The nesting instinct is the name given to a pregnant woman's sudden, energetic urge to prepare for her newborn baby.
It is often believed to be a sign that labour is imminent. However, this has no scientific basis and the nesting instinct should be considered a quirk of pregnancy rather than a definitive sign of birth.
A woman who is nesting will have a desire to clean her property - often from top to bottom - and wash all blankets, clothes, toys and bedding in order to prepare a clean and healthy environment for her newborn.
Other signs of the nesting instinct include a desire to tie up any outstanding issues such as home or financial projects and an impulse to purchase and organise everything a newborn baby will need.
The nesting instinct can happen at any time during a woman's pregnancy, sometimes as early as five months, but most pregnant woman who have experienced the instinct will say that is happens towards the very end of the pregnancy.
However, it is always recognisable as a sudden burst of energy. This sudden burst of energy is particularly noticeable in a heavily pregnant woman as she will typically be experiencing tiredness and lethargy in very late pregnancy. However, some women may never experience the nesting instinct, while others may find urge impossible to resist.