I'm the tiniest girl you can imagine.. size 0, barely even 100 lbs. I was 95 lbs at the start of my first and only pregnancy and I gained only 13 lbs, and the baby was born 6 lbs and 6.8 oz, 19.5 inches long! It's amazing the capacities of what our bodies can accomplish and do! I'm very underweight now though with a low BMI for my height, and it's just been lots of stress dealing with my baby daddy and his family, and in general just all the consumption of my energy taking care of my 3 yr old with not too much help from anyone else. And man.... little boys have soo much energy! I swear I thought boys would be easier than girls, but the only thing easy about them is that they're simple to get ready to get them out the door... you just throw a t-shirt on and some shorts and comb their hair. But boys are not content to be homebodies, they go stir-crazy at home if you don't have a big yard to play in or a pool, or something! They need to be in sports and taken to the park all the time or on outing... they like to be out and about always! They are not content to be at home reading or drawing, playing with dolls, and helping mom cook. And one other thing is... Dang can boys put it down and eat a lot! I swear I am having to go to the grocery store like every few days because this boy of mine wants to eat so soo much! Girls are definitely not like that! I already got rid of my Audi because it was driving a hole in my pocket maintaining it and spending on gas/oil, and parts... etc. I have a Nissan Versa sedan now which was my sacrifice in being able to continue to afford this boy of mine's appetite! lol Anyways, about "pregnancy bumps"... I already felt my uterus hardening into a ball and tightening and contracting with braxton hicks as early as 9/10 weeks. The doctor had said it was normal to start occurring this early and it was the uterus form of "practicing" for labor/birth already. I could already see the difference and my 'bump' when I was 9-12 weeks. I looked bloated. By 5 months, it looked like I'd eaten a big lunch and a beer to go along with it, and hadn't digested it, but no one else could tell I was pregnant. At 6/7 months I really started to pop, but I still think I could have hid the pregnancy up until 5 months. It's harder for skinny petite girls to hide things from showing though for sure.