First Trimester

Pregnancy Month By Month

First Trimester To-Dos

  • Take your prenatal vitamin
  • Schedule your first prenatal appointment
  • Choose where you want to deliver
  • Start thinking about your birthplan
  • Visit your company’s HR Department to get details on maternity leave
  • Make a budget
  • Eat right
  • 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


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 you 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 bra and maternity clothes.

Side view of young cheerful pregnant model standing at window with beautiful city scenery and drinking hot beverage. Future mom relaxing at home with tea or coffee. Copyspace


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 25 day.

Length: 1/2 inch

Weight: Less than 1 oz.

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