No, it wont cause your cervix to open, very few external factors would cause this x
But it may cause a UTI as it could stop you emptying your bladder properly x
I've been so, so constipated this baby. I have taken senna, which worked OK, not brilliantly because I couldn't drink lactulose. Everyone's different just try what works for you.
Have you tried putting your feet on something raised when sitting on the toilet or actually squatting over the bowl?
The raised feet, increased intra-abdominal pressure and helps to force the poop out, and the squat relaxes and straightens the colon completely so should aid in getting out a trick poop.
Try both positions, it could be as simple as that xxx