The Wonders of Fetal Development

By briannag09252

  • Week 1

    Today is the first day of the last menstrual period.
  • Period: to

    First Trimester

  • Week 2

    The uterus begins forming a lining called the endometrium that will thicken over time as eggs mature and form each week prior to ovulation.

  • Week 3

    Ovulation occurs and the egg in the uterus becomes fertilized.

  • Week 4

    The sex of the baby is determined by the number of chromosomes after the division of the egg.

  • Week 5

    The placenta, also referred to throughout pregnancy as the baby's "life support" is developed.

  • Week 6

    The lobes in the baby's brain begin to develop by dividing into five parts.

  • Week 7

  • Week 8

  • Week 9

  • Week 10

  • Week 11

  • Week 12

  • Week 13

  • Week 14

  • Period: to

    Second Trimester

  • Week 15

  • Week 16

  • Week 17

  • Week 18

  • Week 19

  • Week 20

  • Week 21

  • Week 22

  • Week 24

  • Week 25

  • Week 26

  • Week 27

  • Period: to

    Third Trimester

  • Week 28

  • Week 29

  • Week 30

  • Week 31

  • Week 32

  • Week 33

  • Week 34

  • Week 35

  • Week 36

  • Week 37

  • Week 38

    The baby weighs around seven and a half pounds.

  • Week 39

    While in its final birthing position, the baby will continue to kick under pelvis that can cause discomfort to the abdomen.

  • Week 40

    Contractions begin to indicate the arrival of the due date.