Your baby is a about the size of an orange by pregnancy week 15, between 4 and 4 and ½ inches long and weighing more than 1 ½ ounces. This week your baby will start producing lanugo, which is fine hair that will cover your baby's body up until a few weeks before birth.

Your baby's bones are starting to get harder during pregnancy at 15 weeks and will continue to do so throughout your pregnancy. Your baby is spending most of his time practicing breathing, by inhaling and exhaling amniotic fluid. This helps your baby's air sacs develop during pregnancy.

Your baby continues to form taste buds at this point in time. Your baby’s legs are longer than his arms at this point. Eyebrows and hair may appear, and if your baby is going to have dark hair the hair cells which color it will start to produce their color.

By this week, some fine hairs have developed on your baby’s face. This soft colorless hair is called lanugo, and it will eventually cover most of your baby’s body until it is shed just before delivery.

By now, your baby’s genitals have fully developed, though they may still be difficult to detect on an ultrasound examination. In addition, your baby starts to produce thyroid hormones because the thyroid gland has matured. Your baby now weighs about 1.6 ounces (45 grams) and is about 3.5 inches (9 cm) long from crown to

Week 13 marks a milestone for your baby-to-be. Developmentally speaking she's no longer an embryo, but a fetus. She's looking—and acting—more and more like a baby every day. She appears to be resting because her eyelids have formed and are fused together, but her arms and legs move and twitch (although you probably can't feel it … yet). She can suck her thumb, too.
Your baby is about the size of a egg! She's growing heavier at around .5 to .8 ounces and is getting longer at about 3 inches long (crown to rump).

At 12 weeks pregnant, the placenta is much larger and now produces the endocrine secretions, or hormones, needed to sustain the pregnancy. The uterus is the size of a grapefruit that completely fills the pelvis and rises up into the abdominal cavity, as shown in the picture above. The fundus, the upper end of the uterus, is just above the top of the symphysis. This upward growth of the uterus takes pressure off the bladder and decreases the need for frequent urination. The mucus plug fills the cervical canal.

By this week, the baby has fingernails and toenails and can open and close the fingers. Even though the baby starts to move its hands, legs, and head, you will not feel any movement yet. The baby is now about 3 inches long and weighs about 1 ounce

The baby can now move his or her arms around and it can also move around in the uterus. The baby's iris begins to develop and there are signs of fingernails. Your baby will weigh between 7 and 8 grams.

Week 11 to week 20 are a period of expeditious growth for the little one. He / She will grow in size from approximately 1.7 - 2.4 inches (44-60mm) to 6 inches (16cm). The urinary system is now fully functional and all the other major organs are now formed. The Fetus now measures about 1.9 in / 50 mm.

The Ears have started to move upward into their final position.

The Eyelidshave been developing and are currently sealed closed. They will stay like this tell about the 26th week.

The Neck is lengthening allowing the fetus to move its head.

The Diaphragm has developed and is able to move.

The Placenta is now circulating food and waste and will continue to grow larger as the pregnancy progresses.

The Ovaries or Testes are starting to develop.

The Embryo now measures about 1.19 in / 30 mm.

The Yolk Sacwill not be needed going forward as the placenta takes over.

The Placenta is now fully developed and will be your baby's lifeline going forward.

The Ears have formed the outer portion but still need to move upward into their final position.

The Umbilical Cord exchanges blood between the placenta and your baby.

The Wrists are now able to bend.

The Fingers & Toes have grown and separated.

The Intestines are developing at the base of the umbilical cord. This pregnancy week will show that your baby's brain is developing rapidly right now. A prenatal ultrasound would reveal well formed arms and legs as well as fingers and toes. Fetal development is occurring at a rapid pace now. During this pregnancy week, your baby will begin to kick his little feet and even open his mouths. In addition, your baby's intestines may begin to move into his body.

Your new resident is nearly an inch long — about the size of a grape — and weighs just a fraction of an ounce. She's starting to look more and more human. Her essential body parts are accounted for, though they'll go through plenty of fine-tuning in the coming months. Other changes abound: Your baby's heart finishes dividing into four chambers, and the valves start to form — as do her tiny teeth. The embryonic "tail" is completely gone. Your baby's organs, muscles, and nerves are kicking into gear. The external sex organs are there but won't be distinguishable as male or female for another few weeks. Her eyes are fully formed, but her eyelids are fused shut and won't open until 27 weeks. She has tiny earlobes, and her mouth, nose, and nostrils are more distinct. The placenta is developed enough now to take over most of the critical job of producing hormones. Now that your baby's basic physiology is in place, she's poised for rapid weight gain.

The Embryo now measures about 0.50 in / 12.9 mm.

The Yolk Sac is rapidly shrinking as the placenta starts to deliver nourishment to the embryo.

The Umbilical Cord is starting to provide the early stages of circulation.

The Ears are just starting to form the outer ear.

The Eyes are growing larger and getting darker.

The Hands & Feet are starting to develop fingers and toes that are still connected. Your baby is now a fetus! Veins are very visible beneath your fetus' skin and fingers and toes are forming now during this week of pregnancy. Your fetus is developing intestines, although amazingly enough—they are developing outside of your baby's body and in the umbilical cord. When your baby is big enough, they will move inside the body where they belong!!

You are 2 months pregnant already! Some of your clothes may begin to feel a bit tight during this week of pregnancy, and you may notice that you have already started to gain weight. Most doctors recommend that during pregnancy, women should gain between 20-30 pounds. Watch your diet closely and make sure that you are getting adequate nutrition to nourish both you and your baby during your pregnancy.

By pregnancy week 7 your baby grows in length up to 13 mm! Your baby is now closer to the size of a small raspberry than a kernel of corn! Pregnancy week 7 is an important time in the growth and development of your baby. By 7 weeks pregnant your baby's facial features start to take shape. If you were to peer at your baby very closely by pregnancy week 7 you could actually start seeing a tiny mouth. Inside this mouth your babies tongue is starting to take shape. By 7 weeks pregnant your baby's eyes also start taking on a more natural appearance, as the retina begins to shape and form. Your baby's muscle and bone systems continue to develop at pregnancy 7 weeks as well.

Your baby's body is even developing at a rapid pace during 7 weeks of pregnancy. Along with this your baby's intestines, appendix and thin veins start to take shape and form. All the while your baby is happily bouncing about in his warm and cozy nesting place.

Compared to the pregnancy week 5, your baby will appear big in pregnancy week 6 but definitely not bigger. The baby's growth is continues and your doctor will see the exact growth of your baby with an ultrasound. The length of your baby will be anything between 2 mm to 5 mm. This length is measured from the head of the baby to its buttocks and it is called as "crown-rump length". In pregnancy week 6 the ultrasound will clearly show you dark spots at the places where your baby's eyes and nostrils will come. Also you will get to see small holes in head, where later on your baby's ears will form. Also you will get to see tiny bud like structure where your baby's hands and leg will get formed.

The baby's heartbeats will also be clearly heard and the heart will beat about 100 to 140 times every minute. The blood will also get circulated inside the body of your baby. But it is not the case with all pregnancies. In some cases the heartbeats will be heard more clearly from the 7th week onwards. Your weight will start increasing rapidly from the pregnancy week 6. In the first trimester itself, you will gain about 5 pounds of weight. But this is also not fixed for all the pregnancies. If you are having severe nausea and morning sickness then you will not gain much weight at least in the first trimester. Hence don’t be surprised if you loose some weight.