A new study published in the Journal of Affective Disorders has confirmed the last decade of research that has found mothers of preterm infants are at a higher risk for postpartum depression.
“We believe that these results highlight the importance of maternal mental health care among preterm infants´ mothers,” study author, Juliana Figueiredo told us. “Preterm birth is a global public health issue and we are usually aware of the challenges that this condition brings to the babies, as rates of morbidities and mortality among preterm babies are high. However, there is a growing literature of the impacts of preterm birth for parents and our findings reinforce the need of maternal mental health care among mothers of preterm infants.”
The World Health Organization defines preterm birth as childbirth that occurs before the 37th week of pregnancy. Pregnancy usually lasts 40 weeks. Extremely premature is categorized as a birth that happens at less than 28 weeks while a moderate to late preterm birth happens between 32 and 37 weeks.
Studies have shown that the survival rate of preterm births at 24 weeks is 20 to 35 per cent. For babies born at 25 weeks, the survival rate is 50 to 70 per cent and 90 per cent for babies born at 26 to 27 weeks. Preterm births is the leading cause of neonatal deaths worldwide and can put a considerable amount of stress on new parents.
The current study was a systematic review and a meta-analysis of the last decade evidence on the association between preterm birth and postpartum depression. Due to the results of their study, Figueiredo and fellow study authors recommend mothers of preterm infants be assessments for postpartum depression 15-90 days following birth as this has been identified as the time period with the highest risk for developing maternal mental illness following a preterm birth.
“We were willing to critically analyze the studies that explored such association and to find out whether there was evidence of preterm birth as a risk factor for postpartum depression,” Figueiredo told us. “We were expecting to confirm the association between preterm birth and postpartum depression. We also expected to find out that different methodological approaches would impact on the results, as findings in this field did not seem to be consistent.”
The hypothesis was that preterm birth would be a risk factor for postpartum depression. Due to the growing scientific interest in maternal mental health, especially in postpartum depression, many studies have been developed in the past decade and researchers wanted to confirm the association.
“I have been working with maternal mental health in the perinatal period as a psychotherapist for the last few years, especially with postpartum mothers,” Figueiredo told us. “Preterm birth is an important global public health issue, and the influence of preterm birth on maternal mental health was an area of interest to me.”
Researchers identified all the studies published in the last decade on the topic. They included 26 studies in their systematic review and performed qualitative and quantitative analyses in order to test their hypothesis.
Though their study provided evidence of higher risks for postpartum depression among mothers of preterm infants, especially in the early postpartum period., they found a great heterogeneity among the studies in this field, and the discrepancies of methodological approaches seemed to impact on the results.
“We highlight that most of the studies did not consider an integrative approach of postpartum depression, considering emotional, environmental and biological variables,” Figueiredo told us. “Besides, most of the studies did not take into account the role of important confounding variables in their analytical models, such as depression during pregnancy or history of depression.”
Thus, Figueiredo told us, future studies with an integrative approach of postpartum depression and more robust analytical models are needed to provide consistent evidence of the association between preterm birth and postpartum depression.
“We were not surprised with the results themselves, but some aspects of our findings called our attention, such as the inclusion of large samples,” Figueiredo told us. “The studies in this field in the last decade analyzed larger samples, in some cases, barely the whole population of the country. Our systematic review analyzed 26 studies that, taken as whole, assessed 2,474,140 women.”
Another aspect that caught researchers’ attention was that the assessment time-point seemed to play an important role in the association of preterm birth and postpartum depression.
“The evidence of this association is stronger when mothers are assessed in the early postpartum period,” Figueiredo told us. “When considering only the studies that assessed women after the sixth month after delivery (up to one year), results were not conclusive.”
Patricia Tomasi is a mom, maternal mental health advocate, journalist, and speaker. She writes regularly for the Huffington Post Canada, focusing primarily on maternal mental health after suffering from severe postpartum anxiety twice. You can find her Huffington Post biography here. Patricia is also a Patient Expert Advisor for the North American-based, Maternal Mental Health Research Collective and is the founder of the online peer support group - Facebook Postpartum Depression & Anxiety Support Group - with over 1500 members worldwide. Blog: www.patriciatomasiblog.wordpress.com