Project Ice Storm

Ice Storm map

Current Project underway:

Project Ice Storm: Continuing Effects of Prenatal Stress on Children's Physical, Cognitive and Behavioural Development in Adolescence

S. King, D.P. Laplante, A. Brunet, K. N. Dancause, N. Grizenko, R. Joober and N. Schmitz

What is Project Ice Storm?

Project Ice Storm was designed to study the effects of in utero exposure to varying levels of prenatal maternal stress (PNMS), resulting from an independent stressor on the children's development from birth through childhood. In January 1998, the Quebec Ice Storm left millions of people without electricity for up to 40 days. In Project Ice Storm we were able to separate the "objective" stressors (days without power) from the "subjective" reactions (post-traumatic stress symptoms) and physiological reactions (cortisol over 24 hours), and maternal personality factors of 178 pregnant women exposed to the disaster. Child follow-ups at ages 6 months, and 2, 4, 5.5 and 6.5 years show significant effects of objective and subjective PNMS on temperament, parent- and teacher-rated behaviour problems, motor development, physical development, and IQ, attention, and language development. The majority of these effects persist at our most recent assessments.

What is our goal?

The goal of the current study is to understand the long-term effects of the prenatal exposure to stress on the physical growth and functioning, cognitive development, and behaviour of the Project Ice Storm children by studying developmental trajectories through age 13.

Who is involved?

Nearly 100 families have continued to participate in Project Ice Storm. This study is composed of 4 assessment periods: i) Comprehensive home visits when the children are 8.5 and 11.5 years old to determine the long-term effects of PNMS on the children's physical, cognitive, and behavioural development; ii) Questionnaire survey of grade 3, 4 and 5 teachers to assess behavioural and attention problems at school at 8, 9 and 10 years of age; and iii) A postal questionnaire to obtain parental ratings of their children's behavioural and attention problems at home at 9.5 years.

Next Steps

There are several studies on associations between maternal pregnancy anxiety and outcomes in their children. However, these efforts cannot determine how much of the effects are due to genetic transmission of anxiety, effects of stress hormones on the uterine environment, and maternal modelling of anxiety after birth. Project Ice Storm is the only project in the world that (1) studies the effects of an independent stressor; (2) and is, thus, able to separate effects due to objective exposure to the event from the mother's subjective reaction to it, while controlling for trait levels of anxiety and depression; (3) is studying effects prospectively since shortly after a stressful event and while most of the sample was still pregnant; (4) and has a prospective sample of greater than 100 families. To date, we have obtained significant effects of prenatal maternal stress in every area of development that we have examined. Extrapolating our findings to more severe events, such as war and other forms of natural and man-made disaster, the strong effects we find may possibly be multiplied in other contexts.