The first trimester of pregnancy is a critical time for your child's development. Knowing what to expect and what is happening inside your body will reduce stress and prepare you for a happy, healthy pregnancy.
What To Expect
During the first few weeks of pregnancy, hormones trigger changes in your body. Your breasts may feel sensitive, full and heavy. Some spotting, or implantation bleeding, may occur. Usually this bleeding is very light and only lasts a day or so.
A common symptom of the first trimester of pregnancy is nausea. It may be helpful to eat frequent, small meals throughout the day to avoid queasiness and vomiting. If your nausea is severe, you feel faint and can't keep liquids down, consult your doctor.
Heartburn, constipation, over-active bladder, dizziness and fatigue are all commonly experienced during the first trimester. Your body is working hard to grow your baby and affects other functions, such as digestion and energy.
Pregnancy is an exciting, stressful and beautiful time. When combined with all of the hormonal changes occurring in your body, it is a very emotional time. Keep in mind that your body is going through a lot of changes and emotional sensitivity is healthy and normal. However, if you feel overwhelmed, don't hesitate to ask for help.
The first trimester begins at conception. During the first few weeks of pregnancy, the neural tube forms, which eventually develops into the nervous system, including your baby's brain and spinal cord. The baby's life support system, including the heart and circulatory system, is also forming during the first 4 weeks of pregnancy.
During the 5th and 6th weeks of pregnancy, your child's first heartbeats begin, blood pumps and the umbilical cord forms. At this stage, arms, legs and your baby's organs start to grow. Your baby will start to resemble a newborn during this stage as it's nostrils and eye lenses begin to develop. By the end of the 6th week, the pancreas has developed and the intestines are growing outside of the body, in the umbilical cord.
Elbows, fingers, feet and toes develop during week 7. Ears can now been seen and teeth begin to grow under your child's gums. Cartilage and bone start to develop along with your baby's tongue. The intestines move from the umbilical cord into the baby's body. By the end of week 8, the baby has grown to about 0.6 inches in length.
By week 9, most of the joints are fully formed and the baby is now able to move around, though you won't be able to feel it yet. The baby is officially a fetus at week 10 and the most critical stage of development is complete. The fetus will start to grow rapidly from this point on. The eyelids fuse shut so the irises can start to develop.
During the 11th and 12th week, hair and nails begin to grow and the fingers and toes have separated. Your baby's genitals begin to develop but it will take a few more weeks until an ultrasound can determine gender. Kidneys start to function and amniotic fluid builds up, cushioning the fetus in the womb. The pancreas starts to produce insulin and the liver is now functional. By the end of week 12, your baby has grown to about 2.13 inches.
Week 13 and 14 are the final weeks of the first trimester. The thyroid gland has matured and the fetus begins to produce hormones. By the end of the first trimester, your baby will have grown to about 3.4 inches.