Differential Fertility: A Comparative Study of Islam and other Religions and Analysis of Concepts of Religions About Fertility in Southern Punjab, Pakistan 73 Differential Fertility: A Comparative Study of Islam and other Religions and Analysis of Concepts of Religions about Fertility in Southern Punjab, Pakistan *Nadeem-Ud-Din **Fateh Muhammad Burfat ***Ameer Ali Abro Abstract The most important reason for studying population is to gain better understanding how societies function and change. In the study of demography, fertility is the most important and perhaps the most complicated aspect of the population.it plays a significant role in the size, composition and distribution. The general objective of the study is to provide information about differential fertility and comparison of religious school of thoughts regarding fertility and situation analysis of Southern Punjab, to evaluate the religious concepts and their impacts on fertility. The focus of this research is to unearth the religious concepts related to fertility and situation analysis of southern Punjab through comparative and sociological observations, therefore the present study is exploratory in nature, the research has been conducted through review of religious literature related to fertility and its comparative analysis and the research has been conducted with personal and professional dialogue with married persons to collect the information hence the methodological approach is both Qualitative and Quantitative. It was revealed that by the changing of time most of the religions are fluctuating their views through churches, scholars, and sects. In Hinduism there is no any proper learning’s about fertility, birth control or family planning but they accept most of the methods for birth spacing, in Christianity Ideally Family planning is prohibited but due to situations and requirements of circumstances it is going to acceptable at some stages. According to Jewish views ideally it is not allowed but in some situation it is acceptable and life of women is important to save if birth control is required. Islam have its clear concept about family planning and Islam accept most of the situations according to need and time requirements in the light of various Hadith it is also observed that the Holy Prophet (PBUH) was also recommended the “Azl” a type of fertility control. Keywords: Differential fertility, fertility, demography, comparative religions, birth control, southern Punjab, Pakistan *Research scholar, Department of Sociology University of Karachi. **Professor and ex. Chairman Department of Sociology, University of Karachi, Karachi. ***Deputy District Officer Social Welfare, Government of Sindh.