fiber

Hi, yes, I am 47 and have had 4 pregnancies. I feel as though my vagina muscles and rectum area have sunk south so to speak! Would this be prolapse? What is prolapse? What causes the sensation of straining even though the stool is soft for a lot of us women? Is it from having several pregnancies? I have noticed this for the last few years. When I relax at night, everything in the rectum area feels okay, relaxed. I go to bed and when I get up, I feel okay, have my 2 or 3 bms and then notice that there appears to feel like a weight or something pressing down on the vagina and rectum area. It goes away when I get off my feet. The more I stand, the worse it gets. I don't notice it so much if I am out and about town, but in my own home, I am soooo focused on it, it bothers me.
I'm really pleased with the stools I have been getting and I drink 5 glasses of water in the morning to lunch and then a couple of lunch, but tend to slow down in the afternoon. How much should I be drinking? It is costing me so much to buy my bottled water. I drink 2 hot mugs of water in the morning, plus a glass of juice, a glass of water and a bottle of water at work by lunch. Then in the afternoon, I walk the dog, drink another bottle of water and a glass of water after that. I feel consumed by all this water? How much is enough? I feel I really need to relax about all this bowel stuff. you guys really help.