Weeks 1 to 3 are the first weeks of pregnancy. Week 1 begins on the first day of your last menstrual period. You will have no pregnancy symptoms yet, it's too early right now. By week 4 nearly all of the organs and structure of the fetus have formed, you will start to feel the first pregnancy symptoms which will feel a bit like period symptoms such as tiredness and tender breasts.

Weeks 5/6/7. By now mother's breast have swelled and are sensitive as milk glands multiply. Morning sickness will kick in and your appetite will increase. The embryo has developed the heart and primitive circulatory system. The first heartbeats begin and facial features begin to develop. Cravings might start and be expected to gain or loose a few pounds over these few weeks. Your uterus is putting pressure on your bladder so be prepared for frequent visits to the ladies.

Weeks 8/9/10. You can have an Ultra sound now and your uterus has grown to the size of a small grapefruit. The baby's fingers and thumbs have now appeared and teeth are developing under the gums. Your breasts are fuller than ever before this maybe uncomfortable, a maternity bra can help.

In the tenth week the baby may begin to move inside the womb and most of the joints are formed. Morning sickness will ease and your blood volume may increase by 40 to 50% resulting in prominent veins mostly on the tummy, breasts and legs.

Weeks 11/12/13. The most critical part of the baby's development is over. The genitals will begin to take on their gender characteristics and your uterus will move upwards, this will take pressure off the bladder. Light-headedness and headaches can be expected thanks to the increased blood volume, this is normal but make sure to discuss these and any other symptoms with your doctor.

Week 13 is the beginning of your half way point (weeks 13 to 27). This is a very busy week indeed for the baby's development. The vocal cords develop and the baby's facial features are beginning to look more human. The intestines move further into the baby's body, the liver begins to secrete bile and the pancreas produces insulin. Most of the early pregnancy symptoms are over, though you may feel some abdominal pain due to the stretching of the uterus.

Weeks 14/15/16. The baby is about 3 to 4 inches long and is beginning to practice inhaling and exhaling movements. By now pregnancy hormones are leveling off. This means less nausea, less frequent urination and less tiredness. Constipation may become a problem due to those darned hormones so be sure to increase your fibre intake. Also the areolas of your breasts may be growing in diameter and darkening, this is in preparation for breastfeeding.

If you have an ultra sound now you will probably see the baby sucking its thumb. A fine hair called Lanugo is growing all over it's body.

Your uterus is now ascending above your hipbones and your doctor will begin to measure "fundal height" to make sure your baby is growing adequately. At week 16 you will begin to feel movement as the baby's bones harden, fingernails and toenails begin to grow too.

The rising of estrogen levels may cause inflammation of your nasal membranes resulting in nosebleeds. Keep in mind that if you are planning to have an amniocentesis this may be scheduled between 16 and 18 weeks.

Weeks 17/18/19. The baby's heart is pumping as much as 25 quarts of blood per day. The reflexes are in place as the baby sucks, swallows and blinks. "Meconium" the baby's first bowel movement is accumulating within the bowel. If you feel jerky movements this could be due to the baby hiccupping. It is possible to determine sex at this stage. Average weight gain for mum is between 5 and 10 pounds at this point.

You could be experiencing several skin changes at this stage including blotchy patches and dry itchy skin is common. Remember you cannot prevent stretch marks but oils and lotions may help ease the discomfort of dry itchy skin. Also drinking plenty of water will help hydrate dry skin.

Weeks 20 to 27. You are half way through the pregnancy and it's probably a good time to look into childbirth classes. The baby's growth may have slowed down but you may have put on 10 to 20pounds. You are feeling emotionally more stable and comfortable, your ankles and feet may swell so keep them elevated and drink plenty of water. The baby will grow from one to two pounds in these weeks and will be moving about a lot, you will probably see your abdomen move.

Your uterus will grow to the size of a football within this period and this will put pressure on your back and legs so rest as much as you can.

At week 26 you may experience 'Braxton hicks' contractions, these are similar to cramps it is your body's way of practicing for laybor. By week 27 your uterus is close to you rib cage and you may feel a shortness in breath due to your lungs not being able to fully expand, don't worry though this is normal.

The Final Straight weeks 28 to 40

During these last weeks of pregnancy the baby and mother get a lot heavier causing discomfort for mother. There will be a lot of growth and movement in the uterus. The growth of the uterus puts a lot of pressure on all the other organs in the body causing heartburn indigestion, hemorrhoids, varicose veins, and lots of aches and pains. Due to the rapid growth of the baby your levels of calcium and nutrients will be low so make sure your diet consists of plenty of calcium, protein, iron and folic acid.

Drink plenty of water and eat a lot of fibre rich foods or take some fibre supplements, this should ease constipation. Be sure to look after yourself and rest as much as possible in preparation for birth. Mood swings and blue feelings can be common, but don't be too hard on your self after all your body is going through an enormous change. So take care and try to relax, as your life is about to change forever with the arrival of this new little person in your life.

About the Author
Declan Tobin is a successful freelance writer providing advice for parents and consumers on purchasing a variety of baby products which includes baby crib bedding, strollers, and more! His numerous articles provide a wonderfully researched resource of interesting and relevant information.