Mothers are made, not born. Virtually all female mammals, from rats to monkeys to humans, undergo fundamental behavioral changes during pregnancy and motherhood. 

Although scientists have long observed and marveled at this transition, only now are they beginning to understand what causes it.New research indicates that the dramatic hormonal fluctuations that occur during pregnancy, birth and lactation may remodel the female brain, increasing the size of neurons in some regions and producing structural changes in others. 

The cortisol, which typically rises with stress and can have a negative impact on health, may have a positive effect in new mothers. By raising cortisol levels, the stress of parenting may boost attention, vigilance and sensitivity, strengthening the mother-infant bond. 

Other studies have pointed to a possible long-term effect of motherhood. Women who had been pregnant at or after the age of 40 were four times more likely to survive to 100 than women who had been pregnant earlier in life. 

But can these skills transfer from the nursery to the boardroom?Scientists do not yet know the answer, but studies indicate that the human brain is remarkably plastic: its structure and activity can change when a person is confronted with a challenge.   

·                It was summarized of Magazine “Scientific American”, January 2006