As you enter the second trimester of pregnancy, or the 4th month, your baby now has fully formed fingers and toes, as well as eyelashes, brows, and eyelids. His/her hair is formed, and bones density increases. You might even notice your baby sucking their thumb, yawning, or make faces during your ultrasound. Your doctor can finally tell you the sex of your little one, and let you hear the heartbeat.
In addition to hearing your babys heart beating, and finding out the sex, you will also start to feel it move. You will also probably need to loosen your waistband, as your clothes may not fit any longer. Your baby bump will be more pronounced, as well as your need to pee. Trips to the bathroom to urinate will become more frequent, as your baby starts to push on your bladder. During the second trimester, you will no longer experience nausea.
However, you will experience heartburn, constipation, gas, and an increased appetite. Your nails and hair may become thicker, dryer, or oilier. You may also begin to notice stretch marks, and experience swelling in your ankles, along with a tired achy back and feet. Your fatigue may increase, as your body deals with the added weight and hormonal changes.