Demographic and medical consequences of the postponement of parenthood

Abstract

BACKGROUND Across the developed world couples are postponing parenthood. This review assesses the consequences of delayed family formation from a demographic and medical perspective. One main focus is on the quantitative importance of pregnancy postponement. METHODS Medical and social science databases were searched for publications on relevant subjects such as delayed parenthood, female and male age, fertility, infertility, time to pregnancy (TTP), fetal death, outcome of medically assisted reproduction (MAR) and mental well-being. RESULTS Postponement of parenthood is linked to a higher rate of involuntary childlessness and smaller families than desired due to increased infertility and fetal death with higher female and male age. For women, the increased risk of prolonged TTP, infertility, spontaneous abortions, ectopic pregnancies and trisomy 21 starts at around 30 years of age with a more pronounced effects >35 years, whereas the increasing risk of preterm births and stillbirths starts at around 35 years with a more pronounced effect >40 years. Advanced male age has an important but less pronounced effect on infertility and adverse outcomes. MAR treatment cannot overcome the age-related decline in fecundity. CONCLUSIONS In general, women have partners who are several years older than themselves and it is important to focus more on the combined effect of higher female and male age on infertility and reproductive outcome. Increasing public awareness of the impact of advanced female and male age on the reproductive outcome is essential for people to make well-informed decisions on when to start family formation.

Educational differences in timing and quantum of childbearing in Britain

“…However, postponement may result in a reduction in the total number of children achieved by highly educated women as a result of the decline in fecundity at older ages (Leridon and Slama 2008;Schmidt et al 2012), the influence of cultural age timetables (Settersten and Hagestad 1996;Billari et al 2010), and the downward adjustment with rising age of fertility intentions (Berrington 2004;Liefbroer 2009;Iacovou and Tavares 2011).…”

“…If recent cohorts of women are postponing their fertility with the intention of having children later in their life courses, then rates of entry into motherhood and progression to subsequent birth orders at older ages should be higher among more recent cohorts; i.e., postponement will be followed by fertility recuperation (Frejka and Calot 2001;Frejka 2012). However, there are a number of biological and social reasons why those who start their childbearing at late ages may end up with fewer children, not least constraints arising from the end of the reproductive age range (Billari and Borgoni 2005;Billari et al 2007;Schmidt et al 2012). Since it tends to be the most educated women who are more likely to postpone entry into motherhood, educational differences in completed family size will result at least partly from this timing−quantum interaction (Kohler, Billari, and Ortega 2002;Billari and Borgoni 2005).…”

Future Fertility in Low Fertility Countries

“…In Western, Northern and Southern Europe as well as Japan, the mean age of mothers at first birth has reached 28-30 years, 4-6 years later than in the early 1970s (Schmidt et al 2012). The frequency of childbearing has increased most rapidly at advanced reproductive ages, including women aged over 40 (Sobotka et al 2007;Prioux 2005).…”

“…The higher a woman's age when she attempts to become pregnant, especially above 35 years, the longer the waiting time for a pregnancy to occur, resulting in a lower chance of achieving a pregnancy and a higher risk of miscarriage if there is a pregnancy (Schmidt et al 2012;Menken 1985; see also Section 2.7.1). Furthermore, man's age has been identified as an independent risk factor for infertility (Dunson et al 2004; Section 2.7.2).…”

Concerns about One’s Own Future or Securing Child’s Future: Paradox of Childbearing Decision Making

“…Women interviewed in this study expressed concerns about the continuity of married life. It seems that the relationship between two partners affect the formation of reproductive decisions [43] and reports related to reproductive behavior emphasize the importance of the interaction between spouses at the time of childbearing decision making [44] [45]. Also, Pezeshki et al (2005) suggested on the basis of their study that couple may have children in order to strenghten the marital relationship [13].…”