Indian mothers believe that if you tie a saree very tightly around your waist after delivery, it helps you regain your pre pregnancy body. Is there any truth to this?

Yup, agree with Yuna that it sounds like binder and wraps. After delivery, binding helps so that the belly skin does not fall down. When it comes to weight lose, a combination of exercises and diet is recommended for the best results. If you are keeping to a healthy diet, engaging in regular activity, using a tummy binder may help you get back your pre-pregnancy body back sooner. For ladies who went through normal birth, it will take approximately six weeks for the uterus to shrink back to its normal size. An abdominal binder may help speed up this process. Binders could be worn the entire day or for however long it is comfortable for the mother. Typically, the binders are used for four to six weeks after pregnancy. You can start wearing an abdominal binder as soon as (or within) one week after birth. For ladies who went through C-section, it is advised to use the binder only after the surgery stitch is healed (usually at least six wee after delivery). Abdominal binders or tummy wraps could offer abdominal support for C-Section by compressing the abdominal tissues to reduce pain, shrink swelling and also help get your shape back sooner. In all, it is best to combine tummy wraps with good diet and exercise to help regain the pre-pregnancy figure.

I'm not too sure how accurate this is as none of my Indian mommy friends practice this nor do their parents. But I reckon it's a similar concept to tummy binders and wraps. Like the Malay have this "bendung" wrap that supposedly helps keep the tummy from sagging and to help flatten it. As long as the tightness doesn't hurt or gets too uncomfortable, i reckon there's no harm in trying if it were me. Anything to get my old figure back.