At 18 weeks your baby is about 14.2cm long - the size of a sweet red pepper - and weighs around 190g1.
Around weeks 18-20, you may also start to feel your baby’s first movements as they switch between sleep and active wakefulness. These first movements are usually little kicks and rolls that feel light and fluttery2. If it’s your first pregnancy you may not notice them or even mistake them for mild indigestion as many mums-to-be report feeling more movement after a meal or late at night2.
Around this time, your baby may also start responding to noises from the outside world, making this an ideal time to start talking to your bump3. Your baby’s reflexes are also continuing to develop - swallowing, sucking and hearing4.
Inside your baby’s lungs, air sacs called alveoli are starting to develop and it’s common for your baby to experience hiccups at this stage3, although it’s unlikely you’ll feel them.