Nearly 85 percent of women get pregnant at least once in their lifetime, and about 140 million women become pregnant each year.
Scientists have long known that pregnancy can lead to certain changes in the brain, but the specific neurological changes have not been very clear, so that "a pregnant fool for three years" this proverb is widely circulated. But is this really the case?
At the end of 2016, scientists analyzed pre-pregnancy and postnatal imaging data and found that pregnancy can indeed make brain structure different, especially in areas related to the mind, and the volume is actually reduced! This seems to support the idea of "pregnant stupidity".
But this study can only give people a partial understanding of the difference between the pre - and post-pregnancy brain.
Exactly what happens to brain structures and nerves throughout pregnancy is still unknown.
This may now be clearer than ever. A team including scientists from the University of California, Santa Barbara, has for the first time documented brain changes throughout pregnancy by scanning a mother's brain, and published the results in the latest issue of Nature Neuroscience.
In short, they found a mix of not-so-good and good changes. For the less good, human brain regions may shrink during pregnancy; But on the plus side, connectivity just got better. This change covers the vast majority of brain regions, and only a small part remains the same during the transition to motherhood.
The scientists selected a healthy 38-year-old woman for their analysis.
To capture brain changes throughout the pregnancy, they had 26 MRI scans and blood assessments throughout the pregnancy: from four scans in the first three weeks of pregnancy, to 15 scans in the third trimester of pregnancy, to seven scans two years after delivery, which is unprecedented in accuracy and comprehensive.
For comparison, eight control individuals who were not pregnant also underwent brain scans.
When compared, the scientists found that by the ninth week of pregnancy, the mother had developed a large decrease in cortical volume and thickness, especially in areas associated with social cognition;
Increases in white matter microstructure, ventricular volume and cerebrospinal fluid were also found. These changes should be associated with increased levels of estradiol and progesterone.
In contrast, the integrity of a microstructure called white matter increases throughout the first six months of pregnancy. This part is located deep in the brain and is normally responsible for facilitating communication between brain regions.
Some of these changes, such as reduced cortical volume and thickness, were still present two years after the mother gave birth; Other changes return to pre-natal levels about 2 months after delivery.
There is no doubt that scientists will need to further study the longer-term effects of pregnancy on the brain, as well as to expand the study group. But now, at last, there is a crucial understanding of the neurological changes that occur throughout pregnancy.
In science, this is one of the most complete maps of neuroanatomical changes in humans before, during, and after pregnancy; On a daily basis, it will help clinicians and expectant mothers better cope with the many changes in mental health, parenting behavior and the brain.
