(Paris) The fertility of women after 40 years has never been so high since 1979, in particular because of the lowering of the age at the first child, but also of the births resulting from a late “repartnering”, according to a study published Monday by INSEE.
From the end of World War II until the end of the 1970s, late births had steadily declined at first, because the mothers of the “baby boom” children were young, and then because the large families (four children and more) have become scarce.
But from 1979, the trend was reversed, notes INSEE. To the point that in 2019, “late fertility” more than tripled compared to the lowest reached at the end of the 1970s, specifies the National Institute of Statistical Studies. Thus the fertility rate of women aged 40 to 50 reached 0.102 children per woman in 2019, against 0.029 in 1979.
This development is “to be placed in the general movement of increase in the average age at childbirth since the mid-1970s”, which is explained by “the lengthening of studies, later pairing, the desire to be stabilized in his professional life before having children, ”analyzes the study.
Since couples start having children later, the probability increases that the last of the siblings will be born when their mother is already in her forties: thus, one in two late births concerns families where the baby has been preceded by one or more elders ( s), from the same couple.
But the phenomenon is also due to “more frequent repartnering”, which in many cases translates into “the desire to have a child from the new couple”: in 10% of late births, the mother had already had children. from a previous union, and in 20% of cases, the parents had no children in common.
So much so that, of all the children born in 2019 to a mother over 40, more than a quarter were their mother’s firstborn. A proportion that even rises to 35% among executive mothers.