I had every intention of taking a nice long, hot shower this morning. My daughter Nora was in her swing, a surefire way to buy an hour or more of quiet time, and I thought I might even shave my legs. And then, as I was lathering my hair, it hit me. No, not the sound of crying, but the realization that the swing was in full view of the window in our front door. What if someone broke the glass, wrenched open the door, and stole the baby while I was in the shower? What would I do?

I fully recognized how ridiculous this was. Even supposing that baby-snatching miscreants were abroad in our sunny neighborhood at eight o'clock on a Saturday morning, there was no way they could pull off their dastardly plan without my hearing either the breaking glass or the wailing of a baby whose happy little nap had been disturbed by thugs. Our house just isn't that big. So I finished washing my hair, but skipped the leg-shaving (yet again) just so I could go check on her.

My truncated shower had evidently foiled the kidnappers, because there Nora was, sweetly sleeping as she rocked back and forth. Her head was slumped to one side and a pacifier dangled precariously out of her mouth. The angle of her head made it hard to see the rise and fall of her little chest, so I propped her up, just to make sure she was breathing. A sleepy little grunt told me what I already knew: that she was fine.

Of course she was fine. She has been every one of the countless times, in the eleven weeks since her birth, that I've tiptoed over to the crib while she naps to listen for that quiet little inhale and exhale, and every time I've laid a hand on her tiny chest in the middle of the night when I can hardly see her in her bassinet. None of her tiny sneezes has portended a case of diphtheria. The occasional green tinge of the goop in her diaper is perfectly normal. Her car seat is installed so that it can't move an inch. Everything is fine, but I live in fear that one day it won't be, because if something goes wrong—by which I mean, translated out of euphemism, if I lose her, if she dies—I don't know how I can live.

New motherhood has brought plenty of changes to my life, but perhaps the greatest of them is that there is now something I fear more than my own death: hers. It's a deep-seated dread, the worst thing I can imagine, and despite the occasional paranoid dash out of the shower, I try not to dwell on it. I've managed to refrain from random worried calls to the pediatrician's office. When my baby smiles or coos or latches on hungrily to my breast, I can see that she is the picture of health. But that undercurrent of fear is always there, rising coldly to the surface when I'm tired or feeling vulnerable, when a well-meaning friend emails me information about preventing SIDS, when I see a story in the paper about an ill child. It's the flip side of love, a chill that underlies the warm current of joy and astonishment that first washed over me when I was handed the naked, squirming, slimy, bluish creature I'd just pushed into the world.

The fear followed the love quickly. That bluish tinge, and some difficulty breathing, meant that Nora was rushed to the nursery before I'd gotten a good look at her. Strangely, my worry during those four hours that she stayed in the nurses' care was not that about the breathing—the doctor told me that it was normal, that many babies have fluid in their lungs at the start—but that she had the wrong number of fingers and toes. She didn't, as my husband was soon able to assure me. He had followed her to the nursery and could also tell me that she quickly started breathing better and "pinked up" nicely, as the nurses put it.

Truth be told, the fear really preceded the love. Prenatal care and books on pregnancy seem to emphasize everything that can go wrong. At eight weeks pregnant, miserable and nauseated on a long-planned trip to London, I convinced myself I was miscarrying. I wasn't, but I was predictably nervous and sure that an unnamed something was wrong before every checkup, only to be reassured by my wonderful obstetrician.

Still, the message of everything I heard or read seemed to be that I was constantly on the verge of killing! my! baby!, or at least causing mercury poisoning by eating a tuna sandwich. (Never mind that I used to play with the quicksilver balls from broken glass thermometers, and I seem to be okay, if a little anxious.)

I started to wonder how the human race had survived this long, especially when my husband and I took a class on basic baby care through our hospital. I thought we'd be diapering dolls, getting advice on dressing infants, and hearing yet another pitch for breastfeeding. Instead, the class, condescendingly taught by an evidently battle-scarred nurse, focused heavily and gorily on dangers to infants, scary childhood illnesses, and the like, with special attention to ways in which babies can smother or strangle themselves if parents aren't extremely careful. The message seemed to be that babies emerge from the womb with a lemminglike determination to do themselves in, and only constant vigilance combined with long experience (which we as nervous new parents-to-be didn't have) could possibly prevent them. My husband spent the class with his head in his hands; I spent it composing imaginary letters of complaint to the hospital administration in my head. Naturally, I wanted to know about ways to raise my baby more safely, but what I didn't want was the suggestion that there was little I could do to help her survive a dangerous world.

It may be that in the long run that's true. I can't protect her forever, nor would I want to. Right now, however, there is a sweet simplicity in keeping her safe. Her needs are elemental: food, shelter, air. The first and second we provide, the third she gets all for herself in her first and most basic act of independence, having drawn breath reliably and smoothly ever since that slightly shaky beginning.

In eleven weeks, my little girl has stopped seeming so new and fragile to me, and as a mother I don't feel quite so new or fragile either. Taking care of her is a routine governed by her needs, pleasant but already unremarkable, and the miraculousness of her growth and birth takes a back seat to the predictability of her days. I don't watch every second for each breath or worry that she hasn't eaten for three hours. And I do my best to shake off the fearmongering that crops up in the headlines or in childcare books and focus instead on the indescribable love I have for her.

I give Nora what she needs from me, and the rest is up to her. Observing her instincts teaches me that her will to live, her urge to grow, is tremendously powerful. Her gaping mouth is hungry for the milk that rushes from me to fill her. Her little body snuggles firmly into the crook of my arm, seeking warmth and comfort. And always, the quiet rhythm of her breath continues on, a sound so faint I hold my own breath to hear it.