At 23 weeks your baby is a little more than 11 inches from head to toe, and weighs over a pound(about the size of a large mango or a grapefruit).
Blood vessels in your baby’s lungs are developing to prepare for breathing. Now that the bones in your baby's ears have hardened, it can make out a distorted version of your voice, the beating of your heart, and stomach rumblings. And the sounds that your baby's increasingly keen ears pick up are preparing for entry into the outside world. Loud noises that become familiar now – such as your dog barking or the roar of the vacuum cleaner – probably won't faze baby when it hears them outside the womb. The lungs are developing to prepare for breathing. Baby's skin is a bit saggy (but won't be for long as fat begins forming) and has a red hue thanks to the developing veins and arteries right underneath. Although your baby's organs and bones are visible through the skin, it'll become less transparent once those fat deposits settle in. By the time your baby is born, it will be pleasantly plump and filled out, from chubby cheeks to chubby toes. Billions of brain cells will develop in your baby's brain over the next couple of weeks. These will control all of your baby's movements and sensory, and basic life functions like breathing. Also around this time, some major changes are happening with your baby's lungs. Surfactant is being produced, a substance that enables the air sacs to inflate and the lungs to fully expand. Right now it's still breathing amniotic fluid, but when baby's born it'll be ready for air. Those little arms and legs are packing more of a punch these days...you might even see them poke through from the outside! If you pay attention, you’ll get to know your babies routine: baby’s less active when he or she is sleeping and a kung fu master when he or she’s awake. Some parents even swear their newborns kept similar routines after birth as they did in utero. Often babies are born with their night and day backwards, as they tend to sleep when mom is busy which then rocks the baby. Just when you want to lie down to rest or sleep baby will think it is party time!! The placenta — baby’s recently completed life-support system — transfers oxygen and nutrients to baby and removes waste products.
Note: Every baby develops a little differently — even in the womb. This information is to give you a general idea of your baby's size.
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