Your baby is increasing in weight more and more and is 16 inches from head to toe when you are 31 weeks pregnant. He has improved a lot in his features and can now move his head from side to side. You will be feeling these movements every time you react to some stimuli. Babies can kick up a storm even when they are not reacting to any stimuli, so expect that you will not be sleeping much as they baby will be kicking in your womb much of the time.
You will start experiencing some contractions as the muscles in your uterus tighten and loosen. These are what are referred to as Braxton Hicks contractions. Normally, they should be painless and irregular. They are just some of the signs that you are getting ready to go into labor and then into delivery. When they are regular and painful, it could be a symptom of preterm labor and not just Braxton Hicks contractions. When you feel this you have to call the doctor immediately as you may be giving birth.
You will notice an increase in vaginal discharge when you are 31 weeks pregnant. It will not have lost any consistency or color and when it does you need to call your doctor immediately as it could mean a lot of things. When it is itchy and causing a burning sensation it could mean that you are dealing with a yeast infection. With the latter, do not use over the counter medications unless you have the permission of your doctor. You will feel the need to pee all the time; much more than the time when you were in the early stages of pregnancy. This is normal since you have very little space to hold urine in your body. Your breasts will start producing some milk in preparation for the birth of the baby. This milk is what is called colostrum. You may need to get yourself some nursing bras. Purchase on size larger than your regular size of bra as your breasts will need a lot more space than normal.
You will have increased in weight a lot more than before and you will be feeling it. You will not be able to climb a flight of stairs as fast as usual and when you finally do you get tired too fast. You are not able to exercise as much as you did and you are suffering from more heartburn than you did before. Keep the changes in stride; do not worry much with these changes. Depression may kick in because of the fear of labor, being a parent etc. Again, take the changes that come with pregnancy in stride, do not worry whether you will become a good parent or not because many have passed through the same route. You need to perform activities that will reduce stress. If you have a hobby, now may be the time to start it all over again. Do not forget to eat well and take your supplements since your regular meals may not provide as many nutrients as you need.