Movement variation in infants born following IVF/ICSI with and without ovarian hyperstimulation

Motor behaviour in infancy is associated with neurological, cognitive, and behavioural function of children born to parents with reduced fertility

AIM

To evaluate the associations between motor development in infancy and developmental outcomes at school age.

METHOD

Participants were 195 children (99 males, 96 females; mean age [SD] 9y 3mo [3mo], range 8y 4mo-10y 11mo) born to couples whose reduced fertility was or was not treated with assisted reproductive technologies. Motor behaviour was assessed at 4, 10, and 18 months with the Infant Motor Profile (IMP). IQ, neurological optimality score (NOS), and behavioural problem scores were measured at 9 years with the Wechsler Abbreviated Scale of Intelligence, minor neurological dysfunction assessment, and the Child Behavior Checklist respectively.

RESULTS

Children with a slow developmental trajectory in the IMP-domain adaptability had an IQ 12.6 points lower (95% confidence interval [CI] 4.7-20.4) and an NOS 3.4 points lower (95% CI 0.7-6.2) at 9 years of age than children with typical adaptability development. Children with a slow developmental trajectory in the IMP-domain performance had an IQ 5.0 points lower (95% CI 0.7-9.3) than children with typical performance development. A non-optimal trajectory in IMP-variation and a fluctuating trajectory in IMP-fluency were associated with higher internalizing scores of 3.6 and 5.8 points respectively, than infants with optimal IMP-domain trajectories.

INTERPRETATION

In relatively low-risk children, motor behaviour in infancy was associated with neurological, cognitive, and behavioural function at school age.

Motor development in infancy is related to cognitive function at 4 years of age

AIM

Evidence is accumulating that motor and cognitive development are interrelated. This study investigates associations between motor development in infancy and cognitive function at 4 years of age.

METHOD

This study is part of the Groningen prospective cohort study on the development of children born after assisted reproductive techniques such as in vitro fertilization. The study group consisted of 223 children (119 males, 104 females) born to subfertile couples (median gestational age 39.6wks, range 30-43wks). Motor behaviour was assessed with the Infant Motor Profile (IMP) at 4 months, 10 months, and 18 months. IQ was evaluated at 4 years with the Kaufman Assessment Battery for Children, Second Edition. Latent class growth modelling was used to analyse relations between IMP and IQ scores.

RESULTS

Infants with low total IMP scores had an IQ that was 8.9 points lower at 4 years than infants with typical IMP scores (95% confidence interval 3.6-14.1). Also, low scores in the domains of variation and performance were associated with a lower IQ at 4 years of age, by 6.1 points and 13.2 points respectively.

INTERPRETATION

Motor development in relatively low-risk infants is associated with cognition at 4 years of age. In particular, low motor variation and performance are associated with a lower IQ at 4 years of age.

WHAT THIS PAPER ADDS

Motor development in infancy is directly related to cognitive function at 4 years of age. This relationship is most pronounced for infant motor variation and performance. The size of the differences in IQ is clinically relevant.

Inter- and Intrarater Reliability of the Infant Motor Profile in 3- to 18-Month-Old Infants

PURPOSE

To investigate inter- and intrarater reliability scoring the Infant Motor Profile (IMP).

METHODS

A total of 20 infants at risk for motor developmental delay were assessed using the IMP. Six infants were born at term (gestational age: 38-42 weeks), and 14 infants were preterm (gestational age: 24-35 weeks). Videos were analyzed twice with an interval of 1 month by 4 assessors after 2 days of IMP training.

RESULTS

Spearman rank scores demonstrated strong interrater and intrarater reliability for total IMP scores (inter: r = 0.80-0.96; intra: r = 0.85-0.97) and the domain of performance (r = 0.95-0.99). Reliability for the domains of variation, variability, and fluency was satisfactory (inter: r = 0.15-0.85; intra: r = 0.30-0.92). The weakest agreement was found in the domain of symmetry (inter: r = 0.20-0.69; intra: r = 0.33-0.65).

CONCLUSION

Therapists naive to the IMP demonstrate good intra and interrater reliability (after 2 days of training) for most domains with the exception of symmetry.