‘CSI’ recollections and the obstetrical dilemma

When my wife and I were newly married, our favourite show to watch was the original CSI series.

Unfortunately, she would fall asleep 10 minutes from the end and the next day I would have to summarise the end for her.

The very unusual lead figure in this show was Gil Grissom, a forensic entomologist, who led his team of investigators and scientists to find the causes of unnatural deaths and eventually to prosecute the offenders.

When a severely decomposed body or skeleton is found the forensic pathologist and his team use a variety of methods to determine the sex, age, race and eventually the identity of the deceased.

This can be deduced from basic things like the bony pelvis and dental records to advanced technology like DNA testing.

The male pelvis, called android, differs significantly from the female or gynaecoid pelvis.

As the female is designed to deliver a baby, the pelvis is wider and more open compared to the typical narrow, heart-shaped male pelvis.

It is estimated that we evolved to bipedal locomotion, walking on two legs, about five million years ago.

For better and faster movement away from predators, we had to have our legs close to each other.

Animals that walk or stand on two legs have the luxury of carrying a larger head, with its obvious advantage of greater brain capacity.

The evolution in head size is thought to be limited by the space offered by the smaller pelvis.

This is called the obstetrical dilemma and is not quite unique to humans as many encephalised primates suffer difficult labours with a high risk of poor outcome.

Squirrel monkeys have a 50% stillbirth rate related to obstructed labour.

Though non-human primates have been noted to have social births with companions involved, only humans have developed assisted birth through midwives and other medical professionals.

It must be stated that the obstetrical dilemma has been challenged by more recent anthropological data.

The variation in the female pelvis in different geographical regions varies widely and seems to be affected by climate, latitude and many genetic factors.

If there was a perfect pelvis for birth, running and carrying body weight it would most likely have developed universally.

The rise in birth weight and head size of babies can also be due to improved nutrition and can be linked to improved agriculture through the ages.

A mother born and raised in a time of general poverty and unavailability of regular fresh food may have a child 30 years later in a world with significantly improved nutrition.

The human brain is developed about 29% complete at birth, compared to 39% for chimpanzees and 50% for most monkeys.

It has been theorised that human gestation has been shortened or compromised to compensate for the ever-growing head circumference.

This then results in the birth of a vulnerable infant that is completely dependent on its mother for months and even years to come.

An alternative theory is that we deliver babies at 40 weeks, not because of head size, but because the mother reaches the limits of providing the nutritional requirement the rapidly growing foetus demands.

Lengthening the pregnancy would severely compromise maternal health and both would suffer.

The medical fraternity has been accused of changing the natural process of birth into a disease and over-managing it.

This then culminates into a high caesarean rate with higher costs and complications.

The newborn is often delivered early which has many negative effects and the mother often has a worse birth experience.

Unfortunately, the birth process is hazardous in a significant number of cases.

The number of high-risk pregnancies are on the rise.

We are seeing an unprecedented rise in obesity, diabetes and hypertension in our reproductive population, and women having children at an older age.

The World Health Organisation has calculated that the optimal rate of caesarean birth is between 10 and 15%.

At lower rates (seen in resource-scarce countries) neonatal outcomes may worsen and at higher rates, there is no improvement in outcome with potential detriment to maternal health.

One of the worse complications seen in countries with a low caesarean rate is birth-related fistulas.

In these cases prolonged labour allows the foetal head to crush the bladder or rectum, causing tissue death, and a channel develops linking the vagina and bladder or rectum.

The poor patient is then rendered permanently incontinent and needs specialised surgery to repair the defect.

The foetus will most likely be born as a stillbirth or have cerebral palsy.

The Hamlin fistula hospital was opened in Addis Ababa in 1974, dedicated to treating these birth injuries.

They have treated more than 50,000 cases thus far.

It is estimated that two-million women worldwide live with untreated fistula.

One thing I have learnt as an obstetrician is that it is very difficult to predict successful labour.

I have j been proven wrong multiple times.

I have also promised women quick and easy labours based on their previous deliveries, and ended up with egg on my face and doing a caesarean for their 5kg baby.

Shakira sang “the hips don’t lie” but I suggest we don’t judge women by their hips, but give them an honest chance of delivering in the manner they prefer.

Dr T is a registered medical practitioner in Nelson Mandela Bay.