Abstract The risks of deteriorated psychiatric symptoms/daily life functioning should be warned of in schizophrenic women during pregnancy and puerperium. The purpose of the present paper was to prospectively monitor mental status and functioning of pregnant women with schizophrenia, and investigate the effects of various supports. Subjects were 20 schizophrenic women who visited a clinic providing care and support for pregnant women with psychiatric diseases, consisting of 12 patients with psychotic deterioration (deterioration group) and eight remitted stable patients (stable group). Psychiatric assessments were performed using Positive and Negative Syndrome Scale (PANSS) and Global Assessment of Functioning (GAF) at three time-points: at the first examination, after fixed prescription during pregnancy, and after delivery. The types/doses of drugs and other non-drug-related supports (13 items) were recorded during the study period. Although a higher total PANSS score at the first examination (P = 0.004) and lower GAF scores at the first examination and even after fixed prescription (P = 0.0003) were observed in the deterioration group, those after delivery finally caught up with the levels in the stable group. Doses of antipsychotic drugs were gradually increased in the deterioration group although no significant differences in chlorpromazine equivalent doses were found between the two groups after fixed prescription. There was a positive correlation between the number of non-drug-related supports and amelioration score in PANSS (rs = 0.553, P = 0.012). These findings suggest that comprehensive intervention is a requisite in pregnant schizophrenic women, especially with psychotic deterioration, and that non-drug-related supports may also contribute to maintenance of good and stable mental status in these patients.