This problem is one that many mothers deal with. Because of the large temperature difference between day and night, mothers always are afraid their babies have a cold during sleep. So they usually choose a big baby quilt size. Then they will find newborns sweating at night sometimes. 

1. Why babies will kick the quilt?

1.1 feel hot

1) faster metabolism
  Compared to adults, babies' metabolisms are faster. Their bodies’ temperatures will also rise. So babies are easier feel hot during sleep. When they are hot, they want to kick the quilt. 
2) wear too much clothing
  Every mother doesn't want her baby to catch a cold. So mothers always wear as many clothes for their babies before going to bed. Wearing too much clothing makes babies feel hot.  

1.2 overexcited before bedtime

  Before going to sleep, parents should not play with their babies to make them excited. They are prone to move their hands, their feet around at night, and then kick the covers off.

1.3 wrong sleeping position

  Some babies will burrow their heads inside the covers, or sleep face down. These will also make them kick off the covers. Because they will feel too hot or may kick the quilt while rolling over. Parents should promptly help the baby sleep on their backs, or sleep on their sides, both of which are more comfortable and safe. 

2. What to do when the baby kicks the quilt?

2.1 don't use a thick quilt

  Some mothers are worried about their babies kicking the quilt and getting cold. So they specially prepare a thick and heavy quilt to help the baby avoid kicking. However, thick and heavy quilts tend to cause the baby to swelter, sweat, and may make them repeatedly wake up at night, babies are unable to get a good night's sleep. Poor sleep has a big impact on your baby's growth. So pay attention to not doing it.

2.2 choose a suitable sleep sack

  Sleeping bags can give your baby a safe and comfortable sleeping experience.
  When you are choosing a sleeping bag for your baby, pay attention to the following points. 
1) Choose a sleeping bag of pure cotton fabric.
  The inner layer of a sleep sack against the baby's skin. It is better to choose natural, healthy fabrics. Such as bamboo fiber, 100% cotton, organic cotton, etc. These fabrics are all soft and sweat-absorbent that will not stimulate the baby's sensitive skin.
2) The internal space of the sleeping bag should be loose.
  A good sleep sack can not prevent the baby from turning over obstructed. It is easy to wake babies up at night and affects the quality of sleep. The sleep sacks need to be flexible, loose. On one hand, babies can feel more comfortable. On the other hand, babies can roll over and move freer.
3) Sleeping bag closure is best to choose the zipper.
  Because the closure with buttons and buttons will have gaps, the baby's hands and feet will reach out unconsciously, and may be stuck in the gap. 
4) The thickness of the sleeping bag can also make a difference.
  Different seasons need sleep sacks in different thicknesses. Babies can wear breathable, thin layers of sleep sacks in summer, and wear thick, warm sleep sacks in winter. 

2.3 adjust the room temperature

  The temperature of your baby's room is best kept at 22 to 24 degrees Celsius. The indoor temperature varies across the countries and in different seasons. As long as the skin on the back of the baby's neck is dry and warm. It means that the temperature is appropriate, and your baby is not cold and not hot. Sometimes, mothers find that the baby's little hands are cold, they think babies must be cold. But in fact, this is potentially inaccurate.