The  time when women choose to have babies has changed through history.  At  the beginning of the 20th century, Doctors told women to wait until they  were at least 24 to become pregnant, because it was known that giving  births earlier resulted in "damaged" babies due to the lack of medical  knowledge at the time.  Waiting  too long, however, also resulted in fertility problems.  Of course,  much of this advice went by the wayside as lack of reliable  contraception led to birthing at a younger age anyway.
The  Great Depression put a real "stymie" on women choosing to have children  in their twenties.  Lack of income reduced interest in sex and men told  their wives to not fall pregnant.  At least this is what we are told.   
War  in the late 1930s saw all of this self-control fall away as couples  fell pregnant with the view that one could be dead tomorrow.  Even in  1942 a doctor said people were selfish and wanted creature comforts more  than children.  How he came to this conclusion is a mystery.  With a  war on there wasn't much to buy.  All labor was directed to the war  effort.
After  the War, the predilection for early childbirth continued.  Male  dominated society saw women tied to the home.  When war ended people  wanted to get back a stable family life as soon as possible.  Too much conflict and death can do this. 
The  birth control pill was established in the 1960s.  This was a whole new  ball game.  Women could now choose when to have children.  By the 1970s  the number of women giving birth in their thirties doubled.  This rate  has continues to rise to the present day.
Culture  changed along with this.  More women entered the workforce as having  two incomes was necessary for the high demand way of life that was  developing.  Two incomes were not necessary for a couple to live in past eras.   People today want everything that our forebears did not have like cars,  homes, air conditioning, private schools, quality health care and more  importantly, safe workplaces.
Will  the future continue along the same path.  We do not know.  Technology  keeps moving forward.  It is possible that eventually the human body  will not be necessary to carry babies.  They are conceived in a dish so  perhaps they will be "carried" in some sort of chemical container.
✴ Culture by Ty Buchanan ✴




