This article was originally published on February 7, 2022.
When I noticed our 14 year old son was drinking more water than usual, I told my husband that sudden thirst could be a sign of diabetes. We’re in the middle of a heat wave, he replied. A few days later, our son seemed unusually tired and I raised the possibility of diabetes again. Our son’s summer days were filled with sports games and building for a play, my husband replied.
After my son told me he had been up all night to go to the bathroom, I finally called his pediatrician. It turned out that her blood sugar was dangerously high. Already thin, he had lost 11 pounds in three months, despite eating more than usual. As we headed to the children’s hospital for emergency treatment I told the pediatric nurse I suspected diabetes but didn’t call because my husband kept finding logical explanations. “Mother’s instinct is always right,” the nurse said.
Is maternal instinct real?
But is there such a thing as maternal instinct? Not exactly, say the scientists. It’s true that when pregnant, breastfeeding and caring for a new baby, mothers go through hormonal changes that prepare them to care for them, says Helena Rutherford, a researcher at the center for children’s studies at the Yale School of Medicine. These hormones, including oxytocin or the “love” hormone, promote bonding between infant and mother.
And after birth, mothers are aided by the baby’s cues rather than just relying on an innate sense of her child’s needs. So new mothers don’t necessarily have all the answers right away.
“It’s a process. It’s not a switch – I don’t think science supports the existence of maternal instinct,” says anthropologist Sarah Blaffer Hrdy, who has authored books on family ties, including Mothers and others.
Learn more: Crocodiles are particularly good mothers
The brain undergoes significant transformations during pregnancy, including structural changes that can persist for up to six years later, says Elseline Hoekzema, a neuroscientist at Leiden University in the Netherlands. She and her colleagues found that the brains of pregnant women experience a reduction in gray matter volume, as shown in a 2016 study. Natural neuroscience study, which could be how the body prepares them to care for infants.
Adolescence also involves significant reductions in gray matter, which are driven by some of the same hormones that also increase during pregnancy, Hoekzema wrote. In the adolescent brain, neural networks are finely tuned to enable emotional, social and cognitive developments.
And among pregnant women, scientists observed the most apparent changes in brain regions associated with social processes; this could represent a specialization in the brain that enables the impending transition to motherhood, Hoekzema noted.
It’s possible that the more volume a woman loses in a key region of the brain’s reward circuitry, the more strongly that region responds after seeing her newborn baby, a 2020 study suggests. Psychoneuroendocrinology article co-authored by Hoekzema.
These changes during pregnancy can help a mother care for her baby – a phenomenon also seen in other mammals. For example, mother rats become better at catching crickets. As with humans, these adaptations enable important maternal skills, such as recognizing her baby’s needs or spotting an outside threat.
Maternal hormones and association with maternal instinct
Hormones associated with pregnancy and caregiving, which certainly seem to be a source of what many would call maternal instinct, can also increase in people other than the child’s mother. Although it is widely known that the bodies of breastfeeding mothers produce oxytocin, which has a calming effect, fathers, adoptive parents, grandparents and other caregivers also experience biological changes due to the passage of time. with children, says Rutherford of the Child Study Center.
In addition to breastfeeding, carrying a baby next to your body (also called kangaroo care) also increases oxytocin levels. “It’s a really powerful hormone,” Rutherford says. “It’s my instinct that you don’t have to go through pregnancy” to be attuned to your baby’s needs and bond powerfully, she says. “The motivation to care is enough.”
From an evolutionary perspective, mothers have served as caregivers, protectors and nurturers, she says. Mothers develop heightened anxiety about their children’s well-being and give them special attention, says Rutherford, which contributes to the survival of the species.
But new evidence helps provide more nuance: Researchers have noticed that during the first six months of their child’s life, new mothers and fathers experience increased levels of oxytocin. Moreover, the parents do not seem to show any difference in oxytocin levels, as demonstrated in a 2010 biological psychiatry study. The research also suggested that the source of oxytocin increases may vary between men and women; men can experience increases in the hormone through high levels of nurturing touch, while women can experience it through lots of loving touch.
The brains of gay fathers are also thought to show similar responses to their infants compared to heterosexual parents, according to research published in PNAS in 2014. The more time they spend with the baby, scientists have found, the greater the connection between emotional and cognitive structures. Similarly, adoptive mothers’ oxytocin levels increased in response to the infants they were caring for, similar to biological mothers, as shown in a 2013 study. child development paper.
It takes a village
Humans did not evolve in nuclear families, says Hrdy, the anthropologist, but rather in extended families. Today, babies can attach themselves to about five people in addition to their mother, says Hrdy, who co-wrote a chapter on the subject in the book Evolutionary Perspectives on Early Childhood.
She uses the term allomothers to refer to aunts, uncles, grandparents, and older siblings who help care for young children. Hello means “other than” in Greek. Early in human history, postmenopausal women gathered more food for the family than mothers capable of childbirth, and they played a vital supporting role in family survival. Access to a social safety net always enables mothers to better meet the needs of their children, even if this scenario is more common in wealthy families.
In the worst-case scenario, infanticide can result from a lack of support, she says, and may explain why women abandoned their babies throughout history. It offers similar reason to explain why the behavior continued in modern times. After all, being a parent can be extremely difficult on its own. Rutherford says she would like to see society’s idea of motherhood “move away from this idea that motherhood is all about joy and rainbows.” It’s cognitively demanding, emotionally demanding. It’s as stressful as it is joyful. »
The level of a woman’s “maternal instinct” — if such a thing exists — does indeed depend on how much parenting help she receives, says Rutherford, as well as how she was raised, how her knowledge of caregiving and the ease or difficulty of her pregnancy and childbirth experiences. .
Overall, researchers seem to agree that some parents, regardless of gender, are more aware of their children’s moods and health fluctuations than others. What passes for maternal instinct may actually be the result of a combination of motivation and quality time spent with their children – another reason why some believe maternal instinct is a myth.
But “how uniquely maternal or feminine it is, we don’t really know,” says Hrdy, as more research is currently underway. “It’s so early.”