What does your baby sense as they get ready to open their eyes?

Between weeks 24 and 28, your baby's senses develop quickly. Their eyelids, closed since the end of the first trimester, are getting ready to open, and sounds, touch and light are becoming part of their little world.

When do the eyes open?

Your baby's eyelids close toward the end of the first trimester and stay closed for weeks. In the sixth month they begin to part, and the eyes usually open for the first time between weeks 26 and 28. After that, your baby learns to open and close their eyes and to blink. By around week 26 all parts of the eye have developed, and eyebrows and eyelashes become more defined during these weeks.

There is no rush to find out eye color: the idea that all babies are born with blue eyes is a myth. Eye color depends on the genes passed down in your family and can keep changing for a while after birth.

How does your baby sense light and sound?

Even with closed eyelids, babies are reported to react to bright light. Toward the seventh month, they start to respond more clearly to stimuli such as sound and light. Behind these responses is a fast-developing brain: after week 27, brain growth speeds up and the nervous system matures enough to control some body functions.

Hearing starts earlier. In studies, the first responses to sound are seen around week 19. By week 27 almost all babies respond to low-pitched sounds, while responses to high-pitched sounds settle in around weeks 33 to 35. They can hear sounds from inside you, such as your heartbeat, your breathing and your stomach rumbling. A loud noise can startle them, which may be why you suddenly feel a kick.

Does your baby recognize your voice?

The research showing that babies can tell their mother's voice apart from others was done close to birth. So we can't say for sure that your baby “recognizes” your voice at this stage, but their hearing improves a little more every week. Things you can do in these weeks:

• Talk, sing or read aloud to your baby; your partner and family can join in too.
• Avoid spending long periods in very loud places. Researchers point out that intense noise may affect the developing hearing system at a time when babies are especially sensitive to low-pitched sounds.

“Talking, singing or reading to your baby can be a lovely habit for both of you.”

Keep track of movements

Your baby is developing their own pattern of movements; try to get to know it. After 28 weeks, 10 movements in 2 hours is considered normal. If you notice your baby moving less or a change in their usual pattern of movements, go to labor and delivery right away — don't wait to count kicks or reach 10 movements.