Differences in infant feeding methods at one month postpartum among women with psychiatric disorders and factors influencing exclusive breastfeeding.

BACKGROUND: Women with psychiatric disorders tend to have lower rates of exclusive breastfeeding despite of the benefits. Maternal use of psychotropic drugs has been suggested to influence their infant feeding methods. In this study, we retrospectively investigated differences in infant feeding methods (exclusive breastfeeding, formula feeding, and mixed feeding) among mothers with psychiatric disorders one month postpartum (n = 149), as well as the factors influencing infant feeding methods. METHODS: Data on the infant feeding methods of individuals with schizophrenia spectrum disorders (SSDs, n = 32), bipolar disorders (BDs, n = 23), depressive disorders (DDs, n = 33), and anxiety disorders, and stress-related disorders (ASRDs, n = 61) were extracted from medical records at a single institute between 2008 and 2024. Differences in infant feeding methods among the disorder groups, and the influences of individual factors, including the regular use of psychotropic drugs at the time of childbirth, as well as newborn information, on the infant feeding methods were assessed. RESULTS: Among the diagnostic groups, significant differences in infant feeding methods were observed (F = 6.52, p = 3.64 × 10⁻⁴), with a higher rate of formula feeding in the SSD group (72%) than in the other groups (BDs, 35%; DDs, 24%; ASRDs, 35%). In the SSD group, formula feeding was significantly correlated with the presence of antipsychotic (beta = 0.52, p = 2.93 × 10- 3). In the non-SSD group, formula feeding was significantly correlated with the regular use of benzodiazepines (beta = 0.43, p = 3.46 × 10- 6), the number of benzodiazepines used(beta = 0.38, p = 3.71 × 10- 5), the diazepam equivalent (beta = 0.31, p = 6.78 × 10- 4), and the number of psychotropic drugs used (beta = 0.41, p = 8.42 × 10- 6). CONCLUSION: Individuals with SSDs were more likely to choose formula feeding because of the use of antipsychotics at the time of childbirth, whereas individuals with non-SSDs tended to choose formula feeding because of psychotropic polypharmacy, including the use of benzodiazepines. These findings suggest that providing education on the safety of antipsychotics for patients with SSDs and avoiding polypharmacy in non-SSD patients might help promote exclusive breastfeeding.