California's Proposition 71, designed to fund $3 billions in stem cell research, prohibits paying women to be egg donors, the San Diego Union-Tribune said Monday. The human eggs, however, are needed in order to conduct the research.

"The people of California passed Proposition 71 to fund billions of dollars worth of stem cell research including (therapeutic cloning) and then the legislators and leaders of the stem cell institute put guidelines in place that greatly hamper, or virtually eliminate, the possibility of this being successful," Samuel Wood, who founded the biotechnology firm Stemagen, told the newspaper.

The newspaper said Britain was able to overcome a shortage of eggs by allowing women to receive in vitro fertilization for half price if they agreed to give half of their eggs to research.