Infants' Health Affected by Mothers Prenatal Anxiety

Reference

Beijers R, Jansen J, Riksen-Walraven M, de Weerth C. Maternal prenatal anxiety and stress predict infant illnesses and health complaints. Pediatrics. 2010;126(2):e401-409.

Design

Prospective cohort study.

Participants

174 mothers with normal pregnancies and term deliveries in the Netherlands completed questionnaires during their third trimester to quantify stress and anxiety and provided saliva samples to assess cortisol levels. Subjects were then interviewed on a monthly basis for the infants’ first year in order to determine the frequency of illness and antibiotic use.

Key Findings

Adjustments were made for confounding factors including, but not limited to, maternal smoking and alcohol use, duration of breastfeeding, and day-care attendance. The results suggest that maternal stress and anxiety are positive predictors of infant illness and antibiotic use in the first year of life. In particular, the findings show an association between increased maternal stress and anxiety and respiratory, skin, and general illnesses and antibiotic use, but not digestive illness. There was also a correlation between higher evening cortisol levels or flattened diurnal cortisol rhythms and increased incidence of infant illnesses.

Practice Implications

A number of studies have previously established that maternal stress has a negative impact on infant temperament and cognitive development; however this is the first study to explore the effect of prenatal maternal stress on the incidence of infant illness.^1,2,3 Evidence from both this and previous studies suggests that it is during the third trimester that the effects of elevated cortisol and maternal stress and anxiety are most influential on postnatal outcomes.⁴ In fact, it was reported that women exposed to natural disasters (such as hurricanes Andrew and Katrina in the United States) during second and third trimesters had an increased risk of fetal distress as compared to those exposed during the first trimester.^5,6

Stress is known to activate beta-adrenergic receptors, which may influence different aspects of cognitive function.⁷ A 2008 study by Connors et al suggests that over-stimulation of the beta-adrenergic receptors from stress or drugs such as terbutaline (administered to stop preterm labor) are linked to an increased risk for autism.^8,9 By establishing a link to increased infant illnesses, this study may also point to a link between the influence of maternal stress on the intrauterine environment and the immune dysfunction in neurodevelopmental disorders such as autism.¹⁰

Factors including social and cultural norms, social support and fathers involvement, guidance and support from healthcare providers, education, and work environment contribute to a womans decision to breastfeed.

Factors including social and cultural norms, social support and father’s involvement, guidance and support from healthcare providers, education, and work environment contribute to a woman’s decision to breastfeed. It would then seem reasonable that these factors influence maternal stress and anxiety as well.^11,12,13 While the investigators did adjust for breastfeeding, it should still be considered that mothers who report higher levels of prenatal stress and anxiety may also be those less likely to breastfeed. The positive impact of breastfeeding on the developing immune system is very well established, and its protective effects should not be discounted; it may not reduce frequency of illness, but it can potentially reduce the severity.¹⁴ Breastfeeding should continue to be encouraged, particularly in mothers with higher levels of stress and anxiety.

This study reinforces the importance of addressing stress and anxiety in pregnant patients. Both the self-assessment questionnaires and cortisol levels were shown to be predictive of infant illness and antibiotic use. Thus, it is certainly worthwhile to consider both parameters as tools to monitor this population in practice, potentially saving time during the interview to assess the mother’s stress level and support resources. Early recognition and intervention on the part of the practitioner may very well serve to reduce maternal stress and anxiety, thereby reducing infant illness and antibiotic use.

Further investigation is certainly warranted to both confirm the findings of this particular study, as well as to determine the therapeutic effects of how decreasing maternal stress and anxiety in the third trimester can impact infant health.