Lead
When most people hear the words "postpartum depression," they picture the mother. Prenatal care, the boshi techo (Maternal and Child Health Handbook, issued to all expectant parents in Japan), postnatal care programs, the screening questionnaire at the obstetric checkup — the institutional entry points are designed, virtually without exception, around the mother.
But it is not only mothers who experience depression during the perinatal period. Fathers experience it in substantial numbers. The problem is that this fact remains almost entirely invisible — institutionally and culturally.
This article summarizes what peer-reviewed research from Japan and abroad shows about the prevalence of paternal perinatal depression, documents its independently observed effects on child development, and considers what fathers and their households can do given the current absence of formal support structures. This will not be a soft-focus encouragement piece. The goal is to get the facts as accurate as possible.
"1 in 10" — What That Number Feels Like in Practice
The most widely cited evidence on paternal perinatal depression is the 2010 JAMA meta-analysis by Paulson and Bazemore [1]. Pooling 43 studies covering 28,004 fathers, it estimated that the prevalence of depressive symptoms from the prenatal period through 12 months postpartum was 10.4% (95% CI: confidence interval — the range within which the true population value is estimated to lie with 95% certainty 8.5–12.7%) [1]. In the specific window of three to six months postpartum, estimated prevalence rose to 25.6% [1].
This estimate was updated in 2016 by Cameron and colleagues in a meta-analysis published in the Journal of Affective Disorders, pooling 74 studies and approximately 41,000 fathers, which produced an estimate of 8.4% (95% CI 7.2–9.6%) [2]. Across studies spanning different years, countries, and measurement tools, the line stabilizes: roughly one in ten fathers experience clinically significant depressive symptoms during the perinatal period.
Japanese data are consistent with these international figures. A longitudinal study by Suto and colleagues conducted in Nishio City, Aichi Prefecture, found that approximately 17% of fathers scored above the EPDS cutoff of 8 within the first three months postpartum [3]. A meta-analysis of Japanese men specifically by Nishimura and colleagues (2020) estimated perinatal paternal depression prevalence at 8.5% [4]. These are not extrapolations from Western samples — they are observations from within Japan, in a similar range.
Whether one reads 10% as a large or small number is a matter of perspective. But it is worth noting that maternal perinatal depression, estimated at roughly the same prevalence, has been treated as a major public health concern warranting structured screening, institutional responses, and public awareness campaigns. Applying a different standard to paternal depression — treating it as a private matter of individual resilience — is difficult to justify on the evidence.
Effects on Child Development: An Independent Pathway
A common intuition is that if the mother is managing well, paternal depression is unlikely to affect the child. The research does not support this.
Ramchandani and colleagues analyzed data from the Avon Longitudinal Study of Parents and Children (ALSPAC) — 8,431 fathers and 10,024 children in the UK — and examined the association between paternal depression at eight weeks postpartum and emotional and behavioral problems in children at age 3.5 years [5]. After adjusting for maternal postpartum depression and for subsequent paternal depression, paternal depression remained independently associated with child emotional and behavioral problems (adjusted OR 2.09), with a stronger association observed specifically in boys (adjusted OR 2.66) [5].
Subsequent work, including studies published in Lancet Psychiatry, has continued to report this pattern. Over two decades of evidence, the picture that has accumulated is: paternal depression is not a side effect of maternal depression. It has its own relationship to child outcomes, operating through a distinct pathway — most likely through direct father-infant interaction in the early months.
A statistical note that matters: these findings describe elevated population-level risk, not deterministic outcomes. An individual father experiencing depression does not doom his child to behavioral problems. The data say that on average, across large groups, the risk is elevated. That distinction is important and should not be lost.
Why It Goes Undetected
At least three structural reasons explain why paternal perinatal depression is routinely missed.
First, measurement tools may not fit. The EPDS: Edinburgh Postnatal Depression Scale — a 10-item self-report questionnaire widely used to screen for postpartum depression is the standard screen in perinatal settings and is applied to fathers as well as mothers. But depression in men more commonly presents not as classic low mood but as irritability, increased alcohol use, overinvestment in work, and physical symptoms [2]. The EPDS may not capture these presentations reliably, meaning that using the same tool with the same threshold for both parents likely underestimates the problem in fathers.
Second, institutional access points are sparse. Mothers have prenatal appointments, postnatal checkups, and infant health visits — all of which have been progressively integrated with mental health screening. In Japan, there is currently no equivalent formal structure for fathers. When fathers attend the infant health visits, there is typically no item on the questionnaire asking about the father's own mental state.
Third, cultural inhibition suppresses help-seeking. The expectation that fathers are the stable support system — and not the ones who need support — makes it harder for fathers to recognize their own symptoms, and harder still to name them to anyone else. Cameron and colleagues found that paternal and maternal depressive symptoms show a moderate correlation within the same household (r approximately 0.3) [2]. When one parent is struggling, the other is more likely to be struggling too. Yet the one who reaches professional help is overwhelmingly more often the mother.
What a Household Can Do Now
The realistic scope of individual action here is limited. Waiting for institutional screening infrastructure to develop is not a plan. But two things are available now.
The first is keeping a record of mood, sleep, alcohol use, and irritability intensity — even at the level of a brief daily note. Paternal depression tends to surface earlier in disrupted sleep quality and elevated daytime irritability than in frank low mood [2]. A log in a parenting app like Memori works, as does a paper notebook. The point is not sophisticated data collection. It is creating enough of a record that, a week later, you can look back and recognize what the past week actually looked like. That capacity to see yourself from one week's distance is often what makes it possible to notice that something has been wrong, and to decide to say so.
The second is keeping "I can go to a psychiatrist or general practitioner" in the active list of options. Japan does not yet have a designated consultation pathway for fathers in the perinatal period. But calling a municipal public health center and describing the situation is possible. Going along to the obstetric appointment of a partner and raising the question there is possible. The important move is to lower the internal threshold for what counts as "enough" to seek help. When one in ten people experiences this, being the one does not reflect individual weakness — it reflects a probability that was always in the range.
Two situations warrant bypassing the internal threshold question entirely and speaking to a general practitioner directly: sleep disruption severe enough to persist for more than two weeks, or irritability toward the child or partner that feels alarming even to yourself. Earlier is better. There is no such thing as a consultation that happened too soon.
Summary
Paternal perinatal depression exists at a prevalence of approximately one in ten, across studies conducted in multiple countries and within Japan specifically [1,2,3,4]. It is independently associated with child emotional and behavioral outcomes — not merely as a downstream effect of maternal depression, but through its own pathway [5]. Institutional support structures in Japan remain sparse. There is no equivalent to the postnatal screening visit for fathers.
Within those constraints, two actions remain available: record your state, and lower the threshold for reaching out. Being a father and having the right to attend to your own mental health are not in conflict.
References
- Paulson JF, Bazemore SD. Prenatal and postpartum depression in fathers and its association with maternal depression: a meta-analysis. JAMA. 2010;303(19):1961–1969. doi:10.1001/jama.2010.605. PMID: 20483973.
- Cameron EE, Sedov ID, Tomfohr-Madsen LM. Prevalence of paternal depression in pregnancy and the postpartum: An updated meta-analysis. J Affect Disord. 2016;206:189–203. doi:10.1016/j.jad.2016.07.044. PMID: 27475890.
- Suto M, Isogai E, Mizutani F, Kakee N, Misago C, Takehara K. Prevalence and Factors Associated With Postpartum Depression in Fathers: A Regional, Longitudinal Study in Japan. Res Nurs Health. 2016;39(4):253–262. doi:10.1002/nur.21728. PMID: 27209152.
- Nishimura A, Fujita Y, Katsuta M, Ishihara A, Ohashi K. Prevalence of perinatal depression among Japanese men: a meta-analysis. Ann Gen Psychiatry. 2020;19:65. doi:10.1186/s12991-020-00316-0.
- Ramchandani P, Stein A, Evans J, O'Connor TG; ALSPAC study team. Paternal depression in the postnatal period and child development: a prospective population study. Lancet. 2005;365(9478):2201–2205. doi:10.1016/S0140-6736(05)66778-5. PMID: 15978928.
- Sethna V, Murray L, Netsi E, Psychogiou L, Ramchandani PG. Paternal depression in the postnatal period and early father-infant interactions. Parent Sci Pract. 2015;15(1):1–8. doi:10.1080/15295192.2015.992732.
- Nishigori H, Obara T, Nishigori T, et al. The prevalence and risk factors for postpartum depression symptoms of fathers at one and 6 months postpartum: an adjunct study of the Japan Environment & Children's Study. J Matern Fetal Neonatal Med. 2020;33(16):2797–2804. doi:10.1080/14767058.2018.1560415. PMID: 30563397.