By the end of this week, your baby is 5 inches long and weighs approximately 2 ounces.
Your baby’s skin is very thin, it’s almost transparent and the veins carrying blood around its body can be seen through it. A fine covering of downy hair called lanugo is beginning to grow all over the body. This soft hair is usually lost just before or after birth, although premature babies often have more when they are born. Your baby’s ears are continuing to develop externally and continue to look more like normal ears. Your baby’s eyes are moving towards the nose from the sides of his head. His bones are beginning to ossify, which means that if an x-ray were taken the skeleton would be visible.

Between 15 and 19 weeks your midwife will offer you a blood test to look for a substance called maternal serum alphafetoprotein. If it is present, it is a sign that your baby may have spina bifida. Spina bifida is a defect in the neural tube of your baby, which develops into the brain and spinal cord. If you have taken folic acid supplements before conception and in early pregnancy, you will have reduced the risk of having a baby with this condition.

Some women experience anemia during pregnancy, either because there is not enough iron in their diet or they need more than usual due to the demands of pregnancy. Iron helps to carry oxygen in the blood of the mother and baby. Eat lots of green, leafy vegetables, leans meat and dried fruits. Your GP may prescribe iron supplements, which are best taken with orange juice.

Changes in the shape of your abdomen may now be noticeable to others. You may be able to feel the top of your uterus four to five inches under your belly button.

Begin sleeping on your side now, as this is the most comfortable and healthy sleeping position. Sleeping on your back can causes your uterus to place pressure on the aorta and inferior vena cava, which supplies blood to your lower body and your baby. Sleeping on your stomach also places extra pressure on your uterus and should be avoided. Many women find placing pillows behind their backs and between their knees very comfortable.