While a pregnant woman’s changing body is noticeable to the outside world, changes in the brain are much harder to measure. However, a new study suggests that neurological changes are just as profound. In other words, the sensation known as “pregnancy brain” is not what we thought — and it could actually be a good thing.
When a woman becomes pregnant, activity increases in the regions of the brain that control empathy, anxiety and social interaction. Gray matter in the brain becomes concentrated and there are structural changes in the areas that perceive the feelings and perspectives of others.1
The findings, published in the journal Nature Neuroscience, suggest that neurological changes in these parts of the brain promote bonding between mothers and their babies after birth and allow women to be more attuned to the needs of their infants. In a way, these changes are believed to prime women to become more sensitive, nurturing mothers.
The study, which included first-time mothers and women who had never been pregnant before, found that the more a pregnant woman’s brain changed, the more emotionally attached they were to their babies — a phenomenon that’s thought to last for at least two years after giving birth.
Moreover, the study found that the changes led to a heightened awareness of strangers. So that protective mama bear instinct that you’ve always heard actually kicks in during gestation. (Some mothers would argue that particular instinct lasts for life.)
In addition to more positive results, changes to the brain during pregnancy can also be responsible for negative effects such as anxiety and depression. About one in six women experience postpartum depression, and many more tip the scales toward obsessive behavior, such as repeatedly checking to see if baby is still breathing.2
Contrary to popular belief, the changes seen in the brain didn’t seem to have an effect on memory loss or verbal skills before or after pregnancy.
That’s not to say that pregnant women don’t have a good excuse for misplacing keys or missing appointments more than usual. Previous studies have suggested that surges in the levels of sex hormones during pregnancy could be to blame for lapses in concentration or memory.3 But researchers reviewing the newer findings suggest that this could simply be attributed to higher levels of stress and excitement in preparation for a new baby.4,5
Previous studies conducted on rats found that pregnancy caused the brain to form new neurons that boosted their sense of smell, potentially allowing them to identify their offspring.3 Women in love with that “newborn smell” on their babies could attest to that. Levels of oxytocin — the hormone that lights up the reward centers of the brain that make you feel happy — also increase during pregnancy and the postpartum period, making mothers more sensitive to the sound of their baby. In the brain, surges of this hormone look a lot like falling in love.6,7,8,9,10
So is it love at first sight when a mother meets her new baby? Science seems to think so.
1 Hoekzema et al., (2016). Pregnancy leads to long-lasting changes in human brain structure. Nature Neuroscience, 20(2), 287-296. doi:10.1038/nn.4458
2 LaFrance, A. (2015, January 08). What Happens to a Woman's Brain When She Becomes a Mother. Retrieved March 15, 2017, from https://www.theatlantic.com/health/archive/2015/01/what-happens-to-a-wom...
3 Pappas, S. (2011, December 28). Pregnancy May Change Mom's Brain For Good. Retrieved March 15, 2017, from http://www.livescience.com/17655-pregnancy-change-moms-brains.html
4 Belluck, P. (2016, December 19). Pregnancy Changes the Brain in Ways That May Help Mothering. Retrieved March 15, 2017, from https://www.nytimes.com/2016/12/19/health/pregnancy-brain-change.html?_r=1
5 Rice, K., & Redcay, E. (2014). Spontaneous mentalizing captures variability in the cortical thickness of social brain regions. Social Cognitive and Affective Neuroscience, 10(3), 327-334. doi:10.1093/scan/nsu081
6 Barrett et al., (2012). Maternal affect and quality of parenting experiences are related to amygdala response to infant faces. Social Neuroscience, 7(3), 252-268. doi:10.1080/17470919.2011.609907
7 Bartels, A., & Zeki, S. (2004). The neural correlates of maternal and romantic love. NeuroImage, 21(3), 1155-1166. doi:10.1016/j.neuroimage.2003.11.003
8 Bauman, M. D. (2004). The Development of Mother-Infant Interactions after Neonatal Amygdala Lesions in Rhesus Monkeys. Journal of Neuroscience, 24(3), 711-721. doi:10.1523/jneurosci.3263-03.2004
9 Baril, D. (2016, October 13). Why do you want to eat the baby? Retrieved March 15, 2017, from http://nouvelles.umontreal.ca/en/article/2013/09/23/why-do-you-want-to-e...
10 Abraham et al., (2014). Father's brain is sensitive to childcare experiences. Proceedings of the National Academy of Sciences, 111(27), 9792-9797. doi:10.1073/pnas.1402569111