Whereas the lack of a child brings shame upon Anna and Joachim, the converse holds true for Mary: the existence of an unborn in the womb of a woman who is supposed to be a virgin causes great scandal.
2009, Catherine Playoust, Ellen Bradshaw Aitken, “The Leaping Child: Imagining the Unborn in Early Christian Literature”, in Vanessa R. Sasson, Jane Marie Law, editors, Imagining the Fetus: The Unborn in Myth, Religion, and Culture, Oxford University Press, page 176