Abstract
This month's LactMed column features a comprehensive summary by our Pharmacology Editor Dr Philip Anderson regarding the treatment options of treating maternal postpartum sleep disorders, particularly insomnia, in breastfeeding mothers. Although most caretakers would agree that nonpharmacological strategies are the preferred route to be taken, Dr Anderson acknowledges that at time these techniques are clearly unsatisfactory. As such, he reviewed the available drug options with a focus and emphasis which drugs potentially alter maternal behavior, alertness, and thus interfere with breastfeeding per se.
In addition, he addressed the issue which medication has the lowest risk in affecting infant behavior alertness and ultimately negatively impacting on the infant's capacity to latch, suck, and sustain breastfeeding. No less so Dr Anderson discusses the issue of the possible increased risk of sudden infant death syndrome in infants who are nursing from mothers who are ingesting sedative or antidepressant drugs as treatment for insomnia and the dilemma of the use of these drugs when advocating maternal infant co-sleeping.
The complexity and challenge in analyzing the relationship of maternal sleep patterns and breastfeeding can be appreciated by reviewing the existing literature regarding the interaction of the two variables. Doan et al. 1 in 2007 documented that breastfeeding mothers, contrary to “intuitive expectations,” slept more (some 40–45 minutes) than mothers who formula bottle fed their infants. Most interesting she also found that fathers of breastfed infants slept longer than the fathers of formula-fed fathers. 2 This positive effect of exclusive breastfeeding on mothers' sleep duration was most evident in first-time mothers.
The importance of breastfeeding in modulating maternal mood and ultimately sleep behavior was emphasized by Stuebe et al. 3 in her study of >200 maternal infant dyads. Their longitudinal study documented that symptom of depression, eating disorders, and poor sleep quality during pregnancy were associated with earlier postpartum introduction of formula and less exclusive breastfeeding. They concluded that their data supported the conclusion that pre-existing maternal sleep problems are a risk for poorer breastfeeding outcomes and not that poor breasting causes sleep disruption and mood disorders.
Alimi et al. 4 recently published a comprehensive review and metanalysis of the reports of an association of breastfeeding and a reduced risk for postpartum depression. They noted that women who did not exclusively breastfeed had an 89% higher odds increased risk of developing postpartum depression, implying that breastfeeding is to a degree a preventive if not a mitigating procedure
This proverbial chicken and egg dilemma (Which came first? The depression and sleep disorders or the decreased frequency and/or exclusivity of breastfeeding) can be resolved by conceptualizing the relationship as a bidirectional one and not a circular phenomenon. As noted, prenatal mood and sleep disorders correlate with lower self-efficacy and lower breastfeeding rates, Clearly it is the psychodynamics of the mother and not the mechanics of breastfeeding that is the critical variable.
Such prenatal symptoms of depression are associated with lower oxytocin levels. Oxytocin a neuropeptide hormone that has anxiolytic and antidepressant effects, and has positive effects on social affiliation and behavior, particularly in parenting and attachment relationships.5,6 The process of breastfeeding itself is a stimulus that results in an increased maternal level of oxytocin thus potentially blunting the expression of depression and its associated sleep disorders. Oxytocin enhances maternal–infant attachment, further mitigating any tendency to postpartum depression.
Given the aforementioned, it is clear that we should heed Dr Anderson's recommendations, that is, to use if possible nonpharmacological agents in treating the nursing mothers' insomnia. In those cases of therapeutic failure one should choose wisely from his long list of drugs that were reviewed and analyzed. In addition, one should advocate and support exclusive breastfeeding in all mothers so as to maximize maternal oxytocin levels and better sleep patterns, which will, in turn, enhance more positive moods and behaviors and mitigate any tendency to depression.