Accessing National ART Surveillance Data

The use of assisted reproductive technology (ART) in the United States has doubled during the past decade. Yet there are gaps in understanding the scope and outcomes of ART treatment as well as the public health burden of infertility. The National ART Surveillance System (NASS) is a Web-based reporting system that collects information on all ART cycles started in the United States. The data collected in NASS include patient characteristics, ART procedure information, and treatment outcomes that can be used to answer important research questions about using ART. To promote research on trends and outcomes of ART, CDC established a way that researchers outside of CDC can securely access limited, de-identified NASS datasets to conduct analyses.


ART surveillance data are sensitive because they contain personal medical information about both the women undergoing ART and the infants born after ART. These data are protected by the Assurance of Confidentiality under the Public Health Act Section 308(d). Although the data do not contain any primary identifiers, such as names or social security numbers, other indirect identifiers are available in the dataset. As a result of confidentiality restrictions resulting from the sensitive and potentially identifying nature of the data, CDC can provide only restricted access to limited data files.

Research Data Center

CDC’s Research Data Center (RDC), housed within the National Center for Health Statistics (NCHS), allows researchers to analyze restricted data in a secure environment. The remote access system at RDC provides a way for analysis that protects the privacy and confidentiality of the data collected, as required under the Assurance of Confidentiality.

The RDC will host limited, de-identified NASS datasets for cycles initiated during or after 2004 and provide remote access to specific programmers after project proposals for data use have been approved. Output released to the researcher via remote access will suppress all data points for which there are only one to four observations, and additional cells that could reveal the content of the suppressed cells (complementary suppression).

Proposal Process

Researchers interested in accessing NASS data are required to submit a proposal to CDC for review and approval. More detailed information for proposal development can be found in the NASS Research Handbook for External Data Analysis and the NASS Data Dictionary. These documents are described below. Both are available upon request by e-mailing In your request, please include complete contact information and indicate which document you are requesting.

  • The NASS Research Handbook for External Data Analysis includes a description of the dataset, information on how the data are accessed, and the project proposal form.
  • The NASS External Data Dictionary includes detailed information on all variables available through the RDC.

Overview of the proposal process:

  1. The researcher submits a complete project proposal form to CDC’s Division of Reproductive Health via e-mail. The proposal will be screened for completeness and consistency with the available data. The initial screening will take approximately 2 weeks.
  2. If approved, CDC will forward the proposal to the NASS Research Review Committee (NRRC) that comprises five members with extensive knowledge of ART and experience in scientific research, including at least one physician currently practicing in the field of ART and two representatives from the Division of Reproductive Health. The NRRC will evaluate the scientific merit of the proposed research, appropriateness of the methodology, and potential overlap with planned or ongoing projects. The NRRC review will take approximately 4 weeks.
  3. CDC will send proposals approved by the NRRC to the RDC Review Committee for additional confidentiality review.
  4. If the proposal is approved by the NRRC and the RDC, the researcher and all co-investigators will be required to fill out and submit data use agreements.
  5. After submitting these agreements to CDC and RDC, the researcher and a designated programmer (if needed) will be given remote access through the RDC to project-specific datasets for conducting research.
  6. The researcher must submit a progress report to the NRRC on the status of the project 1 year after RDC access is granted.

For more information, please e-mail

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