Nesting instinct refers to an instinct or urge in pregnant

Pregnancy

Pregnancy refers to the fertilization and development of one or more offspring, known as a fetus or embryo, in a woman's uterus. In a pregnancy, there can be multiple gestations, as in the case of twins or triplets...

 animals to prepare a home for the upcoming newborn(s). It is found in a variety of animals (both mammals and birds) including humans.

In animals

In rodent

Rodent

Rodentia is an order of mammals also known as rodents, characterised by two continuously growing incisors in the upper and lower jaws which must be kept short by gnawing....

s and lagomorphs, the nesting instinct is typically characterized by the urge to seek the lowest sheltered spot available; this is where these mammals give birth. Female dog

Dog

The domestic dog is a domesticated form of the gray wolf, a member of the Canidae family of the order Carnivora. The term is used for both feral and pet varieties. The dog may have been the first animal to be domesticated, and has been the most widely kept working, hunting, and companion animal in...

s may show signs of nesting behavior shortly before their due date that include pacing and building a nest with items from around the house such as blankets, clothing

Clothing

Clothing refers to any covering for the human body that is worn. The wearing of clothing is exclusively a human characteristic and is a feature of nearly all human societies...

, and stuffed animals. (They also sometimes do this in cases of false pregnancy

False pregnancy

False pregnancy or hysterical pregnancy, most commonly termed pseudocyesis in humans and pseudopregnancy in other mammals, is the appearance of clinical and/or subclinical signs and symptoms associated with pregnancy when the person or animal is not pregnant. Clinically, false pregnancy is most...

, or pseudocyesis). Domestic

Domestic

Domestic or domestique can refer to:* A cycling domestique* A domestic worker* Domestic airport* Domestic violence* Domestic , a group with Trust in Trance Records* Domestikos , a Byzantine title...

 cat

Cat

The cat , also known as the domestic cat or housecat to distinguish it from other felids and felines, is a small, usually furry, domesticated, carnivorous mammal that is valued by humans for its companionship and for its ability to hunt vermin and household pests...

s often make nests by bringing straw, cloth scraps, and other soft materials to a selected nook or box; they particularly are attracted to hayloft

Hayloft

A hayloft is a space above a barn, stable or cow-shed, traditionally used for storage of hay or other fodder for the animals below. Haylofts were used mainly before the widespread use of hay bales, which allow simpler handling of bulk hay...

s as nest sites. In birds it is known as "going broody", and is characterized by the insistence to stay on the nest as much as possible, and by cessation of laying new eggs. Marsupial

Marsupial

Marsupials are an infraclass of mammals, characterized by giving birth to relatively undeveloped young. Close to 70% of the 334 extant species occur in Australia, New Guinea, and nearby islands, with the remaining 100 found in the Americas, primarily in South America, but with thirteen in Central...

s do not exhibit a nesting instinct per se, because the mother's pouch fulfills the function of housing the newborns.

In humans

In human females, the nesting instinct often occurs around the fifth month of pregnancy, but can occur as late as the eighth, or not at all. It may be strongest just before the onset of labor

Childbirth

Childbirth is the culmination of a human pregnancy or gestation period with the birth of one or more newborn infants from a woman's uterus...

.

It is commonly characterized by a strong urge to clean and organize one's home and is one reason why couples who are expecting a baby often reorganize, arrange, and clean the house and surroundings.

Other uses of 'nesting'

The term 'nesting instinct' can also refer to the inclination of finalists to 'reserve' seats in libraries at Oxford University when they are not at their desks. This habit is frowned upon by the University authorities.