The first visible outcome of the fertility process is the birth of the first child. The first birth marks a woman's transition into motherhood. It plays a significant role in the future life of each individual woman and has a direct relationship with fertility. The age at which child bearing begins influences the number of children a woman bears throughout her reproductive period in the absence of any active fertility control. For countries in sub-Saharan Africa, where contraceptive use is relatively low, younger ages at first birth tend to boost the number of children a woman will have. However, even when family planning is widespread, the timing of first births can affect completed family size if contraception is used for spacing but not for limiting fertility. The birth of a child is an event of great social and individual significance and its importance is recognised in all human societies. It signifies the transition of a couple into a new social status, i.e. parenthood with its related expectations and responsibilities. It marks the sexual and social maturity of the mother and the visible consummation of sexual intercourse . The relationship between age at first birth and overall fertility in developing countries is generally an underdeveloped area as far as demographic research is concerned. Fertility analysts generally assume that child bearing only occurs within marriage. Then they treat age at first marriage to be a major proximate determinant of fertility. This assumption might have been true in most traditional societies, where births out of wedlock were not accepted and virginity was a prerequisite for marriage. This assumption, however, does not hold true in modern times, where a large number of children is born outside marriage. These facts have been the major motive of conducting the current research. This study examines the reproductive behaviour of Tanzanian women. The study found the average age at first sexual intercourse to be 16 years; age at first marriage to be 17 years, while average age at first child bearing was estimated to be 18 years. By age 15, almost 10 percent of juvenile women have given birth. This study furthermore found that 41 percent of all first live births resulted from premarital conceptions. Out-of-wedlock births account for 24 percent of all first births in Tanzania according to the 1996 TDHS. The education of a woman, place of residence, and religion play the greatest roles in influencing age at first birth in Tanzania. The striking results were place of residence as it was found that rural residents have a higher mean age at first birth than women living in Dar es Salaam. Dar es Salaam women has the lowest mean age at first birth. Moslems have lower age at first birth than Catholics. There is also a strong relationship between age at first birth and age at first intercourse also with infant and child mortality. The results indicate that the younger the age of the mother at the birth of the first child, the higher the chances that the child dies. The study of current levels and trends of fertility showed that, on the average, a Tanzanian woman bears 6 children. Between the 1960s and early 1980s, an average of 7 births per woman prevailed in Tanzania. The declining fertility in Tanzania was confirmed by the analysis of the decomposition of the change of the total fertility rate (TFR) between two TDHSs. It found that natural fertility control is being gradually replaced by contraceptive use although the percentage of women using contraception is still very low. The reduction in infant and child mortality, rising numbers of women attending schools, and a rise in age at first birth are among the factors responsible for the decline in fertility in Tanzania. Education on the other hand has played a major role in raising age at first birth. Education either delays first intercourse and subsequently birth as pregnant schoolgirls are prohibited to attend formal schools or it effects the acceptance of contraception to delay first conception. Specifically, this study establish that there is an inverse relationship between age at first birth and fertility. Marriage is a weak factor in explaining fertility in Tanzania. Women in polygamous unions had fewer number of children ever born than those in monogamous unions in Tanzania. Moslems have a lower fertility than Catholics. Women residing in urban areas have fewer children than those in the rural areas. Women's education is the strongest predictor of the use of contraceptives in Tanzania. Catholic women are less likely to use contraceptives than Moslems. Tanzanian women residing in rural areas are less likely to use contraception than their counterparts residing in urban areas. Although age at first birth did not show any significance, age at first intercourse, age at first marriage and current age are highly related to contraceptive use. Variation in age at first sexual intercourse; marriage; and birth, and the extent of practising contraception are found to depend mainly on religion, place of residence, and the age of a woman. It is important therefore to design separate programmes to raise age at first birth and to lower fertility according to the findings related to religion, place of residence, and target juvenile women separately.

Die Dissertation fragt nach den Ursachen der spezifisch niedrigen Geburtenrate in Ost- und Westdeutschland, die seit Mitte der siebziger Jahre deutlich unter dem Reproduktionsniveau liegt. Theoretisch wird die Frage behandelt, inwiefern die gewandelte gesellschaftliche Stellung der Frau – insbesondere ihre höhere Bildungs- und Erwerbspartizipation – mit der Verbreitung geringer Kinderzahlen in Verbindung steht. Für die Analysen werden Scientific Use Files der Mikrozensen 1973 bis 2008 verwendet; diese repräsentieren jährlich 0,7 Prozent der deutschen Bevölkerung. So kann gezeigt werden, dass innerhalb vergleichbarer soziostruktureller Gruppen kaum ein Rückgang der Kinderzahlen auftrat. Differenziert nach Berufsbildungsabschluss, Erwerbstätigkeit und Finanzierung des Lebensunterhaltes zeigt sich, dass einzig Frauen ohne Berufsbildung sowie Frauen, die das Hausfraumodell leben, durchschnittlich 2,0 Kinder haben – dies ist sowohl im Jahr 1982 wie auch 2008 in Westdeutschland der Fall. Innerhalb der Gruppe der erwerbstätigen Frauen liegen die Kinderzahlen je Frau deutlich niedriger. Die Gruppe der Hausfrauen, die ihren überwiegenden Lebensunterhalt durch ihren Ehemann finanziert, hat sich in Westdeutschland im Zeitvergleich seit dem Jahr 1982 von 50 auf 25 Prozent der Frauen halbiert. Dieser strukturelle Wandel hin zu einer unabhängigen weiblichen Lebensführung führte in Westdeutschland zu Kinderzahlen weit unter dem Reproduktionsniveau. Die empirische Analyse zeigt, dass strukturtheoretische Modelle mit klassischen Variablen wie Familienstand, Erwerbsumfang und Einkommen die Varianz der Kinderzahl heute besser erklären können als noch in den achtziger Jahren. Im Fazit scheint ein gesellschaftliches „cultural lag“ auf – die gesellschaftliche Unterstützung zur Vereinbarkeit von Beruf und Familie ist offensichtlich zu gering, so dass die Emanzipation der Frau in Deutschland den negativen Effekt niedriger Geburtenraten hervorbringt. / The study focuses on the causes of low birth rates in eastern and western Germany, which has been below the level of reproduction since 1975. Theoretically the changing position of women in society is considered and the possible connections between higher female education, the spread of female employment and low fertility rates are discussed. The analysis is based upon scientific use files of the German micro census from 1973 up to 2008; the data represent annually 0.7 percent of the German population. It is shown, that there is no decline in fertility within similar socio structural subgroups. Controlled by educational/vocational training, employment and female income (financial independence) it is shown that only women with no vocational training and women with no own income have 2.0 children per women – this result is significant for Western Germany in 1982 as well as in 2008. Within the group of employed women the mean number of children is much lower. But the group of housewives declined in half from 50 to 25 percent between 1982 and 2008. This structural change toward female independent lifestyle leads to a very low birth rate in Germany. The empirical analysis shows that classical models using structural variables like family status, employment and income are able to explain a considerable higher variance of birth rates today. Summing up there appears to be a “cultural lag”: women get emancipated, but the public support and the compatibility of work and family stays low, as well as the birth rates of employed women led to low overall birth rates.