It was a miracle and this is trying making a case based on non-miraculous, ‘natural’ mechanisms. An attempt at an explanation sure, but not knowledge one can infer from the Bible. Male is a phenotype, not a genotype. The available scenarios related to such a miracle are potentially vast. Why presume ‘natural’ mechanisms?
Odd… Here I am, someone largely unsympathetic to ID, explaining an instance where science can provide no explanation and thus is silent, to someone from the DI, who suggests scientific explanations for a miracle.