I'm going to go back a little further than the time of John Colicos because the subject is too deep to start from modern times. Before we can discuss modern attitudes adequately we need an understanding of historic perspectives because everything derives from there.
In the historic context there was a sharper divide between the classes than Colicos' time and this often dictated the age at which it was considered acceptable to begin childbearing.
Notwithstanding the absence of genuinely scientific contraception at that time, although some evidence exists that contraception was practiced according to belief, local custom and sometimes even witchcraft..!!
Plants such as hawthorn, willow and ivy were alleged to show sterilising properties when drunk. Natural substances could be applied to the genitals before or after sex, creating a chemical barrier that effectively kills sperm. Substances could also form into solid plugs, pessaries or suppositories, which a woman could insert to create both a physical and chemical barrier. Ancient Egyptians used honey, acacia and crocodile dung..!!
Besides these methods though, the social considerations between the classes were significant.
Women of the poorer class tended to have a large number of pregnancies because... well... women have needs and nature takes its course. In most societies, bearing children was what women were "meant to do". The high infant mortality rate meant that producing as many babies as possible was the only real way to ensure that a family of any size could reasonably be assured.
Large families were considered acceptable among the poor because the children became a part of the workforce from an early age. Also, they would be the ones who would also care for their parents when they became too old to work and needed the younger generation to house, clothe and feed them in their old age.
It was not unusual for girls to begin child bearing almost from menarche. In England, the most prominent case of this was King Henry VII. His mother, Margaret Beaufort was married at the age of 12 and her new husband wasted no time in consummating the marriage. Margaret became pregnant very soon after her wedding and was only 13 when in 1457 she gave birth to her son, Henry Tudor who in 1485 defeated Richard III at Bosworth Field, ended the Plantagenet Dynasty and founded the Tudor Dynasty. He was the father of Henry VIII and Grandfather of Elizabeth I. Not bad for the product of a pre-teen bride.
For the rich, children were necessary not so much for economic reasons but to provide an heir.
Women of wealthy families tended to have fewer pregnancies and a lower infant mortality rate than the peasant class. As long as there was an heir - and a male one at that - to carry on the family name and keep the family rich and powerful.
Keeping the gene pool as "pure" as possible was ensured by arranged marriages between families. Very often, a wife was nothing more to her husband than a brood mare.
The upshot of all this is that the production of children was driven by circumstances. This notion of "Fruit on the vine" is poetic and all very nice in its place. But if you're a peasant farmer, with a wife and you've got to pay your dues to the Lord of the manor, you need hands in the fields and a somebody to care for you in your old age.
If you're the highest in the land, you need an heir and if one wife won't give you the heir you need, you get rid of her and get a new one. Henry VIII had six, executed two, divorced two others and split with the church of Rome throwing the country into decades of religious war.
That was the real, harsh, nitty gritty of childbearing in historic times.
Poetry is all nice and good in its place and it's a luxury we can afford these days, but let's not forget where we're coming from.
Taking this into account, is there such a concept as too early or too late? Limitations on human endurance can be mental, if the person is young and physical, if the person is older. Certainly, the older parents are more established and are likely to provide a better standard of life, but by the time the children are reaching the apex of their development, they would be mid to late fifties, whereas a young couple, like the one I used to know when I was living in my last flat, was less experienced when they started their family, but now, ten years later in their thirties, both have a head starter on their elder counterparts, having gone through the process before they had reached their full physical maturity. Does that have any kind of impact?
They say age is a state of mind. Is it possible that the mind can be adjusted to compensate for any difficulties, according to how old the parents are, or does the later stage of human development make a more balanced parenthood likely?