How big is my baby?
At the start week 7 your baby measures about 4-5mm (0.16-0.2 inches) in length. By the end of the week, the crown rump measurement has increased to about 11-13mm (0.44-0.52 inches) - about the size of a pea.
How does my baby develop this week?
This week your baby grows quite significantly. Growth during week 7 is related to the on-going development of your baby's internal systems, organs and body.
The neural tube closed at your baby's head last week. This week it develops and begins to form the brain. Throughout week 6, the various regions and chambers of the brain continue to grow and further define. During this process your baby's head is pushed forward and becomes rounder. The eyes and ears look like little pits on the side of the head, and the nasal cavities and mouth are forming.
Your baby's heart has started to develop and begins to form the valves. Circulation has started to form and nerves also begin to grow. The two buds that will become the lungs are growing. The intestines and digestive system begin to take shape, dividing to create the oesophagus, stomach and small intestine. Other glands and organs also start to develop and the beginnings of the reproductive system are present.
Limbs are visible by week 7, and development of arms and legs progresses to the point where Hands, arms and shoulders start to form, and ridges, or digital plates indicate future fingers and toes. The umbilical cord is also present and has been sealed off within the wall of the amniotic sac that surrounds your baby. By the end of the week a smooth outer layer of skin develops.
What is happening to my body?
There are many changes occurring within your body, and while you're probably waiting to see some outer signs that show your pregnancy, there are no external signs at this point.
Despite the fact that there are no visible external signs of pregnancy, your hormones have increased and changed in order to sustain your pregnancy. As a result there are other noticeable effects. Other physical changes of pregnancy can include:
Increased vaginal discharge - this is due to hormone increases but should not be accompanied by any soreness or irritation.
Tiredness - it is quite common to feel tired, especially in the early stages of pregnancy. It's important to get as much rest as possible.
Breast changes - this can be an early sign of pregnancy, as the breasts become tender and sore due to increased blood supply and hormone changes. Some women can notice the appearance of more prominent veins on their breasts. Some can experience an increase in nipple sensitivity.
Morning sickness - Morning sickness can occur at any time of the day and affects women to varying degrees. It usually starts at around Week 5. There are many variations to morning sickness, from mild nausea in the mornings to vomiting following meals. In the majority of pregnancies, morning sickness eases around Week 12 but in some cases it can continue to Week 16. It is thought to occur due to hormone increases. The recommended management of morning sickness includes frequent small meals (5-6 per day), avoiding fatty, greasy or oily foods (you will soon discover the foods that you can't tolerate). If the nausea occurs later in the day, preparing meals in the morning will ensure you don't exacerbate the nausea. A drink and a biscuit or piece of toast before getting out of bed in the mornings may also help. If vomiting persists and is severe, you should contact your health care professional.
Constipation - this often occurs early in pregnancy and may last until after the baby is born. It is caused by hormone changes that slow down the bowel movements. Drinking plenty of water and eating high fibre foods, like fruit, vegetables, and wholemeal breads will help.
Headaches - this is a common complaint during pregnancy and is also related to hormone changes. It is best to seek advice of your health care professional if headaches persist. Analgesics (pain killers) and rest are often prescribed. Most health professionals will advise that it is OK to take Paracetamol during pregnancy, but check with your own health care professional before taking anything, including paracetamol.
Fainting - this is probably related to an increase in the size of the blood vessels (vasodilatation) due to the presence of the hormone progesterone. This then changes as the pregnancy progresses and the blood volume increases to fill the larger vessels. Try to avoid standing still in warm areas, and lie or sit down at the first sign of dizziness. This condition usually passes after the first trimester.
Muscle cramps - these are quite common later in pregnancy and are usually worse at night. The cause is unknown but can often be eased by stretching the muscle - sit up and pull the toes back towards the body over the ankles.
Itching - this can be related to a special condition or may just due to your skin stretching. Using antipruritic (itch) lotions, such as calamine can soothe itching. Alternatively your health care practitioner may be able to prescribe a cream.
Needing to urinate more frequently - this is one of the signs of early pregnancy and is probably caused by an increased amount of urine, and because your enlarging uterus puts pressure on the bladder. If you experience frequency during the night, you can try to alleviate the symptoms by reducing fluid intake after 4pm.
What about exercise during pregnancy?
If you exercise and are fit, you will be as ready as you can be for the physical nature of labour and birth. As a general rule, it is not advisable to start a new form of exercise during pregnancy. Ideally a woman should be regularly exercising before becoming pregnant. A regular, moderate exercise program can be continued throughout pregnancy, except when the exercise is very strenuous, such as at an athletic level. Regular exercise should not cause fatigue, and should be reduced if this occurs.
What and how much should I be eating?
It is essential to eat a nutritious diet during pregnancy. This will provide your growing baby with all the nutrients required for its development.
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