"Long before it's in the papers"
November 17, 2011

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Mom’s mood may affect developing fetus

Nov. 17, 2011
Courtesy of the Association for Psychological Science
and World Science staff

De­pres­sion in a preg­nant wom­an can change how the ba­by de­vel­ops af­ter birth, new re­search sug­gests—but the ef­fect is far from simple.

As a fe­tus grows, it’s con­stantly get­ting chem­i­cal sig­nals from its moth­er, not­ed the au­thors of the stu­dy, pub­lished in the jour­nal Psy­cho­log­i­cal Sci­ence.

In re­cent dec­ades, sci­en­tists have found the en­vi­ron­ment in the womb is very im­por­tant to a fe­tus. Smok­ing and drink­ing can be dev­as­tat­ing. Oth­er ef­fects are sub­tler; peo­ple who were born dur­ing the Dutch fam­ine of 1944, most of whom had starv­ing moth­ers, were iden­ti­fied as likely to have health prob­lems like obes­ity and di­a­be­tes lat­er.

In the new stu­dy, Uni­vers­ity of California-Irvine sci­en­tists re­cruited preg­nant wom­en and checked them for de­pres­sion be­fore and af­ter they gave birth. They al­so gave the ba­bies tests af­ter birth to see how well they were de­vel­op­ing.

What made a dif­fer­ence to the ba­bies was wheth­er the en­vi­ron­ment was con­sist­ent be­fore and af­ter birth, the re­search found. The health­i­est ba­bies were those who ei­ther had moth­ers who were healthy both be­fore and af­ter birth, and those whose moth­ers were de­pressed be­fore birth and stayed de­pressed af­terward. What slowed the ba­bies’ de­vel­op­ment was chang­ing con­di­tion­s—a moth­er who went from de­pressed be­fore birth to healthy af­ter or healthy be­fore birth to de­pressed af­ter.

“We must ad­mit, the strength of this find­ing sur­prised us,” said Curt A. Sand­man, one of the re­search­ers. A cyn­i­cal in­ter­preta­t­ion would be that if a moth­er is de­pressed be­fore birth, you should leave her that way for the well-be­ing of the in­fant, Sand­man not­ed. But he ar­gued that a “more rea­son­a­ble ap­proach” would be to treat wom­en who have pre­na­tal de­pres­sion.

“We know how to deal with de­pres­sion,” he said, but the prob­lem is that wom­en are rarely screened for de­pres­sion be­fore birth.

In the long term, hav­ing a de­pressed moth­er could lead to neu­ro­lo­g­i­cal prob­lems and psy­chi­at­ric dis­or­ders, Sand­man said. In an­oth­er stu­dy, his team found that old­er chil­dren whose moth­ers were anx­ious dur­ing preg­nan­cy have dif­fer­ences in cer­tain brain struc­tures. It will take stud­ies last­ing dec­ades to fig­ure out ex­actly what hav­ing a de­pressed moth­er means to a child’s long-term health, he added.

“We be­lieve that the hu­man fe­tus is an ac­tive par­ti­ci­pant in its own de­vel­op­ment and is col­lect­ing in­forma­t­ion for life af­ter birth,” Sand­man said. “It’s pre­par­ing for life based on mes­sages the mom is pro­vid­ing.”

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Depression in a pregnant woman can affect how the baby develops after birth, new research indicates. As a fetus grows, it’s constantly getting chemical signals from its mother, noted the authors of the study, published in the journal Psychological Science. In recent decades, scientists have found the environment in the womb is very important to a fetus. Smoking and drinking can be devastating. Other effects are subtler; people who were born during the Dutch famine of 1944, most of whom had starving mothers, were identified as likely to have health problems like obesity and diabetes later. In the new study, University of California-Irvine scientists recruited pregnant women and checked them for depression before and after they gave birth. They also gave the babies tests after birth to see how well they were developing. What made a difference to the babies was whether the environment was consistent before and after birth, the research found. The healthiest babies were those who either had mothers who were healthy both before and after birth, and those whose mothers were depressed before birth and stayed depressed afterward. What slowed the babies’ development was changing conditions—a mother who went from depressed before birth to healthy after or healthy before birth to depressed after. “We must admit, the strength of this finding surprised us,” said Curt A. Sandman, one of the researchers. A cynical interpretation would be that if a mother is depressed before birth, you should leave her that way for the well-being of the infant, Sandman noted. But he argued that a “more reasonable approach” would be to treat women who have prenatal depression. “We know how to deal with depression,” he said, but the problem is that women are rarely screened for depression before birth. In the long term, having a depressed mother could lead to neurological problems and psychiatric disorders, Sandman said. In another study, his team found that older children whose mothers were anxious during pregnancy have differences in certain brain structures. It will take studies lasting decades to figure out exactly what having a depressed mother means to a child’s long-term health, he added. “We believe that the human fetus is an active participant in its own development and is collecting information for life after birth,” Sandman said. “It’s preparing for life based on messages the mom is providing.”