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Fast Facts on fetal development

  1. A human person’s life begins at fertilization when the father’s sperm penetrates the mother’s egg.
  2. From the time of fertilization, a baby’s unique DNA and genetic makeup are complete from sex to hair color to height as an adult. Fetal development is an amazing process.
  3. A baby’s heart begins to beat just three weeks after fertilization.
  4. Brain waves can be detected at six weeks after fertilization.
  5. At two months after fertilization, all of the baby’s organ systems are complete. The baby just needs to grow for the remainder of time in the womb.

Timeline of Fetal Development

Ever been curious about how your baby will develop?

Three weeks after conception, her heart began to beat.

Six weeks after conception, she had measurable brain waves.

By the end of the first trimester, arms, legs, fingers, and toes were all fully recognizable.

Twelve weeks she could make a fist with her tiny hand.

Nineteen weeks her ears were fully developed.

Twenty-three weeks after conception she had fingernails.

Twenty-five weeks Footprints and fingerprints were present.

Thirty-five weeks her muscles and bones were fully developed.

Learn More


3D ultrasound is a medical ultrasound technique used during pregnancy, providing three dimensional images of the unborn baby. Often these images are captured rapidly and animated to produce a 4D ultrasound. Below are 4D ultrasound videos from various stages of pregnancy: At 11-weeks; 22-weeks ; a 24-week and a 30-weeks (a yawning baby boy).

11 Weeks

22 Weeks

24 Weeks

30 Weeks

Free Ultrasounds

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