Some studies have demonstrated that breastfeeding can Background: protect mothers from postpartum depression; therefore, we examined the association between postpartum depression and lactation status at one month after delivery at a Japanese perinatal center.We reviewed the obstetric records of all (total 809) nulliparous Methods: healthy women with vaginal singleton delivery at 37-41 weeks' gestation at our institute between July 2018 and June 2019. A face-to-face interview with the women was conducted on admission for delivery to ask whether or not they hoped to perform exclusive breastfeeding for their babies, and an additional interview was conducted one month after delivery to ask about their feeding methods currently. Maternal mental status was examined based on the scores using the Edinburgh Postnatal Depression Scale (EPDS), and women with EPDS scores of ≥9 points were regarded as 'positive screening'. 592 women (73.1%) hoped to perform exclusive breastfeeding for Results: their babies on admission. Of these, at one month, 442 (74.7%) performed exclusive breastfeeding, while 150 (25.3%) performed mixed or artificial feeding. The average EPDS scores and the incidence of EPDS scores ≥9 points in the women performing exclusive breastfeeding were 4.3 ± 3.6 and 14.3% (63/442), respectively. They did not differ from those in the women performing mixed or artificial breast feeding [4.2 ± 3.7, p = 0.60 and 13.3% (20/150), p = 0.78].Development of postpartum depression does not seem to be Conclusion: associated with incomplete breastfeeding at our hospital, and therefore there are other risk factors indicated in the development of postpartum depression.PubMed Abstract | Publisher Full Text 3. Pearlstein T, Howard M, Salisbury A, et al.: Postpartum depression. Am J Obstet Gynecol. 2009; 200(4): 357-364. PubMed Abstract | Publisher Full Text | Free Full Text 4. Takeda S, Takeda J, Murakami K, et al.: Annual Report of the Perinatology Committee, Japan Society of Obstetrics and Gynecology, 2015: Proposal of urgent measures to reduce maternal deaths. J Obstet Gynaecol Res. 2017; 43(1): 5-7. PubMed Abstract | Publisher Full Text 5. Honjo K, Kimura T, Baba S, et al.: Association between family members and risk of postpartum depression in Japan: Does "who they live with" matter? -The Japan environment and Children's study. Soc Sci Med. 2018; 217: 65-72. PubMed Abstract | Publisher Full Text 6. Muchanga SMJ, Yasumitsu-Lovell K, Eitoku M, et al.: Preconception gynecological risk factors of postpartum depression among Japanese women: The Japan Environment and Children's Study (JECS). J Affect Disord. 2017; 217: 34-41. PubMed Abstract | Publisher Full Text 7. Iwata H, Mori E, Tsuchiya M, et al.: Predictors of depressive symptoms in older Japanese primiparas at 1 month post-partum: A risk-stratified analysis. Jpn J Nurs Sci. 2016; 13(1): 147-155. PubMed Abstract | Publisher Full Text 8. Suzuki S: Mother's biggest worry at 2 weeks after delivery (in Japanese). Clin Gynecol Obstet (Tokyo). 2017; 71(11): 1107-1111. 9. Figueiredo ...