Your changing body and your growing baby

The second trimester

The baby

Weeks 13-16

  • The baby’s fingers and toes are well formed
  • Eyelids, eyebrows, eyelashes, nails and hair are formed
  • Teeth and bones become denser
  • The baby can suck its thumb, yawn, stretch and make faces
  • The nervous system is starting to work.
  • The reproductive organs and genitalia are fully developed.
  • You may be able to hear the baby’s heartbeat through an instrument called a Doppler when you visit your pregnancy care provider.
  • By the end of the fourth month, your baby is about 15cm long.

Weeks 17-20

  • Hair is beginning to grow on your baby’s head and a soft fine hair known as lanugo, covers the shoulders, back, and temples. This hair protects your baby and is usually shed at the end of the baby’s first week of life.
  • Your baby’s skin is covered with a whitish coating called vernix. This is thought to protect your baby’s skin from long exposure to the amniotic fluid and is shed just before birth although some of it visible on the baby’s skin after the birth.
  • Many women start to feel the baby move at this time.
  • Baby is developing muscles and using them. This first movement is known as quickening.
  • By the end of the fifth month, your baby is about 25 cm long.

Weeks 21-27

  • Your baby’s skin is reddish in colour, wrinkled, and the veins are visible through the baby’s translucent skin
  • Finger and toe prints are visible
  • The eyelids begin to part and the eyes open
  • Your baby may respond to sounds by moving or increasing the pulse, and you may notice jerking motions if baby hiccups

What’s happening to Mum?

The second trimester

  • In the forth month, your belly will grow with your baby and you will probably be ‘showing’, getting comments form friends, relatives, and strangers
  • If you had morning sickness this should be going during this time
  • Many women find that they feel really energetic
  • You may notice darkening of the area around the nipple (the areola)
  • Some women develop a dark line known as a linea nigra from the belly button to the pubic hair (if you can still see your pubic hair)
  • You may notice funny patches of darker skin which appear on the face and are made worse by being in the sun. These are known as chloasma and are perfectly harmless.
  • The uterus will be gently contracting from about 20 weeks. Most women don’t feel these so early on but some do. These are known as ‘ Braxton Hicks’ and should not be painful
  • By the end of the second trimester the top of the uterus is at the same level as your belly button.
  • This is the time that you start to gain a lot of weight and will start to look obviously pregnant
  • You may have what seems like a huge appetite as your metabolism and energy needs change
  • Most women find the second trimester to be the most enjoyable