is very important during these early stages. Your doctor will perform several tests to check the health of both you and your baby. She will also be able to answer questions about any concerns or fears you might have, and she will tell you what you can do to make your pregnancy as easy as possible.
During this month the embryo becomes a fetus. It has arms with tiny hands and fingers. Legs, the beginnings of knees, ankles, and toes are all starting to form. Organs such as the stomach and liver a simple brain, spine and central nervous system have also begun to develop. Pits have formed which will become the baby's eyes and ears. You may tire more easily and need to urinate more frequently. You may also, still be experiencing some nausea.
It is very important to eat the right foods, because you and your baby are changing and growing every day and you both need proper nourishment.
By the end of this trimester, your baby will weigh approximately 30 grams, and be about 3 inches in length and signs of the baby's sex are beginning to appear. Finger and toe nails are developing. The facial features are becoming well defined, with an obvious chin, nose, and forehead. Eyes are fully formed and eyelids are developing. The baby is now starting to move the hands, legs, and head. At this point you will not feel the baby's movement. You may have gained about 1 to 2 kgs.
A few symptoms you may experience during the first trimester: