The phrase
"tightening sensation" refers to the feeling of something becoming tighter or constricting. It could be a physical sensation, like muscles getting tense, or a metaphorical sensation, like feeling anxious or stressed.
Full definition
It's only as the uterus grows bigger that you notice
the tightening sensations.
Just remember, if
the tightening sensations go away on their own, the likelihood is that they are just Braxton Hicks.
If you have
tightening sensations 4 or more times in an hour and are more than 3 weeks from your due date, call your doctor immediately.
They feel like
a tightening sensation that begins at the top of your uterus and then spreads downward, lasting from 15 to 30 seconds (though they can sometimes last two minutes or more).
You should feel
a tightening sensation, and when you rinse off, your eyes may look much better.
Interestingly, it does give
a tightening sensation as the day progresses, more like «oil being sucked»; with that said, I don't think this will work if you have dry skin.