This study examined the perceived causes of loneliness of pregnant women and mothers during the first year after childbirth experience. These were compared with the causes of loneliness of women in the general population. 91 pregnant women, 97 women during the first year following childbirth, and 208 women from the general population (M age = 30.4, SD = 10.4) answered a 29-item Loneliness Antecedents Questionnaire. In the questionnaire were 5 dimensions of sources of loneliness, namely, Personal Inadequacies, Developmental Deficits, Unfulfilling Intimate Relationships, Relocation/Significant Separation, and Social Marginality. Sources of loneliness were significantly different amongst the three groups. The differences were confined to the Personal Inadequacies, and the Relocation/Significant Separation subscales. In both, women from the general population had the highest mean subscale scores.