The Second Trimester: Your Baby's Growth and Development in Middle Pregnancy

Your baby grows and changes fast during your second trimester. Here's an inside peek at her amazing progress! By week 13, she's as large as a lemon -- about 3 inches long. And she's learning how to swallow by taking an occasional gulp of the amniotic fluid around her. Next week, she's a little bigger -- the length of a bell pepper. But by week 15, your baby could be the size of a large russet potato -- around 6 inches long. Her bones get harder and stronger during week 16. Now she can flex her arms and legs. Plus, her eyes can slowly move around behind closed lids. Next week she's the size of an asparagus spear -- almost 8 inches long. And she's on the move, doing flips and rolls. She can also make a fist and hold it to her mouth. Her face gets more defined during week 18. Those little eyelids, ears, and upper lip all come into sharper focus. Plus, she can hear sounds now. Your little one maybe over nine inches long -- about the size of an eggplant -- by week 19. Her lungs' main airways start to form. Something super adorable happens in week 20 -- your baby puts her feet and toes in her mouth. She also gets lots of sleep. Noise and movement can wake her up -- so keep it down, would ya? (Just kidding.) Next week your 10 and 1/2-inch tot is making strong kicks and turns. She's also forming brown fat for warmth. Your baby's genitals are completely formed around week 22. It's possible to see her eyebrows now, too. And soft, warm hair called lanugo covers her. By week 23, her fingers and toes look like tiny versions of yours -- and they've got fingerprints. Plus, your little one now has a secret talent: she can hiccup. At week 24 your baby is pineapple-sized -- about 12 1/2 inches long-- and 1 1/2 pounds. She could survive outside your womb if she was born now. Your little one knows the sound of your voice at week 25. She can recognize other familiar sounds too ... when she's not sleeping. She snoozes 80% of the time now. By next week, she knows how to suck -- and she'll probably try that skill out on her thumb. At the end of your second trimester on week 27, your little one is the length of an English cucumber -- over 14 inches long. And all that moving around is paying off, giving her more and more muscle tone.