Infertility and abnormal cervical mucus in two sisters who are compound heterozygotes for the cystic fibrosis (CF) ΔF508 and R117H/7T mutations

Objective: To describe two cases of infertile sisters who are compound heterozygote carriers of the cystic fibrosis (CF) ΔF508 and R117H/7T mutations and who were found to have significantly abnormal cervical mucus. Design: Case reports and review of literature. Setting: Infertility practice based in an academic medical center. Patient(s): Two sisters (ages 34 and 42), compound heterozygote carriers of CF mutations, who presented with involuntary infertility. Intervention(s): The partners of both patients tested negative for CF. The evaluation of both sisters did not indicate other causes of infertility aside from advanced maternal age in the 42-year-old patient. Both sisters underwent natural-cycle intrauterine insemination. Main Outcome Measure(s): Pregnancy conception. Result(s): The 34-year-old patient has subsequently conceived twice through natural-cycle inseminations. Conclusion(s): This is the first reported case of infertility due to a cervical mucus factor in a patient who is a compound heterozygote of the ΔF508 and R117H/7T mutations. This case is important not only because of the distinct phenotypic abnormality seen with specific CF mutations but also because of the associated genotype.