An amazing part of skeletal development is the growth and change of the hands. As the brain and nervous system develop, the hands are able to move, clench fists, and grasp.
Your hand and arm started to develop very early in your life! In your fourth week, your arm bud development began, and hands started out as flat paddles by the end of your fifth week.
Fingers began to form but were still webbed. In Week 7, your elbows became more defined. Your fingers were fully separated by the end of week 8.
10 weeks after conception, your fingernails started to grow. By Week 34, they had reached your fingertips.
By Week 14, you began to suck your thumb. You could open and clench your fist, and used to move your hands quite a lot! By week 38, your grasp was quite firm.