Caffeine consumption during pregnancy tied to shorter stature in children

Children born to mothers with increased intake of caffeine and paraxanthine during pregnancy are likely to have shorter stature, which persists up to 8 years of age, according to a study.

The study used data from two pregnancy cohorts with longitudinal follow-up and distinct patterns of low and high caffeine consumption: the Environmental Influences on Child Health Outcomes cohort (ECHO-FGS; 10 sites, 2009-2013) and the Collaborative Perinatal Project (CPP; 12 sites, 1959-1965). The children were followed up through 8 years of age in both cohorts.

Intake concentrations of caffeine and its primary metabolite, paraxanthine, were measured from plasma (ECHO-FGS) and serum (CPP) collected in the first trimester. Cut points for analyses were defined by quartiles in ECHO-FGS and by quintiles in CPP.

Researchers determined child z scores for body mass index, weight, and height, as well as fat mass index and percentage and obesity risk measured at 1 time between age 4 and 8 years in ECHO-FGS. They conducted a secondary analysis using the CPP cohort, with child z scores and obesity risk longitudinally evaluated through age 8 years

A total of 788 children (mean age 6.8 years, 52.2 percent boys) and 1,622 children (49.7 percent boys) were included in the ECHO-FGS and CPP cohorts, respectively. Median maternal caffeine intake levels were <50 mg/d in ECHO-FGS and two cups/d in CPP.

In ECHO-FGS, children born to women in the fourth vs first quartile of plasma caffeine concentrations had lower height z scores (β, −0.21), although the differences in weight z scores were only observed in the third quartile (β, −0.27).

In CPP, on the other hand, children born to women in the highest caffeine quintile group had lower height z scores than their peers from the lowest group, with the difference seen beginning at age 4 years the gap widening with each successive year of age (β, −0.16 at 4 years; β, −0.37 at 8 years). There were slight reductions in weight at ages 5–8 years for children in the third vs first caffeine quintile (β, −0.16 to −0.22).

Similar results were obtained for paraxanthine concentrations in both cohorts.