Well, I did it differently...
With my first, I was in regular clothes much longer, but my butt got wide and I had no choice but to buy maternity sooner than I wanted to. I spent a lot of time in overalls until summer hit, then I had no choice but to buy summer maternity things (including a bathing suit).
With #2 and more, I popped out right away and seriously was not comfortable in anything but maternity jeans (I loved the Under the belly varieties~ they fit for most of my pregnancies from the beginning right through post-partum) or big shirts and leggings (since it was the '80's when I had my oldest kids.

)
I could usually get away with regular tops for longer, but since I got huge with all the rest of my kids, I was in maternity sooner than anyone else in this thread apparently.
Using regular jeans but with a rubber band did Not work for me. I got wider through the hips & thighs so my regular jeans were so not comfortable at all.
I looked at my maternity clothes buying as an investment. I did not want to look like some beggar or like I was just too fat to fit in regular clothes. I needed to look nice (even when I felt crappy

). And, I just knew I'd be using them again, so I bought good quality stuff (on sale, mostly online with my last 3 pregnancies) that I could keep and use through several pregnancies. I also sewed a bunch of tops and dresses which saved me some cash.
I felt the same way about nursing clothes,(especially after #6 refused to have anything touching his face or to be covered with a blanket). I made a few essential pieces of nursingwear a priority to make it easier to nurse in public/church. Definately worth it for me.
