SINGAPORE - Singaporean women who feel stressed, depressed or anxious while pregnant may give birth to children who are more easily distracted and have poorer memory, according to the preliminary findings of a landmark study.
The mental distress may even cause the babies to be born physically shorter, which is an issue as Asian children tend to have higher IQs when they are born longer, heavier or with larger head circumferences.
Scientists from the Agency for Science, Technology and Research's Singapore Institute for Clinical Studies (Sics) said more research is needed, but the findings suggest that looking after expectant women is critical to ensuring their children get the best start in life.
"To really help our children grow, we need to take care of soon-to-be mothers and their families early, even before any difficulties arise," said principal investigator Anne Rifkin-Graboi.
Sics partnered KK Women's and Children's Hospital and the National University Health System (NUHS) in 2009 to study how metabolic diseases arise from early life.
The research then expanded into other fields, with the help of the National University of Singapore's Department of Biomedical Engineering.
The Gusto (Growing Up in Singapore Towards Healthy Outcomes) project had some 1,200 expectant women, and the researchers are still tracking their children, who are now three to 41/2 years old.
The pregnant women filled out questionnaires about their mental well-being, and the infants' brains were scanned a week after birth.
As the babies were only a week old, any differences between their brains were "probably" due to their mothers and not their life experience, said Sics acting executive director Chong Yap Seng.
The scientists found that the babies born to women who felt anxious or depressed during pregnancy were shorter, and their brains' limbic regions were less developed compared to their peers'.
The limbic system is linked to memory, stress regulation and emotional reactions and also works closely with other parts of the brain involved in decision-making.
When these children were six months old, they were more easily distracted and had poorer memory, experiments' preliminary results showed.
For example, they were shown how to assemble a toy and then asked to do it. In another experiment, the researchers played background sounds to distract the babies while playing with them.
"What we think happens is, if the mother is stressed or depressed during pregnancy, she is signalling to her baby that the outside environment is stressful," said Associate Professor Chong, who is also a senior consultant in National University Hospital's Department of Obstetrics and Gynaecology.
"So the baby makes sure it can pick up threats easily. It becomes very aware of its surroundings but it can't focus as well," he said.
The researchers said they hoped the data would spur more support for pregnant women.
"They should also not feel guilty about taking time to relax, even if it comes at the expense of having a sparklingly clean floor," said Dr Rifkin-Graboi.
But obstetricians and gynaecologists said the findings may unintentionally make the women more anxious.
"Some of them may worry about how much worry is detrimental," said Dr Ann Tan, a foetal maternal specialist who has a practice at the Women & Fetal Centre.
"As all mothers are naturally anxious about their pregnancies, this may be an additional source of stress."
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