When - and if - women want to have babies has always been a hot topic of discussion.
Many women say that they’re not ready for such a huge life transition, putting the needs of a tiny human being before the needs of their own.
New research suggests that we shouldn’t worry about this transition quite as much as we do, though, since becoming a mum automatically rewires your brain to put your baby first.
The power of motherhood can subconsciously programme your brain to put your baby before anything - including drugs - says the scientists at the University of Massachusetts leading the study.
Corresponding author Dr Mariana Pereira, found two specific areas of grey matter that are behind the phenomenon, which she hopes will help women improve their mental health during pregnancy and early motherhood - also known as the fourth trimester.
“There are powerful tools, such as brain stimulation methods and a technique called chemogenetics that can manipulate the activity of discrete brain structures.
“These have good translational potential for psychiatric disorders - including drug use,” Dr Pereira said.
Simply being able to understand how and why the brain prioritises our offspring is a big step in learning more about the mental health of new mothers.
This research has also been eye-opening in beginning to understand and treat addiction.
“There are very limited treatments for addiction. Understanding the brain circuits underlying natural resistance to drug seeking provides critical knowledge that has implications for everyone with a substance use disorder,” Dr Pereira added.
A woman’s brain goes through multiple changes after giving birth, but perhaps the most interesting changes are in the pre-frontal cortex - which is responsible for the control of both addictions and parenting.
It filters and represses multiple streams of information - such as drug-using mothers picking between their new child or drug-seeking.
“Motherhood takes over the brain's decision-making regions to prioritise caring for offspring,” Dr Pereira explained, having studied this behaviour in rats - who also use the pre-frontal cortex in parenting and addiction.
“The brain recruits the discriminating powers of the infralimbic (IL) cortex (a part of the pre-frontal cortex) to prioritise offspring over competing desires.”
Read more: Lauren Pope shares her pregnancy anxieties
It is estimated around one in 500 babies in hospitals in England is born dependent on drugs their mother took while pregnant.
An inactivation of the PrL cortex, another part of the pre-frontal cortex, saw a shift in rats towards their children and away from their addiction.
“These findings refine our understanding on how the maternal brain processes information about offspring and cocaine, how this information is integrated to bias decision making, and have implications for the development of intervention strategies to prevent drug relapse in new mothers,” Dr Pereira said.
Pregnancy will see women experience a flood of oestrogen which is greater than for the whole of the rest of their lives, yet there is scarce research into the impact it can have on the human brain.
This research is a great step towards understanding how the brain works during pregnancy and beyond.