Gosh, I was proud as punch over my preggy belly and wore bikinis - didn't think twice! I was so chuffed my normal bikini fit while pregnant

TBH, they wore a lot more clothing in general when your mum was our age. And bikinis would have been quite risqué, let alone when pregnant! My mum made a few comments about my clothes while I was PG which could have been perceived in a negative way but that wasn't her intention at all. My mum was merely pointing out the major differences between when she was PG. She mostly said they were encouraged to (had to?) wear loose fitting, big clothes while our generation wear fitted clothes to show off our bumps

Anyway, what your mum said is pretty wrong. Don't be ashamed, pregnancy is a beautiful thing