text: In 1977 the US Federal Drug Administration published a clinical trial guideline that excluded women of "childbearing potential" from the early phases of most clinical trials, which in practice led to their exclusion from later trial phases as well. This 1977 FDA guideline was implemented in response to a protectionist climate caused by the thalidomide tragedy. In the 1980s, a US task force on womens health concluded that a lack of womens health research (in part due to the FDA guideline) had compromised the amount and quality of information available about diseases and treatments affecting women. This led to the National Institute of Health policy that women should, when beneficial, be included in clinical trials.