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Continuation of Follow-up of DES-Exposed Cohorts
NCT00340600 · View on ClinicalTrials.gov ↗
Study Summary
Diethylstilbestrol (DES), a drug first synthesized in 1938, was administered to several million pregnant women in the U.S. and Europe for the prevention of spontaneous abortion and premature delivery. In 1971, Herbst reported a strong association between DES use in pregnancy and the occurrence of vaginal clear cell adenocarcinoma (CCA) in exposed female offspring. Animal models have demonstrated a range of DES effects on offspring exposed in utero, including reproductive dysfunction, immune system changes, behavioral and sexual abnormalities, and increases in various reproductive cancers in males and females. In the mid-1970's, several separate cohorts of DES-exposed daughters and unexposed comparison groups were followed for the occurrence of cancer, precursor lesions, and reproductive effects, but systematic follow-up of these cohorts had ceased by 1990. In 1992, Congress passed a bill (H;.R. 4178) mandating the continued follow-up of DES-exposed cohorts. The National Cancer Institute, in collaboration with five field centers, reassembled previously studied cohorts of DES-exposed and unexposed mothers, daughters and sons, and identified subjects with documented exposure status who had not been studied previously, through familial links within the cohorts. Standardized baseline questionnaires were mailed to cohort members to ascertain the risk of cancer and other disorders. Pathology reports were collected for reported cancers and preneoplastic conditions. Two separate rounds of follow up have been conducted and a third is almost complete. Patients from the Registry for Research on Hormonal Transplacental Carcinogenesis (the Registry) will be added to the follow-up effort in the third phase. The purpose of this study is to continue the follow-up, by means of mail questionnaires and medical record collection, which was begun during the first phase of the study. Concern has arisen that DES-exposed daughters may be at higher risk of breast cancer. Exposure to high lev
Conditions Studied
Study Locations (1)
Massachusetts
- Boston University School of Public Health — Boston
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 10,805 participants |
| Start Date | 1998-03-18 |
| Est. Completion | 2020-11-13 |
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Full Details on ClinicalTrials.gov ↗What the Registry Record Tells You About NCT00340600
The ClinicalTrials.gov registry entry for NCT00340600 describes a study currently listed as completed. It is categorized as an unspecified phase, which is the standard way researchers label where a study sits along the investigational pathway from early safety work through later efficacy and post-marketing evaluation. The registered enrollment target is 10,805 participants, a figure that helps gauge the scale of data the investigators plan to collect. The listed sponsor is National Cancer Institute (NCI), which has 2,390 total studies on file at ClinicalTrials.gov, and sponsors are the parties responsible for study design, oversight, and regulatory filings.
The record links to 5 conditions, with Breast Cancer appearing as the primary indexed condition, and to 0 interventions. Interventions can include drugs, devices, procedures, behavioral programs, or observational arms, and each is tracked as a separate registry field so that downstream queries can filter accurately. When a trial lists multiple interventions, it usually reflects a multi-arm design or a comparison protocol rather than a single treatment being tested in isolation. The brief summary published in the registry is the clearest source of protocol intent and should be read before drawing conclusions from any sidebar tags.
Geographic footprint matters for practical reasons: NCT00340600 reports 1 study location spanning 1 distinct geographic area — top geographies include Massachusetts. A larger site network tends to correlate with broader recruitment capacity, but it does not imply anything about study quality, and site-level enrollment status can diverge from the overall registry status shown above. Every data point on this page comes from the public ClinicalTrials.gov dataset and is reproduced here for reference only; it is not a medical recommendation, an endorsement of the sponsor, or an invitation to enroll. Verify current status, eligibility criteria, and contact details directly at ClinicalTrials.gov, and discuss any participation decision with your own healthcare provider.
Frequently Asked Questions
What is clinical trial NCT00340600 about?
NCT00340600 is a clinical study titled "Continuation of Follow-up of DES-Exposed Cohorts". Diethylstilbestrol (DES), a drug first synthesized in 1938, was administered to several million pregnant women in the U.S. and Europe for the prevention of spontaneous abortion and premature delivery. In 1971, Herbst reported a strong association between DES use in pregnancy and the occurrence of va...
What is the current status of trial NCT00340600?
This trial is currently completed. The enrollment target is 10,805 participants. The study started on 1998-03-18. Estimated completion is 2020-11-13.
What conditions does trial NCT00340600 study?
This clinical trial studies the following conditions: Breast Cancer, Prostate Cancer, Ovarian Cancer, Endometrial Cancer, Autoimmune Disease. These conditions were identified from the trial registry and reflect the primary focus areas of the research.
Who is sponsoring clinical trial NCT00340600?
This trial is sponsored by National Cancer Institute (NCI), which has 2,390 total clinical trials registered on ClinicalTrials.gov. The sponsor is responsible for the study's design, funding, and regulatory compliance.
Where is trial NCT00340600 being conducted?
This trial has 1 study location across Massachusetts. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.
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