My girlfriend and I are acquainted with no fewer than two-dozen forty-something women, all of them successful, well-educated, charming ladies. They are librarians, museum curators, teachers and the like. Besides these similarities, they hold two more characteristics in common. They are all single and childless.

Any of these women would have made fine partners and wonderful mothers. They could have borne bright, responsible, successful children who could have contributed greatly to society. But for various reasons it wasn’t to be.

Most spent their twenties working on themselves, attending graduate school and later focusing on their careers. By their thirties, they found themselves in long-term relationships that ended after a half dozen or so years. Their stories are strikingly familiar.