Relinquishing a child has had lifelong consequences for women and for adoptees. This article explores a little-discussed aspect—secondary infertility, birth mothers who did not have other children. To my knowledge, this is the first study to research the incidence of secondary infertility and its impact on the women concerned. I discovered that between 13–20% of birth mothers do not go on to have other children. For a few, this is a conscious decision; however, for the majority there was either no known reason for infertility or their life circumstances foisted it on them, i.e., lack of suitable partner. Relinquishing their child has meant losing their only opportunity to parent a birth child, and that has bought tremendous anguish. Women considering relinquishing a child need to be made aware that secondary infertility is a real and present possibility.