Depression is the leading cause of disability worldwide and it is well known that there are strong links between parental and child depression. Understanding this relationship is key to trying to prevent intergenerational transmission. Worldwide, one in five women suffers from postpartum depression.
A new study published in BJPsych looked at maternal and paternal depression and child mental health trajectories.
“Our study is about tracking mood over time in children of parents who were depressed in pregnancy and/or after birth,” study author, Professor Rebecca Pearson of Manchester Metropolitan University/University of Bristol told us.
Pearson is Senior Lecturer in Psychiatric Epidemiology at the Centre for Academic Mental Health, School of Social & Community Medicine at the University of Bristol.
Postpartum depression isn’t the only mental health condition which can affect women, men, or birthing persons during the perinatal period (conception to one year postpartum). Other mental health conditions include prenatal and/or postpartum anxiety, obsessive compulsive disorder, panic disorder, post traumatic stress disorder, bipolar disorder, and in rare cases, about 1-2 in 1000, psychosis.
“We were interested in whether there were different patterns in offspring mood over time which might tell us something about how and when parents depression influences that of their children,” Pearson told us.
While some countries and jurisdictions have universal screening for perinatal mental illness, many do not. Many countries and jurisdictions struggle with timely access to treatment. Evidence-based treatment includes therapy and/or medication. Perinatal mental illness can range from mild to severe.
The researchers had several hypotheses, including that antenatal exposure would be associated with a particular pattern of risk to the offspring due to the potential impact of prenatal stress on fetal development. They also hypothesized that because of this fetal pathway of risk, maternal depression would be associated with greater risk than paternal depression.
“We used repeated measures of parental (mother and father) and child depression to model associations between different timings of parental depression with trajectories of child depression as they grow up,” Pearson told us. « We looked at associations both with overall levels of child depressed mood and with the rate at which depression scores increased over time as the child reached adolescence and adulthood.”
Researchers found that (as compared to offspring of non depressed parents), offspring of depressed parents had higher levels of depression themselves across time points. They also found that children of parents depressed at both antenatal and postnatal timings had the highest depression scores. They found that offspring of mothers depressed postnatally had scores that went up by more points each year than offspring of non depressed mothers.
“The results are consistent with a growing evidence base that exposure to chronic or repeated episodes of parental depression carries the greatest risk to children,” Pearson told us. “The different patterns according to whether the parent was depressed in pregnancy or after birth are intriguing and deserve follow up. We think they are consistent with there being different pathways of risk, for example postnatal depression may confer more of a risk via parent child interaction. The results further highlight the need for screening for parental depression to intervene early and prevent risk to the child.”