"Shifting sands in cystic fibrosis": impacts of CFTR modulators on reproductive health in people with cystic fibrosis and challenges related to in utero exposure.

Introduction: Mutation-specific disease modifying drugs such as the triple combination Elexacaftor/Tezacaftor/Ivacaftor (ETI), are associated with significant improvements in physical health. Reproductive health and a pursuit of parenthood are of increased relevance; a dramatic increase in childbirth rates for females with CF has already been observed.

Areas covered: Fertility in males and females with CF, and any subsequent impact of CFTR modulator therapy, is reviewed. The potential impacts of maternal use of CFTR modulator drugs on offspring health are considered, as constituent components have been found in fetal circulation in animals and humans, and the implications for maternal continuation or cessation of treatment. Clinical data are reassuring, although cases of lens opacities, and missed CF diagnoses due to false negative newborn screening results have been reported.

Expert opinion: More research and high-quality evidence are needed to characterize maternal, fetal and long-term offspring outcomes following CFTR modulator therapy use during pregnancy and breastfeeding. There is a potential therapeutic impact of targeting CFTR-related organ dysfunction in CF-fetuses via maternal-administration of CFTR modulators. Additionally, any consequences of CFTR-modulation in heterozygote carrier infant warrants urgent and collective consensus regarding ethical and clinical research programs to evaluate this discrete population.