Many religions teach that sexual relations should only occur for the purpose of propagation. Therefore, contraception and the pleasure principle should not be considered. It is interesting to note that in a way biological insticts dicatate same but only after the female gives birth. Many women complain of loss of libido after giving birth. That of course lasts for up to one year for some, a lifetime for others. Some women not only have a loss of libido but become quite depressed and, therefore, interest in sex is far down on their list. Psychologists try to treat that phenomenon and some women are put on antidepressants, because that attitude puts a tremendous stress on their marriage. That is perhaps nature’s way of telling the female that now you had a child and you did your part in propagation of the species. Now it is time to rest and nurture this child to ensure its survival before you go on to have more children. Nature, protects the offspring to make sure the species continues. When the child is healthy and growing, often libido returns and more children are born, or not depending on the fertility of the female. Loss of libido after childbirth therefore, is not pathological and should not be of concern. Biology, restores it when the time is right. The worse thing is if one does not understands this phenomenon, and then anxiety sets in which then leads to further deterioration of the natural development of the natural biological instincts which is attraction to the male- libido, and the pleasure principle which is necessary for the propagation of the species and was set by the natural forces of nature.