A recent study looked at paternal and maternal psychiatric history and risk of preterm and early term birth. It was a nation-wide study using Swedish registers.
“It has been known for some time that women who are clinically anxious or depressed are more likely to deliver a child prematurely,” study author Michael E. Silverman told us. “Indeed, considerable evidence now exists showing a relationship between various psychiatric illnesses and the likelihood of delivering a premature infant.”
Preterm birth is a significant public health concern, given its association with numerous adverse childhood outcomes, many extending into adulthood including behavioral problems, cognitive issues, mental health conditions, neurological disorders, asthma, increased likelihood of infections, and potential visual challenges.
“Historically, society has blamed mothers for these obstetric and developmental outcomes,” Silverman told us. “In the 1940s, it was believed poor or deficient mothering behaviors caused autism and schizophrenia. More recently, food allergy, hyperactivity, depression, and even transsexualism have been blamed on the mother.”
There were three primary objectives of the study: First, researchers sought to explore the risk of preterm birth associated with the father’s psychiatric history; second, to determine the risk of preterm birth when both parents have a history of psychiatric illness; third, to clarify the full range of psychiatric disorders and their association with preterm birth.
Using the Swedish health and population registries, researchers explored approximately 1.5 million births, representing all live deliveries to Nordic-born individuals over 19 years (1997-2016). Notably, the Swedish registries cover the country’s entire population; therefore, this was a population-inclusive study.
“Based on the combination of the previous work in this area, and the understanding that psychological illness in the gestational parent is associated with a higher risk of premature delivery, we had reason to believe that we would see increased risk when the non-gestational partner also had a psychiatric illness,” Silverman told us. “But, as far as we know, this is the first nationally inclusive, large population-based study to comprehensively examine the full gestational range by psychiatric diagnoses for both parents.”
While the relationship between maternal psychiatric illness has been established, less is known about the paternal role in preterm delivery, and even less is known about the possible role of the various types of psychiatric illness. To better understand the underlying mechanisms associated with psychiatric illness and preterm delivery, it is essential to disentangle psychiatric history contributions from both the gestational and non-gestational parents.
The study was conducted by analyzing data on all live births to Nordic parents in Sweden between 1997 and 2016 using the Swedish Health and Population Registries. Psychiatric diagnoses were obtained from the National Patient Register and data on gestational age from the Swedish Medical Birth Register.
“There were 1.5 million births in the cohort, of which 15% were born to parents with a diagnosis,” Silverman told us. “We observed a trend towards earlier gestational age in offspring born to parents with psychiatric disorders.”
For parents without a diagnosis, 5.8% of babies were born preterm. A paternal diagnosis increased the risk to 6.3% of births, and a maternal diagnosis increased the risk to 7.3%. However, when both parents were diagnosed with a psychiatric illness, the risk of preterm birth was greatest, affecting 8.3% of births.
“The dose-dependent pattern of premature delivery observed with the increasing number of co-occurring psychiatric disorders from different diagnostic categories in the non-gestational and gestational parents was an interesting observation,” Silverman told us. “Preterm birth is a public health concern. Given the relationship between psychiatric history in either parent and preterm delivery, we believe it is essential for those responsible for delivering babies, namely obstetricians, to ask their patients about any relevant psychiatric history to plan for possible obstetric complications. Future studies should examine whether additional social support and prenatal care for families with psychiatric histories could impact gestational age.”