Your Baby at 13 Weeks Pregnant
The producers. Now that your fetus has completed the task of forming all the critical body structures, the organs go to work. The liver secretes bile, the pancreas produces insulin, and the kidneys form urine to carry waste away. The urine is excreted into the amniotic fluid. Your little one's intestines, which have partially resided in the umbilical cord, have moved back into the abdomen now that there's enough room to accommodate them.
Head case. Your little one is now about the size of a large plum, weighing less than an ounce and measuring anywhere from 2.6 to 4 inches. The head takes up half of that length, thanks to all that brain development. Over the next few months, the body will grow at breakneck speed to catch up. When your baby is born, the head will be only a quarter of the total length.
Your Pregnancy at 13 Weeks
Welcome to the second trimester! Many women describe the next few months as the honeymoon period of pregnancy. The discomforts of the first trimester — fatigue, nausea, frequent urination — ease up a bit and you finally start enjoying being pregnant. Many women even feel a surge of energy during this trimester.
One reason why you may feel pregnant is that your waistline is starting to thicken. Your regular pants are probably getting a little snug, and you might feel more comfortable in those cute maternity outfits you've had your eye on. Whatever you decide, dress with comfort in mind.