Do Chocolate Lovers Have Sweeter Babies?
The Surprising Science of Pregnancy

A bright book of brain candy about the surprising science behind pregnancy


One spring night at the end of my second trimester, I dreamed my fetus ran away. I woke up to find myself in an embryonic curl, the curtains blowing and moonlight streaming in. As the ceiling fan above circled lazily, I remembered this: my renegade baby, pinkish-pale, dashing out into a delicate and infinite landscape; the irresistibly charming little imp hooting and hollering and kicking the cancan; and me in hot pursuit, bumbling and breathing heavily.

“Every pregnant woman has body and self taken over by a chthonian force beyond her control,” wrote the feminist writer Camille Paglia. “The so-called miracle of birth is nature getting her own way.” I fear she’s right. I feel my conscious, rational self isn’t calling the shots anymore. I’m inhabited by urges and appetites that are not my own.

I’ve asked myself: I’m not in control, so who is?

It’s the fetus—at least in some ways, some of the time. The little ones manipulate us long before they’re born. This helps explain some pregnancy weirdness, like how we might turn up our noses at delicacies we once loved (good-bye bitter greens, sayonara sardines) in favor of the sweet or simple foods of childhood. Some of us find ourselves
desperately drawn to all that is safe and familiar. Why the eagerness to bond with our mothers, siblings, and girlfriends? When did we lose our edge, finding ourselves less open and even distrustful of the foreign and exotic? Why do we suddenly read fear, anxiety, and anger so often and easily on other people’s faces?

Hormones are behind these developments. But who’s behind the hormones? It’s the unborn baby and her ambassador, the placenta. Changing Mom’s behavior is a fetus’s way of protecting her own interests: safety, food, and health.
I started researching this book before I got pregnant, wrote it as my baby girl grew inside me, and finished it several months after her birth. The nine chapters roughly span this time. A science writer and an expectant mom, I had been gripped by questions—some practical and others whimsical, some classic and others cutting edge—involving the science of pregnancy: Why are my dreams so vivid? Might what I eat now affect the baby’s tastes in life? Is stress sharpening my baby’s mind or dulling it? Could there be a hidden reason we conceived a girl and not a boy?

More and more questions bubbled up as the months passed. I ask whether pregnesia, or pregnancy amnesia, is for real. I explore whether there’s a Daddy Gene and what shapes maternal instinct. I question what they say about newborns looking like their dads. I wonder if it’s possible for my husband to nurse the baby. And by the way, are breast-fed babies really brainier? For answers, I’ve looked to hundreds of peer-reviewed studies and the researchers behind them. Evolutionary psychology, biology, social science, neuroscience, reproductive genetics, endocrinology—these scientific disciplines all touch on pregnancy, and I draw on them generously.

The science got weirder as I got rounder. I learned reasons that a partner’s odor might turn us off and why to have sex with him anyway. Expectant fathers often find themselves plumping up and even puking, conditions triggered by their hormones. What triggers these hormonal tides? It’s probably us—our behavior, or even our odor carrying chemical messages we produce only when pregnant.

A pregnant woman has more power than she realizes. Our ancestors believed that what we think, eat, and otherwise experience in pregnancy influence the baby in the womb—and there’s increasing evidence it’s true. Newborns are not blank slates. This is why scientists find it’s worth investigating whether a woman’s prenatal chocolate consumption might sweeten her baby’s temperament, why kids are born favoring their mother’s tastes and mother tongue, and how an expectant mom who keeps her competitive edge might sharpen her unborn baby’s mind. The mother’s sway over the fetus may begin at the moment of conception, or even beforehand, as I explore in the pages to come. Why else would bossy broads have more boys? And why do skinny chicks have more girls?

This book taps into the fascinating new field of epigenetics, the influence of environment on the behavior of genes. Recent studies in this emerging science reveal how blood sugar, stress and hormone levels, exposure to toxins, and even certain experiences alter how an unborn baby’s genes behave without changing their underlying sequence.

Epigenetics explains why babies of overeating moms, having developed in a womb larded with sugars and fats, may grow up to be hungrier, heavier, and even more harried than they’d be otherwise. It gives insight into why it’s foolish to frazzle a fetus, why smoking and starvation wreak havoc, and why our maternal instincts depend in part on how we moms were treated in babyhood. An epigenetic effect may even echo through the generations. If you ate a high-fat diet during pregnancy, for instance, your kids and grandkids might inherit a predisposition to diabetes. The dietary decisions your mother made when you were little more than an embryo could affect your baby too.

We’re all immensely curious about what our babies will be like, and many of the questions in this book address prenatal prediction. If a fetus kicks a lot, will he be the active, fussy type after he’s born? Might playing music or reading storybooks to our stomachs leave any impression? There are fortunes to be told by analyzing the baby’s fingers in the ultrasound, predicting her birth season, and listening to the patterns of her heartbeat.

Looking at pregnancy through Darwin’s eyes is intriguing—and even useful. I found instructive and thought-provoking theories on why we get morning sickness, why not to eat for two, and why a mother’s bubble butt is good for her child’s IQ. There are evolutionary reasons for why we can expect labor pains to intensify at night, how childbirth is both painful and forgettable, why we should seize the “golden hour,” the first sixty minutes after birth, how breast milk is mood milk, and what we should expect from our new Mommy Brain. (Chapter 9 lists practical tips.)

This is not a comprehensive book of medical advice like What to Expect When You’re Expecting. That’s been done and done well, and there’s no need for a rehash. While other pregnancy books are heavy on the how-to, this book focuses on the why—answering questions that our doctors won’t touch. I write for the curious, inspired, open-minded, information-hungry mother-to-be (and the expectant dad too) who is seeking a deeper understanding of what’s happening to her. I’ve presented the topics in an easy-to-browse question-and-answer format for the time-limited and commitment-phobic. It’s curiosity driven: flip to the topics that interest you. I’ve tried to pack a mother lode of information into a format that you can read randomly and in small doses. I write with insomniac nights and waiting rooms in mind.

In the end, we learn not only about what’s happening to our own bodies and minds during pregnancy, but also something about biology and human nature. It’s all thanks to researchers who have peered into innumerable wombs, counted kicks and tiny heartbeats, stretched headphones over pregnant bellies, and tracked men and women from the time they were embryos. They’ve crunched mountains of data and imagined what happened on the savannas where our ancestors evolved. Driven by curiosity and wonder, these scientists have analyzed the hormones of expectant parents, the genes of placentas, the fetus-friendly properties of semen, the flavors in amniotic fluid, the mind-control properties in tears, and the mood milk of laughing mamas. They’ve asked new mothers to press dirty diapers to their noses and tuck sweat collection pads in their bras. They’ve even entered maternity wards to find the truth about whether chocoholics have sweeter babies. It’s all in the spirit of that one bold word that resonates with parents and children everywhere: Why?

A lively, accessible romp through the science of pregnancy...with wit, personal anecdotes and playful humor.

(starred review)

Utterly fascinating...and a great read.

Christiane Northrup, M.D., ob/gyn physician and author of Women's Bodies, Women's Wisdom and The Wisdom of Menopause

Delightful! This book is destined to become every woman's -- and man's -- secret guide to pregnancy. A must read.

Louann Brizendine, M.D., neuropsychiatrist and author of The New York Times bestsellers: The Female Brain and The Male Brain

...A wide array of subjects expectant parents will find utterly captivating...Readers will be entertained and fascinated by this text from start to finish...Pincott writes with humor and vibrancy, bringing science to life.

Publisher's Weekly

A fascinating tour through the science of pregnancy...answers questions, shares stories, and passes on insights gleaned from her exhaustive research...Everything you wanted to know about pregnancy but were afraid to ask.

Annie Murphy Paul, author of Origins: How the Nine Months Before Birth Shape the Rest of Our Lives

A survey of cutting-edge research...full of useful thinking that will inform and comfort expectant mothers (and fathers) everywhere.

Cacilda Jetha, M.D., co-author of Sex at Dawn