24 Weeks of Pregnancy: What’s Happening? At 24 weeks, let’s take a look at the exciting developments inside the uterus! Baby’s Growth • Size: About 30 cm and 600 grams, roughly the size of a corn cob. • Development: • Rapid growth in fat, muscles, organs, and bones. • Hair, eyebrows, and eyelashes are now visible but white due to the lack of melanin pigment. The color will develop later. • Hearing is fully developed—your baby can now hear external sounds! Father’s Role Fathers should start bondi