The Amazing Chain of Human Reproduction

Human reproduction truly is the irresistable force meets the unmovable object. The ‘irrestistable force’ is ‘survival of the fittest’, and the ‘unmovable object’ is ‘reliably putting together something as complex as a human being’. There are so, so, so many things which can go wrong in human reproduction, that it’s astonishing that it is so frequently successful.

Here a partial list of the links in the chain of human reproduction:

– Sexual attraction
– Sex drive
– Sexual attractiveness
– Fertility
– Potency
– Supporting the growth of a fetus …
– … without killing the mother
– Childbirth
– Romantic attraction (to keep people together long enough to care for a child for a few years)
– Romance drive
– Breastfeeding (or altenatives)
– Intent to biologically reproduce (this is more cruial when effective birth control is available)

Many people who want biological children do run into problems in at least one of these links … because complex processes have high rates of failure.

At the same time, evolution pushes reproduction pretty fiercely, so that many people who don’t want biological children sometimes end up with a pregnancy. The only birth control method that comes with a 100% guarantee of no pregnancy is castration (though interuterine devices, vasectomies, and in some circumstances, abstinence, come pretty close to 100%). Most birth control methods try to weaken or interfere with the chain – only castration breaks it.

It is suspected that men in my father’s family tend to have low sperm counts, and my own father was declared infertile as a young man. The fact that men in my father’s family tended to have few or no children even without birth control is evidence. Yet some men in my father’s family obviously managed to have biological children, including my ‘infertile’ father – low sperm count does not mean zero sperm count. Even with that loose link in the chain, the other links in the chain kept biological reproduction happening – for example, according to the comments of various people, handsome looks (i.e. sexual attractiveness) also run in my father’s family.

Based on the history of the women in my family, I most likely have at least an average level of fertility, possibly higher, and right now, my level of sexual attractiveness is high. In my case, the loose links are my lack of sexual and romantic attraction, as well as low sex and romance drives. I can, if I want to, compensate for this link with willpower (i.e. use the ‘intent to biologically reproduce’ chain) … but most people don’t have to use so much willpower to get the biological reproduction process started.

Looking at the system in abstract, it is a marvel. The chain compensates for the links which will inevitably come loose in a complex system by pushing for as many strong links as possible.

Of course, this isn’t entirely abstract for living people. It shapes our society, our relationships, our bodies, and our feelings, in short, our existence.


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5 thoughts on “The Amazing Chain of Human Reproduction

  1. “The only birth control method that comes with a 100% guarantee of no pregnancy is castration (though interuterine devices, vasectomies, and in some circumstances, abstinence, come pretty close to 100%).”

    Hey! Vasectomy is not a castration method. Castration eliminates the sex drive, vasectomy just prevents the sperm from getting out, nothing more. And it does not gives 100% guarantee. Almost 100%, but not 100%, see :

    “Early failure rates, i.e. pregnancy within a few months after vasectomy, typically result from unprotected sexual intercourse too soon after the procedure while some sperm continue to pass through the vasa deferentia. Most physicians and surgeons who perform vasectomies recommend one (sometimes two) postprocedural semen specimens to verify a successful vasectomy; however, many men fail to return for verification tests citing inconvenience, embarrassment, forgetfulness, or certainty of sterility.”

    “Late failure, i.e. pregnancy following spontaneous recanalization of the vasa deferentia, has also been documented. The Royal College of Obstetricians and Gynaecologists states there is a generally agreed-upon rate of late failure of about one in 2000 vasectomies—vastly better than tubal ligations for which the failure rate is one in every 200 to 300 cases. A 2005 review including both early failures and late failures described a total of 183 failures or recanalizations from approximately 43,642 vasectomies (0.4%), and sixty pregnancies after 92,184 vasectomies (0.07%).”

    • Ummm, I said in that very quote that castration is not vasectomy, and vasectomy is not absolutely 100%. However, I see that I omitted another method which is 100% effective in preventing pregnancy: hysterectomy.

      • Sorry, it was my fault. I didn’t pay sufficient attention when reading it for the first time back then.

  2. “Intent to biologically reproduce”

    I’m still struggling to understand what motivates people to have children. It seems the don’t know why they chose this way, and in some cases, they don’t want to talk about.

    Do you have any extra info on this matter, so you could give me some clues?

  3. Pingback: A Maravilhosa Cadeia da Reprodução Humana – Anders Bateva

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