My new book, A Conspiracy of Breath, deals with some very dark subject matter. My heroine, the historical figure Priscilla who is mentioned several times in the Bible in conjunction with her husband Aquila, miscarries her first child. However, even though she did not have a full-term pregnancy, she nonetheless experienced what we would today call post-partum depression.

Though I have not personally experienced that kind of depression, I have seen it in someone I love. It was excruciating to watch. Here is how I described Priscilla and her friend Cordelia in the midst of this mental trial.

It was the nighttime that was worst. Each evening, to Aquila’s bewilderment, I would feel myself begin to splinter like wooden table legs when a wagonload is unloaded onto it. I was defenseless against the inchoate darknesses, the sadnesses, the murky irrationality of fears that seemed to partake of my own flesh and make it their substantial own and that in the night watches gathered into a singularity, a faceless entity of dread.

Once when trimming Aquila’s fingernails, I accidentally drew blood. For the rest of the night I lay and thought of a hundred ways I could injure my own hand.

I began to wonder if I were losing my mind. Then this substance began to come to inhabit daytime hours too, and within days was so constant a companion that I could see the concern in Cordelia’s eyes.

“This is the way of many women after a child,” she told me, “and it will pass.”

But it did not pass. It grew.

“You have not had a child,” I said one day. I knew my words hurt her but I could not stop myself from infecting her with the sickness-dark that was within me. “So how can you assure me, since you have not had a child?”

Her words were quiet and her eyes averted.

“Nor did you experience having a child,” she said, letting her voice linger on what she said. “But you have all the other effects. This is the way of many women, and once you have looked it in the eye, it will begin to leave you.”

But this aspect of woman-ness did not leave at once, or all at once. It became a secret, shared companion to her and to me both, an unwelcome guest for whom we set a place at the table of our conversations and looked in upon at dusk and midnight and acknowledged each dawn.

But with each sunrise its once-irresistible pointing finger began to lose its authority to dominate and direct; and one morning we both knew that it was leaving its garments behind and would visit again, but that it no longer resided with us.

Have you experienced post-partum depression? What were its symptoms for you?