Posted in Science & Nature

Caesarean Section

(To read about how babies are made and born, read the From Cell to Birth miniseries! https://jineralknowledge.com/tag/arkrepro/?order=asc)

Most animals give birth through a female’s vagina. Of course humans are the same when it comes to natural birth, but nowadays, it is not uncommon to find women wanting a caesarean instead of the traditional method. A caesarean (also called C-section) is a surgical procedure where the fetus is taken out by cutting through the lower abdomen into the uterus. The history of caesareans is quite dark. Back in the old days when medicine was not advanced, caesareans were mostly used to rescue fetuses from mothers who had died during childbirth. The first record of a successful caesarean where the mother survived dates back to the 1500s. Many people believe the word “caesarean” came from the Roman emperor Julius Caesar, who was allegedly born via a caesarean. However, it was rare for caesareans to be performed in Roman times and even if they were, the mothers almost certainly died in the process. Given that his mother was alive and healthy well into his adulthood, it is highly unlikely that Caesar was born by caesarean (there are no concrete records of it either).

There is much debate to whether a caesarean is better or worse than natural birth (except in emergency situations where a caesarean is required). According to research (in cases without known risks to the fetus), the mortality rate is definitely higher in babies born by caesarean compared to those born naturally. This is most likely due to a caesarean bypassing some of the physiological changes that occur during vaginal birth.

Another debate is about the use of general versus regional anaesthesia (spinal block) when doing a caesarean. A fascinating fact about childbirth is that when a baby is born, it cries to expand its lungs but then quietens down for about an hour (unless it is in pain or there is some stimuli). This is possibly a mechanism to allow bonding between the mother and baby. New mothers often remember the moments following the birth of the child as extremely emotional and blissful. Contrastingly, mothers who are under general anaesthesia and not awake when their child is born bond less with the baby initially (some mothers do not even recognise the baby as their own). Thus, unless it is an emergency caesarean, a spinal block (which allows the mother to be awake and painless) is preferable over general anaesthesia.

Lastly, it is common tradition to cut the umbilical cord straight after the child is born. But is this okay? When the fetus is in the uterus, it shares its cardiovascular system with the placenta. The umbilical cord connects the two and carries blood to and fro. At any given point, the placenta contains 30~50% of the fetal blood. If the umbilical cord is suddenly cut, the fetus essentially loses this blood, being born in a state of low blood volume. If you look at the umbilical cord, you can see that it is about 1m in length, which is enough for the baby to be put next to the mother’s breasts for breastfeeding and bonding. Perhaps we are cutting the cord too soon, not letting the blood flow back from the placenta to the fetus.

If you think about it, humanity has been giving birth without too many problems to survive generation after generation for 200,000 years (otherwise we would not exist). Although the mortality rate was high, Mother Nature has optimised childbirth over time through evolution. Ergo, it is possible that modern medicine is intervening too much in a natural process. We must always consider whether medical advances are helpful or harmful to us.

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Posted in History & Literature

To End All Wars

In his play Lysistrata, Greek playwright Aristophanes gives a comic account of one woman’s extraordinary mission to end the Peloponnesian War – a 30 year old war between Athens and Sparta. How did one woman bring an end to such a deadly war?

In the play, Lysistrata (the female protagonist) becomes sick and tired of men treating women like simplistic hedonists incapable of functioning on their own. She believes that the war is a result of irrational men making stupid decisions and the long war is a waste as young, nubile women are aging away. She holds a convening of the women of various city states and proposes that the women must rise up to stop the war. Lysistrata’s plan is simple: withhold sex from the men until they cave (i.e. a sex strike). The women are reluctant at first, but agree to join her. They then take over the acropolis of the city, setting up a safe haven for women, barring any man from entering.

The men initially scoff at this revolution and try repeatedly to lay siege on the acropolis. However, they fail and the women continue to not provide any sexual pleasures to any male. The men constantly make snide comments about how women are hysterical and only seek pleasure, but sooner or later, they become desperate for sex. One by one, desperate men (sporting “burdens”, i.e. erections) come to the acropolis, pleading for relief (funnily, some women desert the acropolis in desperation for sex as well). The women take the men in, but only to tease them and leave them disappointed.

Eventually, the men (of both Athens and Sparta) cave and surrender, agreeing to end the war. There is a hilarious scene during the peace talks where Lysistrata brings out a stunning young girl named Reconciliation in front of the men, quashing any complaints or objections. Even the men who protest against the women’s demands are overcome by their lust and want(/need) for sex. Once peace is declared, the men and women all come together in the acropolis for singing and dancing, celebrating the women’s success in ending the war.

Although the play is only a comic exploration of the battle of the sexes, it clearly shows the power women have over men, and how they can use that power to easily control men.

Posted in Science & Nature

From Cell To Birth: Childbirth

The onset of labour signals that the birth of the child is imminent. Strong contractions of the uterus under the influence of oxytocin cause intense pain for the mother. This escalates as oxytocin creates a vicious cycle for more and more powerful contractions. Other signs include a bloody show, where blood and mucus leaks out, and the water breaking, where amniotic fluid bursts out as the membranes rupture.
When the cervix has fully dilated to 10cm wide, the baby is ready to come out, and this is the end of the first stage. It may take over 24 hours for this stage to be over – all the while the mother is in extreme pain as her body transforms for the process.

The second stage concerns the delivery of the baby, and follows a precise series of steps.

  1. The baby, oriented head-down, facing either right or left, leans against the pelvis.
  2. The baby begins to descend, passing through the pelvis.
  3. It flexes its head as it comes through the cervix, turning towards the mother’s back as it does so.
  4. As the head crowns, the baby turns back to its side-facing position so the shoulders can come out.
  5. The rest of the body comes out with the shoulder. Forceps may be used to help.

The passage of such a large head and body is only possible through the massive dilation of the cervix, the stretch of the vagina, and the soft, malleable skull of the baby (a newborn’s head often looks conical and alien-shaped). Quite often, the opening of the vagina is not wide enough, and the opening may be cut open more to ensure it does not rip.

After the baby is safely delivered, the umbilical cord and the placenta are also delivered, thus ending the third stage (afterbirth). The cord is clamped and cut, and the baby is then thoroughly checked to ensure it is healthy and has no developmental issues.

Although in the past childbirth was extremely risky and often led to the death of the mother and/or baby in the process, nowadays protocols and health professionals ensure that both survive the procedure, thus ending the incredible 40-week journey until the birth of a new life. Only after understanding the arduous steps and the risks a mother takes to give birth to her child can one truly appreciate the value of life.

(Full series here: https://jineralknowledge.com/tag/arkrepro/?order=asc)

Posted in Science & Nature

From Cell To Birth: Fertilisation

Once the sperm enters the vagina, the real battle begins. The vagina is highly acidic, an environment in which sperm can only survive 2~3 hours. It is crucial for the sperm to enter the uterus through the cervix, but only 1% of the 200~300 million sperm make it through.

Even within the uterus, they must brace harsh conditions as they travel against gravity. After about 5 hours of intense swimming, the sperm reach the top of the uterus. Here they face a choice: go left or go right. Half the sperm make the wrong choice and head down the eggless fallopian tube and ultimately die. The rest navigate their way through the maze of folds in the fallopian tube, often getting lost or sticking to the wall thinking that it is an egg.

About 200 sperm finally make it to the egg, which sits in the ampulla of the fallopian tube. But as always, there is competition even at this final moment. Only one sperm can win the race, and the fastest one will ultimately produce a new life.

When the first sperm touches the egg, a series of chemical reactions occur, essentially “priming” the sperm. This causes it to start the acrosome reaction, where it releases a hoard of enzymes from its head, digesting away the covering shell (zona pellucida) of the egg. It then becomes supercharged, using all of its energy to drive itself inwards until it reaches the oocyte within. As soon as this happens, the tail breaks off, and one final chemical reaction as the calcium level spikes occurs to release more enzymes that prevent the acrosome reaction in other sperm. It also solidifies the zona, forming an impenetrable shield to prevent other sperm coming in (polyspermy can lead to a failed pregnancy).

The calcium spike that causes the above cortical reaction also triggers the egg to divide, so that it reaches the most mature stage. The winning sperm can then combine its nucleus with the oocyte, forming the 46 chromosomes that will set the genetic basis of the new zygote (first stage of a baby).

To reach the egg, the sperm must travel over 20cm – beating its tail over 20,000 times. The probability that a certain sperm will fertilise the egg is 1 in 500,000,000.
Life starts under a near-zero probability condition.


(Full series here: https://jineralknowledge.com/tag/arkrepro/?order=asc)

Posted in Science & Nature

From Cell To Birth: Sex

The two copulatory organs are the penis and the vagina. Both are designed to maximise the chance of a new life being conceived.

The penis is normally flaccid, but when stimulated through touch or erotic images and thoughts, it can become stiffened to eight times its original size. Contrary to certain slang words, the penis contains no bones – it is merely a sponge.
When the brain signals the penis to become erect, the sponge is relaxed, letting blood flood in, filling it like a balloon. This combined with two muscles and the sheath enclosing the penis achieves the erection which is critical in sex.

The vagina is shaped to perfectly accommodate an erect penis, and receives the sperm that will eventually fertilise the egg. As sex involves the piston movement of the erect penis within the vagina, it is bound to suffer chafing. So nature developed Bartholin’s glands that produce a lubricant, smoothing the process.
The clitoris actually shares its origin with the penis, and thus swells when sexually excited. It is also extremely sensitive.

The goal of sex is simple – excite the penis enough for the man to achieve an orgasm (note that female orgasm is optional, but ideal, for conception). When a threshold is reached, the brain sends out strong signals to squeeze sperm out from the epididymis, and seminal fluid from the prostate and seminal vesicles. The combined fluid (semen) shoots through over half a metre of tube until it is ejaculated out.
The semen collects in the vagina, where the cervix laps up the semen and transports it into the uterus. From here, the sperm’s adventure begins, facing many troubles to conceive the egg at the end of the line.

(Full series here: https://jineralknowledge.com/tag/arkrepro/?order=asc)