TGFBR1 and female infertility: The presence of degenerating oocytes/embryos in the oviductal diverticula but absence of blastocysts in the uteri (3.5 dpc) of the Tgfbr1 cKO mice strongly indicate that development of oviductal diverticula is sufficient to cause female infertility in the Tgfbr1 cKO mice, though it is plausible that disruption of the uterine smooth muscle development might sequentially confound the pregnancy outcome if pregnancy could occur in these mice.