Poor mental health in new parents predicts worse sleep months later

Sleep deprivation and new parenthood go hand in hand, but the relationship between sleep and mental health during this transition is a two-way street. A new study published in Sleep Health shows that parental depression and anxiety symptoms can predict poorer perceived sleep quality months later in both mothers and fathers. The findings reveal that emotional distress may continually degrade a parent’s experience of rest even as an infant grows and begins to sleep through the night.

The transition to parenthood brings profound physiological, psychological, and social adjustments. Up to 70 percent of mothers and 50 percent of fathers experience disturbed sleep during the postpartum period. In addition, depression and anxiety affect up to 20 percent of new mothers and 10 percent of new fathers.

In the general adult population, sleep disturbances and mental health symptoms share a cyclical relationship. Insomnia can trigger depression or anxiety, and those conditions can in turn make it harder to sleep. The perinatal and postpartum periods offer a uniquely vulnerable window for these issues to emerge due to shifting hormones and new psychosocial pressures.

Postpartum sleep disruptions are often prolonged and highly fragmented. They are largely driven by the unpredictable demands of infant feeding and soothing. While prior research has linked early sleep disturbances to worse maternal mood, few researchers have investigated whether parental emotional distress actively predicts later sleep problems.

Most past studies also focused heavily on mothers in the very early postpartum weeks, leaving fathers understudied. Research has also leaned heavily on self-reported sleep measures rather than objective tracking. To address these gaps, researchers led by Avel Horwitz at Ben-Gurion University of the Negev in Israel designed a year-long observational study.

The research team recruited 232 Israeli couples who were expecting a child. The couples joined the study during the third trimester of pregnancy and provided follow-up data at four, eight, and twelve months postpartum. The researchers excluded individuals who were already taking psychiatric or sleep medications prior to pregnancy.

At each of the four time points, parents underwent a one-week sleep assessment. To measure sleep objectively, parents wore actigraphy devices on their non-dominant wrists. Actigraphy is a technique that uses a watch-like motion sensor to track physical movement, allowing researchers to estimate exactly when a person falls asleep and how often they wake up.

Alongside the wrist monitors, parents completed daily sleep diaries for a week. They logged their total hours of rest and rated their subjective sleep quality on a scale from one to ten. Parents also filled out standardized questionnaires to assess the severity of their insomnia, depression, and general anxiety symptoms.

Because the scores for depression and anxiety tracked so closely together, the researchers combined them into a single metric for emotional distress. They then analyzed the data to see how sleep and mental health lined up at each specific time point. They also used advanced statistical models to track how changes in one factor predicted changes in the other over the course of the year.

When looking at the data from the same time points, the researchers found a reliable link between self-reported sleep quality and mental health. Mothers and fathers who rated their sleep poorly in their diaries, or who reported high insomnia symptoms, also exhibited higher levels of depression and anxiety. This pattern held true almost universally across pregnancy and the entire first year postpartum.

The objective actigraphy data showed no such connection. The physical movement data recorded by the wrist monitors did not correlate with the parents’ mental health scores. The researchers suggest that actigraphy might fail to capture certain types of postpartum sleep disruptions, such as a parent lying perfectly still but awake with worry.

It is also highly possible that emotional distress skews a parent’s perception of their own rest. A parent struggling with depression or anxiety might feel that their sleep is much worse than a motion tracker would indicate. By separating the assessments over time, the researchers were able to look beyond this immediate reporting bias to see how symptoms unfolded sequentially.

The statistical models isolated each individual’s month-to-month fluctuations from their general baseline traits. At the baseline level, mothers and fathers who consistently reported higher insomnia symptoms across the entire year also experienced higher overall emotional distress. Looking at the changes over time revealed a cascading effect as the infants grew older.

For both mothers and fathers, higher depression and anxiety symptoms at eight months postpartum predicted worse subjective sleep quality at twelve months. This occurred even though infants typically develop more consolidated, uninterrupted sleep patterns during the second half of their first year. The researchers propose that as infant-driven sleep disruptions decline, parental distress may increasingly become the primary driver of poor sleep.

This delayed effect might reflect broader changes in family routines. During the second half of the year, many parents return to work, and partners often shift how they distribute caregiving duties. These changing demands could exacerbate stress and hinder a parent’s ability to sleep well.

The study revealed a particularly pronounced cycle for fathers. Lower sleep quality in fathers at four months postpartum predicted an increase in depression and anxiety symptoms at eight months. Those elevated mental health symptoms then predicted a decrease in subjective sleep quality at twelve months.

These findings indicate that fathers experience a continuous, cyclical relationship between sleep and mental health that stretches across the first year of parenthood. Even if fathers initially report fewer nighttime disruptions than mothers, their sleep quality still serves as an early warning sign for later emotional distress. The researchers suggest that evaluating sleep in both parents could help identify families at risk for ongoing mental health struggles.

The study does carry several caveats. The findings rely on observational data, meaning the statistical models can highlight strong predictive trends but cannot prove direct biological causality. The participant pool was also relatively homogeneous, consisting mostly of middle-to-upper-income families with healthy infants.

Most of the parents in the study scored in the subclinical range for depression and anxiety. The results might not fully translate to parents suffering from severe, clinically diagnosed psychiatric conditions. The researchers also did not analyze how one partner’s sleep loss or distress might directly impact the other partner over time.

Future studies could explore whether these predictive links are entirely unique to the postpartum period or if they reflect general adult stress responses. Regardless, the results highlight the need for healthcare providers to address both sleep and emotional well-being in new parents. Treating parental anxiety and depression may be a necessary step to improving their daily sleep quality, especially in the later months of a child’s first year.

The study, “Sleep and symptoms of depression and anxiety in mothers and fathers of infants: A longitudinal perspective,” was authored by Avel Horwitz, Yael Bar-Shachar, Dar Ran-Peled, Gal Meiri, and Liat Tikotzky.