Can zolpidem be used by a woman who is breastfeeding her baby?

One of my patients had previously taken zolpidem (Ambien®) for sleep in a clinically appropriate manner and with good benefit. When she decided to attempt to become pregnant, the zolpidem was stopped. Throughout the pregnancy, she struggled with persistent problems with clinically-significant insomnia despite all kinds of non-pharmacological interventions and the use of an antihistamine….