Keeping teeth clean is important to ensure the health of your teeth and gums. Plaque and trapped food can lead to tooth decay and the gum disease called gingivitis.

The blood-brain barrier is a semi-permeable lining that prevents most substances from passing into the brain, according to Washington University.

During the last trimester of pregnancy, mothers give their babies enough iron to sustain them for the first four months of life. Most babies get adequate amounts of this nutrient from iron-rich foods or iron-fortified formula after four months.

Eczema can be a sign of allergies in a baby. Proteins in foods can pass into the mother’s breast milk and cause allergic reactions in some babies. The La Leche League organization says that babies often grow out of these allergies within the first few years and the eczema disappears.

Keeping your baby cool during the summer months is important to reduce the risk of your child overheating. According to the American SIDS Institute, overheating can increase the risk of sudden infant death syndrome. Air conditioners help regulate the temperature indoors and in cars on hot and humid days.

Infants cannot tell you if they are feeling hungry or are full. As a parent, it is your responsibility to ensure that your child is getting the proper amount of calories per day. In general, you should feed your young infant when he is hungry, which is known as feeding on demand, notes the KidsHealth website.

Gagging is a normal reflex in babies and can happen for several reasons. Everyone has a gag reflex to help prevent choking. When a baby, who is up to about six months old, feels anything on the back of his throat, he will push his tongue forward.

Your baby's development as an embryo begins with fertilization of the egg by a sperm, followed by rapid cell division. Initial division results in the formation of a ball of cells that then folds, divides, changes and grows into your baby with a genetically determined set of characteristics and appearance.

Making the transition to eating solid foods is an important milestone for both baby and his parents. A baby’s digestive system must adjust to the new foods and can cause baby to be cranky and feel uncomfortable. Babies can be introduced to solid foods between four to six months old.

Tooth loss is unpleasant to face, but well-fitted partial or full dentures can be indistinguishable from your natural teeth. Dentures are available in several types of materials, including porcelain, acrylic resin and composite resins, with porcelain and acrylic resin being the most common.

From the moment your baby is born and for the first few months afterward, she'll likely spend much of her time with her hands folded. Her hands won't always be folded together, but rather in a slight fist. Though if you've ever let a baby hold your finger you know what a tight grip it can be.

Learn the signs of not being able to have a baby, including common symptoms and factors that can affect fertility. Understand why some couples struggle with getting pregnant and find natural ways to improve your chances.