I feel them all the time. I'd say I probably have 4 or 5 per hour, every hour... I feel them during the day and night, so activity level doesn't seem to be much of a factor. They are much worse after sex, but orgasm is contraction of the uterus, so that makes perfect sense. The BHs I have regularly as quite noticeable, but not painful. As the pregnancy progresses, though, they will become more frequent and more intense. I've had them so much with each pregnancy--during my first pregnancy they really freaked me out and I ended up spending the night in the hospital around 25 weeks to be monitored... I was diagnosed with an "irritable uterus" and told to limit my time on my feet (I was working in a nursing home at the time). Since then, I've carried 4 more babies till at least 35 weeks and my "irritable uterus" has never been an issue--nor have I found staying off my feet to reduce the BH ctx.
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