An observational study in Sickle Cell Anemia, sponsored by Children's Hospital Medical Center, Cincinnati. Recruiting at 3 sites in 3 countries. Open to participants aged 8 Years and older. Per ClinicalTrials.gov, last updated 2026-02-04.
Sponsored by Children's Hospital Medical Center, Cincinnati · Observational
The SAFE study is a long-term research project that watches people with sickle cell anemia (SCA) over time. The main goal is to see how a medicine called hydroxyurea affects their growth, puberty, and ability to have children. A second goal is to see how hydroxyurea affects pregnancy outcomes, by comparing people who take the medicine to those who don't.
Hydroxyurea is a medicine that helps people with sickle cell anemia (SCA), a serious blood disease. It works by increasing a special type of hemoglobin (called fetal hemoglobin) that helps prevent sickle cell problems.
This medicine is especially helpful in places where it's hard to get safe blood transfusions. Studies from around the world have shown that hydroxyurea is safe and can reduce serious health problems caused by SCA (like pain, strokes, and lung issues). It can also help people with SCA live longer, healthier lives.
However, the investigators still don't know everything about how hydroxyurea affects long-term growth, puberty, fertility, or pregnancy; especially in areas with fewer medical resources.
To learn more, researchers are planning a large international study. They will follow people with SCA over time to see how hydroxyurea affects their development, ability to have children, and pregnancy outcomes. Participants will visit the clinic every few months for check-ups, blood tests, and other health assessments. Girls who have started their periods will take pregnancy tests every six months, and boys may be asked to provide a semen sample if they agree. Everyone will also answer questions about their health and fertility regularly.
1,134 studies on the registry are indexed under Anemia, Sickle Cell; 238 are open to participants now.
This study's planned enrollment of 250 is above the median of 100 across 296 observational studies indexed under Anemia, Sickle Cell.
Browse Anemia, Sickle Cell studies →Children's Hospital Medical Center, Cincinnati is the lead sponsor of 673 studies on the registry; 130 are open to participants now.
Of its 57 completed or terminated interventional studies of FDA-regulated products, 31 (54%) have results posted.
Counted across the registry records on this site, refreshed daily.
People with sickle cell anemia who are at least 8 years old and seen in Jamaica and Dominican Republic.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Those with sickle cell anemia (SCA).
Clinical Outcomes
The number of people who experience serious health events like pregnancy, stroke, cancer, or death.
Time frame: From enrollment up to 10 years after enrollment.
Female Reproductive Potential and Outcomes
Female fertility potential will be measured using serum anti-mullerian hormone (physiologic parameter)
Time frame: From enrollment up to 10 years after enrollment.
Female Reproductive Potential and Outcomes
Female ability to conceive will be assessed using incidence of pregnancy (questionnaire)
Time frame: From enrollment up to 10 years after enrollment.
Female Reproductive Potential and Outcomes
Outcomes of pregnancy will be categorized as either abortion or live birth (questionnaire)
Time frame: From enrollment up to 10 years after enrollment.
Female Reproductive Potential and Outcomes
Mode of delivery will be categorized as vaginal or c-section (questionnaire)
Time frame: From enrollment up to 10 years after enrollment.
Female Reproductive Potential and Outcomes
Prematurity of infant will be categorized as premature or full term (questionnaire)
Time frame: From enrollment up to 10 years after enrollment.
Female Reproductive Potential and Outcomes
Weight of infant will be categorized as normal birth weight or low birth weight (questionnaire)
Time frame: From enrollment up to 10 years after enrollment.
Male Reproductive Potential and Outcomes
Male fertility potential will be measured using sperm analysis (physiologic parameter)
Time frame: From enrollment up to 10 years after enrollment.
Male Reproductive Potential and Outcomes
Male ability to conceive will be assessed using incidence of impregnated partner (questionnaire)
Time frame: From enrollment up to 10 years after enrollment.
Male Reproductive Potential and Outcomes
Outcomes of pregnancy will be categorized as either abortion or live birth (questionnaire)
Time frame: From enrollment up to 10 years after enrollment.
Male Reproductive Potential and Outcomes
Mode of delivery will be categorized as vaginal or c-section (questionnaire)
Time frame: From enrollment up to 10 years after enrollment.
Male Reproductive Potential and Outcomes
Prematurity of infant will be categorized as premature or full term (questionnaire)
Time frame: From enrollment up to 10 years after enrollment.
Male Reproductive Potential and Outcomes
Weight of infant will be categorized as normal birth weight or low birth weight (questionnaire)
Time frame: From enrollment up to 10 years after enrollment.
Plan to share: No — Study data will be collected and managed using REDCap™ electronic data capture tools. REDCap™ is a secure, web-based application designed to support data capture for research studies, providing: 1) an intuitive interface for validated data entry; 2) audit trails for tracking data manipulation and export procedures; 3) automated export procedures for seamless data downloads to common statistical packages; and 4) procedures for importing data from external sources. The REDCap™ system is available for use through institutions participating in the REDCap™ consortium. Cincinnati Children's Hospital Medical Center serves as the home institution to allow the REDCap™ system for de-identified data collection in the SAFE study.
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