Stepping onto dangerous theological ground, it seems that if human embryos consisting of one hundred cells or less are the moral equivalents of a normal adult, then religious believers must accept that such embryos share all of the attributes of a human being, including the possession of an immortal soul. So even if we generously exclude all of the naturally conceived abnormal embryospresuming, for the sake of theological argument, that imperfections in their gene expression have somehow blocked the installation of a soulthat would still mean that perhaps 40 percent of all the residents of Heaven were never born, never developed brains, and never had thoughts, emotions, experiences, hopes, dreams, or desires.
That's assuming that they go to Heaven; according to Dante, the unbaptised would go to Limbo, the uppermost circle of Hell, where they would mix with virtuous heathens.
(This conjures up all sorts of surreal questions and fictional scenarios, such as what relations between the two groups in Heavenly society. Would the embryos see themselves as purer than or superior to than the immigrants, sullied by the sinful world? Would the born-and-died be marginalised as second-class citizens, or form a culture of resentment of the establishment? Presumably Heaven is defined as an enlightened autocracy, ruled by an all-wise and benevolent God with vast bureaucracies and military orders of angels, who would keep the peace somehow. Though, if we transpose this to Philip Pullman's Republic of Heaven, would the Pure and the Dead have separate political parties bitterly contesting their interests in the Heavenly Parliament; or perhaps Heaven would be a fascist state run by the Pure?)