FRIDAY, Dec. 14, 2018 (HealthDay News) -- Parental subfertility is associated with an increased asthma risk among offspring, according to a study published online Dec. 4 in Thorax.
Maria Christine Magnus, Ph.D., from the Norwegian Institute of Public Health in Oslo, and colleagues clarified the impact of parental subfertility on the correlation between assisted reproductive technologies (ART) and childhood asthma. Data were included from national Norwegian health registries (474,402 participants) and the Norwegian Mother and Child Cohort Study (MoBa; 75,797 participants).
The researchers found that ART offspring had greater asthma risk in the registry-based cohort and in MoBa (adjusted relative risks [aRRs], 1.2 [95 percent confidence interval (CI), 1.09 to 1.32] and 1.42 [95 percent CI, 1.14 to 1.76], respectively). Similar associations were seen in the sibling analysis. When ART offspring were compared to spontaneously conceived offspring with time to conception >12 months, the elevated asthma risk was attenuated (aRR, 1.22; 95 percent CI, 0.95 to 1.57). Maternal history of early miscarriages (≤12 weeks) was associated with an increase in asthma risk, with aRRs of 1.07 (95 percent CI, 1.03 to 1.11), 1.18 (95 percent CI, 1.1 to 1.26), and 1.24 (95 percent CI, 1.12 to 1.37) for one, two, and three or more, respectively.
"The incremental increased risk of asthma according to maternal history of early miscarriages lends some support to the notion that there might be common mechanisms underlying parental subfertility and recurrent miscarriages that play a role in offspring asthma pathogenesis," the authors write.