Great list of the best core exercises you can do for women.

Cables Back Extension

Stand on platform and hold cable handles to your sides. Keep your head up, back straight and your knees slightly bent. Bend at the waist and lean forward until your upper body is parallel to the ground. Pause briefly then return to the starting position. Do not allow muscles to relax before next repetition.

Seated Leg Tucks

Sit sideways on a bench and grasp the edges of the bench for support. With bent knees, raise your legs slightly and then straighten them. Lean backward as balance requires. Next, lift your knees up towards your chest while keeping your lower legs pointed downward and flexing (tightening) your abs as hard as you can. Keep continuous tension on the abs throughout this movement. This works both upper and lower abdominal muscles.

Ball Waistline Trimmer

Primary Muscle Group: Internal and External Obliques

Muscle groups worked in this exercise:

Preparation: Lie on the floor on your back with knees bent and place both heels on the ball. Now, interlace your fingers behind your head and make sure your elbows are out to the sides.

Medicine Ball Lying Oblique Twist

Lie face up on floor, knees bent with feet on floor and neck straight. Grasp medicine ball and hold at chest level. In a controlled motion, keeping neck straight, curl upper body up. From this position, twist your torso to the left. Contract abdominals fully without compromising form. While maintaining the controlled motion, return to starting position and continue through to your right side. Focus on really twisting your torso and feeling the contraction when twisiting your torso.

Ball Side Lifts

Lie face down with ball under your hips. Bend your left knee and lift up towards your chest. Finish by extending and driving your left leg behind you. Return to the starting position and repeat.