An intimate relationship is an interpersonal relationship that involves physical or emotional intimacy. Although an intimate relationship is commonly a sexual relationship, it may also be a non-sexual relationship involving family or friends. Emotional intimacy is an essential aspect of a healthy . Feelings of liking or loving may prompt physical intimacy. However, emotional intimacy may or may not be present alongside physical intimacy depending on the relationship. Physical intimacy is characterized by romantic love, sexual activity, or other passionate attachment. Relationships of this nature play a central role in the overall human experience. People desire to belong and to love, desires that can be satisfied within an intimate relationship. Such relationships allow a social network for people to form strong emotional attachments. Intimacy involves the feeling of being in a close, personal association and of belonging together. It is a familiar and very close affective connection with another as a result of a bond that is formed through knowledge and experience of the other. Genuine intimacy in human relationships requires dialogue, transparency, vulnerability, and reciprocity. In human relationships, the meaning of and level of intimacy varies within and between relationships. In anthropological research, intimacy is considered the product of a successful seduction, a process of rapport-building that enables parties to confidently disclose previously hidden thoughts and feelings. Intimate conversations become the basis for "confidences" (secret knowledge) that bind people together. Sexual relations and moments of intimacy often decline significantly after the delivery of a newborn. Studies show that extreme sleep deprivation is the most common response from women on why they are less sexually active with their spouse. Due to lack of sleep and the obligations of taking care of the baby, sexual intimacy becomes a lower priority. Women viewed themselves as being unattractive, not because their spouse expressed this.