Study leader Dr Qiuying Yang, from the University of Ottawa, said the study was the largest to date and showed an important link between caesareans and subsequent pregnancy complications.

BBC: NEWS | Health | Caesarean link to placenta risk

"These results open the potential for visibly transparent polymer solar cells as add-on components of portable electronics, smart windows and building-integrated photovoltaics and in other applications, " said study leader Yang Yang, a UCLA professor of materials science and engineering, who also is director of the Nano Renewable Energy Center at California NanoSystems Institute (CNSI).

ENGADGET: UCLA creates transparent solar cell, dreams of current generating windows