As needles and thread should I use for maternity jeans?

I'm cutting out the old jeans and turning them into maternity jeans attaching stretch fabric top. What thread and needle size / type should I use the jeans alone and also when sewing stretch fabric of the jeans?

You will need to use needles or 100/16 jeans you miss sewing. When sewing two different types of fabric, choose the type needle for the heavier of the two tissues. Coats & Clark Dual Duty or any other brand of polyester thread works fine. Do not use cheap fillets sold for $ 1.00 per roll.

Hand Sewing Stitches : Types of Needles for Hand Sewing