The furthest thought from most expectant parents’ minds is that their unborn baby will someday have aggressive feelings and will struggle to master them.

It’s a shock later when they discover that the baby who once seemed so fragile will need help balancing her need for self-assertion with self-control. Yet even during pregnancy, a mother-to-be notices the unborn baby’s movements in her womb.

“She seems to have a mind of her own,” a pregnant woman might say to her husband.

Even before a baby is born, parents are trying hard to get to know her. Is all this kicking and swimming around the earliest instance of self-assertion? No, not as far as anyone can know.

Just as the placenta controls the nutrients that the fetus can take in, the uterine walls limit the motions that the unborn child can “try out” and “practice.”

As a result, her movements become forced into predictable patterns — as a response to the bright lights and loud sounds that make their way into the womb during the last part of pregnancy. A fetus reacts to stimulation with a startle, a squirm or a large stretch.

What does this process have to do with learning about self-control? Perhaps not much. But it’s intriguing to imagine that a fetus might already be learning to contain its responses and tune out bright lights and loud sounds when necessary.

Turning away from such stimulation, or thumb-sucking, may be the unborn baby’s first opportunity to respond to the environment. Is it too much of a stretch to see the baby’s active role in birth as the first act of self-assertion?

No longer contained by the womb, no longer fed through the placenta, the new baby must learn to express her needs and to enlist the environment to help her survive. The earliest feelings — hunger, cold, discomfort, fatigue, pain — will lead her into action. She finds that if she cries, she can get her hunger satisfied. When she looks into your eyes, reaches out to you, softens and molds into you when you cuddle her, she makes you fall hopelessly in love — and eager to nurture her.

When she whimpers, startles and makes angry, dissatisfied faces, someone will wrap her or hold her to calm her down. Will these earliest experiences help her learn to handle such feelings later?

The newborn already has some control over her sleep and awake states, and the fussy and drowsy states in between. Not long after birth, she can stay alert and pay attention for short periods. She’ll look at the walls of her bassinet or gaze into your eyes.

But watch a newborn wake up and start to cry. She may finger her satin-bordered blanket or suck on her fist. These are some of her earliest ways of controlling herself and soothing herself. Already she’ll be learning from the comforting you offer, which, in turn, also helps her stay in control.

When the newborn has absorbed as much as she can of the new sights and sounds around her, she may fall apart. She’ll sob, turn red and sometimes even seem to gasp for breath.

Then she may go to sleep. But she may even go to sleep before she starts crying. This is her first way of escaping all the commotion when she needs to. Then she can stay asleep, even if there is more noise and activity around her. She is equipped with the capacity to handle sights and sounds through a process called “habituation” (shutting down responses over time to intrusive stimuli).

The newborn is learning how rewarding it is to get what she needs — milk by crying, sleep by shutting down, attention and comfort by being active and out of control. Just as important, she is learning how to manage her six awake and sleep states (deep sleep, light sleep, drowsy, alert, fussy and crying).

She is learning to stay asleep when she needs to rest and release tension — and to stay awake so she can interact with her new world when she wants to know more about it or to help caregivers learn about her. This reaction is one of the first signs of self-control.

A baby cycles from deep sleep through light sleep, then into fussing, and then alertness for a period. One can watch a newborn baby working to control her motor activity when she suppresses disturbing startles so she can pay attention to her parents’ voices or faces.

After a period of alertness, taking in her world, or reacting with rapt attention in this rewarding state, she will begin to fall apart. She may seem to cry angrily, demandingly. What should you do?

1. Quiet her with your insistent voice, or by holding her arms.

2. Swaddle her so that she can’t startle and become frantic with her out-of-control jerking.

3. Pick her up, rock her gently, contained in your arms, and even offer her a clean finger to suck on.

4. Feed her and put her to bed.

Parenting is a process of trial and error. After your efforts, over and over, to find the response that works, the baby will gradually develop the expectation that when she acts, she will receive an appropriate response. She’ll know she can count on your help to get back in control.

Questions or comments should be addressed to Dr. T. Berry Brazelton and Dr. Joshua Sparrow, care of The New York Times Syndicate, 620 Eighth Ave., 5th Floor, New York, N.Y. 10018. Questions may also be sent by email to:

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