Catherine Linstrum, who co-wrote Cristian Nemescu's Un Certain Regard winner California Dreamin', is now working on a new script entitled Perish with her artist husband David-John Newman.
Linstrum, based in South Wales, has financial backing from the Film Agency For Wales.
Perish is about a young couple who lose their four-year-old son and then find out their fertility clinic has cleared the conception of his unborn twin sister.
Linstrum previously wrote Dreaming Of Joseph Lees and and has written and directed two shorts, The Boy With The Blue Eyes and The Black Dog.
Newman will collaborate on the script as well as producing video and photographic work to be featured in the film, as the central character is a visual artist working on an exhibition.
'The notion of an unborn child held on ice and waiting to be born struck us as having huge potential for a rich and chilling drama centred on the highly emotive and contemporary subject of infertility and IVF,' Linstrum said.