Maternity - First trimester
The first trimester lasts from week 1 through the end of week 13. During this time, your body will undergo extraordinary changes in a relatively short amount of time.
First-trimester checklist
- Take your prenatal vitamin
- Schedule your first prenatal appointment
- Start thinking about your birth plan
- Check insurance and benefits coverage
- Eat a healthy diet
- Make time to exercise
- Research childbirth class options
Typical pregnancy symptoms
- Morning sickness
- Tender breasts
- Mood swings
- Heartburn
- Constipation
- Metallic taste
- Food aversions
- Headaches
Reasons to call your doctor
- Heavy vaginal bleeding
- Severe abdominal pain
- Sudden thirst
- Painful urination
- Fever over 101.5, chills and/or backache
- Severe puffiness in hands/face
- Vision disturbances
What’s happening with mom
Month 1: You have missed your period, or it may have been very light. You may not notice any other differences yet, but the hormones progesterone and estrogen are being produced in increasing quantities. Your breasts are slightly enlarged and tender, and your nipples have become more prominent. You probably urinate more.
Month 2: The total volume of blood in our body increases to accommodate the growing fetus. Your breasts are still tender. You may be experiencing some discomfort as your body adjusts.
Month 3: Your waistline will begin to disappear as you gain weight. You may need to purchase a larger size bra and maternity clothes.
What’s happening with baby
Month 1: By the end of the first month, the embryo has a head and a trunk. Features are beginning to form as well as limb buds that will grow into arms and legs. The heart forms and begins beating on the 25th day.
Length: 1/2 inch
Weight: Less than 1 ounce
Your baby is the size of an apple seed
Month 2: All major body organs and systems are formed, although not completely developed. The heartbeat can be detected, and the first bone cells have appeared. Ears, ankles, wrists, fingers and toes are developed.
Length: 1 inch
Weight: Less than 1 ounce
Your baby is the size of a kidney bean
Month 3: Hair is beginning to form on the fetus’ head. Kidneys develop and produce urine. Organs will continue to mature, and the fetus will gain weight.
Length: 4 inches
Weight: Over 1 ounce
Your baby is the size of a lime or a baseball