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Z-Scores for Assessing Ovarian Reserve in Young Patients Undergoing Fertility Preservation
Published on: October 25, 2024
Age-Specific Gonadotoxic Alkylating-Agent Exposure in Pediatric and Reproductive-Age Females: A Claims-Based Study
Kentaro Taniguchi1, Mizuki Ohashi1, Yuji Tanaka1
1Department of Obstetrics and Gynaecology Shiga University of Medical Science Otsu Shiga Japan.
Reproductive Medicine and Biology
|August 4, 2026
Summary
The cyclophosphamide equivalent dose (CED) framework better captures alkylating-agent exposure in pediatric patients but has limitations for reproductive-age females, highlighting the need for refined fertility preservation assessments.
Area of Science:
- Oncology
- Pharmacology
- Reproductive Medicine
Background:
- Gonadotoxic alkylating agents are used in cancer treatment.
- Accurate assessment of exposure is crucial for fertility preservation counseling.
- The cyclophosphamide equivalent dose (CED) framework standardizes exposure measurement.
Purpose of the Study:
- To describe age-specific patterns of gonadotoxic alkylating-agent exposure.
- To evaluate the cyclophosphamide equivalent dose (CED) framework's ability to capture real-world exposure relevant to fertility preservation in females aged 0-43 years.
Main Methods:
- A descriptive study utilizing a Japanese claims database.
- Patients categorized into pediatric (<15 years) and reproductive-age (15-43 years) cohorts.
- Twelve alkylating agents were assessed; six were converted to CED.
Main Results:
- 0.04% of pediatric and 0.16% of reproductive-age females were exposed to alkylating agents.
- Summed CED identified intermediate-risk exposure in 33% of exposed pediatric and 14% of exposed reproductive-age patients.
- Agents not included in CED calculations represented 8.7% of prescriptions, primarily in reproductive-age females.
Conclusions:
- CED captures alkylating-agent exposure differently across age groups.
- Summed CED improved exposure information capture in pediatric patients.
- Limitations in CED conversion coefficients for certain agents impact exposure assessment in reproductive-age females, suggesting refinement is needed for fertility preservation evaluations.
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