Here is a super simple way of creating an egg shape oval using the Circle / Ellipse tool, and a little known feature of the Node Tool, called Node Sculpting.
Draw a circle
First up, use the circle / ellipse tool to draw a circle. Remember to hold down the control key on your keyboard to make sure it is a perfect circle.
Convert the circle to a path
Use the select tool to select your circle, and convert it to a path with Path > Object to Path. Now when you switch to the node tool, you will see your 4 nodes of your path.
Sculpt the Nodes
Using the Node Tool, select all the nodes in your circle path either by dragging a box around them, or using the keyboard shortcut Control + A. Now press the alt key on your keyboard, and click and drag the top node of the shape. Your simple egg shape is now complete!
Check out Tav’s book for more information on Node Sculpting