In my experience cycling has been the best thing for pregnancy and birth. With Molly I cycled right up until a few hours before she was born and I did the same with the new little Daisy that has appeared on the scene (my tip for getting labour off to a flying start is to ride down a potholed road before tackling a 1:4 hill).
With both pregnancies I didn’t do one antenatal class – I thought rather than sit in a room trying to learn how to puff and pant I’d rather go for a bike ride (a more enjoyable form of puffing and panting. With cycling, you often push yourself beyond what you think you can do which means riding through several pain barriers and you do similar things when giving birth. Because of my age (I’m an old bird) I was statistically high risk and doctors and midwives were a bit concerned until they took my blood pressure and heard that I’d arrived at the hospital by bike. Luckily my lump of a bump was of a size that some of my neighbours didn’t know I was pregnant – I think I had a sort of packable, foldable travel version that could fit in a pannier. Saying all this, cycling wasn’t quite the breeze I was used to – my lungs felt in my throat and my stomach felt in my lungs. But still I could cycle and pull my trailer full of a ten-ton Molly – and for me that was the main thing. Have bump will travel, and preferably by bike.