Probiotics help alot too.
I was taking them daily until about 18 weeks
Per my OB you can Dolace or its generic as a softner.
Eat activia twice a day for the remainder of your pregnancy
I used benifiber 2 times a week and it helped a lot. Other than that drink lots of water and keep moving
Your ob can prescribe something. Never rake any thing with out asking your ob
Try some orange juice that always works for me :)
First of all, bananas are really bad for constipation. Actually you should avoid them all along.
So, constipation happens when there isn't enough water in your stool, it gets hard and it's difficult for your intestine to move it out your body. So first I would focus on my water intake. Are you drinking enough water?
Second step, fiber. Fruit this time of the year is great, so many different kinds you hardly get bored of fruit. Remember that, in order to actually get all their fiber you must eat it with its skin. This means that not all fruit has a good fiber count: if you have to peel it, then it's no good! Fruits you should be eating: apples, peaches, plums, pears, berries... The only exception I can think of is kiwi and pineapple, which work great with constipation.
Last but not least.. Exercise!
PS, my doctor said I could have certain laxative, I never used it so I can't tell you the name. It was pregnancy-safe. Stool softeners are not recommended during pregnancy. If the advice is not working for you, I'd ask my obgyn about the medication.
Good luck!