In embryos laid by mothers homozygous for cfo, fewer than 10% of embryos develop normally to the blastoderm stage. The majority of pre-blastoderm embryos are arrested at nuclear cycles 1-7 in a mitotic like state, with large barrel-shaped spindles surrounding clusters of mitotic chromatin. Almost all of these spindles are devoid of centrosomes, and free centrosomes are usually randomly distributed throughout the cytoplasm. Most of the chromosomes on these spindles are in an anaphase like state, with sister chromatids separated to some extent. Centrosomes apparently drop off causing cell cycle arrest.

2-3% of embryos laid by homozygous mothers hatch as larvae, No cfo¹/Df(3L)AC1 survive.