Translator: Denise RQ Reviewer: Lena Clemente
In a few days time,
we'll be commemorating Armistice Day
In remembrance of the millions of lives lost 100 years ago,
in the First World War.
This year, over 300,000 women will die in childbirth.
That is more maternal deaths
than allied soldiers lost during the First World War each year.
The majority of maternal death
is due to infection or bleeding at the time of childbirth,
and the cost of preventing these deaths
is that of training
expert birth care attendants and organizing health care.
Thankfully, the World Health Organization
and other partner institutions have worked relentlessly,
and maternal death has decreased by over 40% in the last 20 years
to the levels that it is now.
Today, I'd like to talk to you about pre-eclampsia,
a condition responsible for one in five maternal deaths.
That's a maternal death every 12 minutes somewhere in the world.
Pre-eclampsia is a complication of pregnancy
that results in very high blood pressure.
As a trainee obstetrician,
your first encounter with pre-eclampsia can be quite traumatic.
A perfectly healthy mother comes to our maternity unit
accompanied by elated relatives, expecting and primed for a happy event.
The midwife puts on a blood pressure cuff as routine.
But within minutes,
you can see from her expression that things are not right.
Her blood pressure is sky high
and despite our best attempts to control it,
she becomes severely ill,
and both her and her baby are admitted to our intensive care unit.
In many countries in the world, they would both have died.
It's left to me to explain
why this catastrophe has occurred.
All I have, by way of explanation,
is the same story that doctors have been repeating for 100 years,
and that story suggests
that something abnormal in the development of the placenta
caused her high blood pressure to occur.
It's that story that I'd like to explore with you today.
Pre-eclampsia was first described in 500BC,
and the medical features of the condition clearly documented about 100 years ago.
That documentation firmly believes
the placenta is central to the causation
because you have to have a placenta to develop pre-eclampsia.
The finding of tiny cellular lesions in the placenta, down a microscope,
and the fact that the baby grows poorly in pre-eclampsia,
support the placental hypothesis.
Presumably, the placenta can't feed the baby as well.
Also, the fact that delivery of the placenta cures pre-eclampsia
is taken as irrefutable evidence that the placenta causes pre-eclampsia.
I've been an obstetrician for over 25 years,
with a research interest in pre-eclampsia,
research that is embedded in the belief - or at least, it was initially -
that the placenta causes pre-eclampsia;
something that I have begun to regard with a different perspective;
a perspective that challenges
the prevailing medical opinion and beliefs.
We first realized things were different when we started to look
at how the mother responds in pregnancy.
We found that most women did not have anything wrong
with their placenta,
and in fact, their babies were normal in size or even larger than average.
Those don't fit with the placenta working poorly,
but what we could not take away
was the fact that you have to have a placenta to develop pre-eclampsia,
and that delivery of the placenta cured pre-eclampsia.
That seemed to be irrefutable until our research
on the long term health of our women,
and that showed some interesting findings.
Women who develop pre-eclampsia are five times more likely to develop
heart disease or stroke in the subsequent 20 to 30 years.
In fact, two out of three women who develop pre-eclampsia
will die from heart disease.
Here's a thought:
how does the placenta that we disposed of 20 years ago,
have such a profound and serious effect on the mother's heart?
The problem with pre-eclampsia
is that we really didn't know how to analyze this effect,
and it seemed a conundrum.
Taking the placenta away cured the disease,
but yet, predisposed to long term problems.
That seemed difficult and confusing
until I started to see parallels with another disorder in pregnancy,
the disorder called gestational diabetes,
where a mother develops diabetes as a consequence of the pregnancy.
The mother's pancreas is unable to deal with the sugar load of pregnancy
and can't produce enough insulin - the sugar-controlling hormone -
and therefore, diabetes occurs.
Interestingly, diabetes in pregnancy
is cured by the delivery of the baby.
What's more, women who develop pregnancy diabetes
have a 50% risk of developing diabetes themselves
in the 10 years following pregnancy.
I don't know about you,
but it seemed logical to me to consider the possibility
that pre-eclampsia had nothing to do with the placenta
but that pre-eclampsia represented a condition
where the mother's heart was unable to deal with the vascular load of pregnancy.
St. Georges University of London, where I work,
has a renown sports cardiology center.
A multi-disciplinary team headed by professor Sanjay Sharma
monitor and help our elite cyclists, rugby players, Olympians
achieve their best performances,
and they have all the best medical technologies available to them.
They're particularly interested in the performance of the heart.
For example, did you know
that a young elite athlete who is setting out on a training program
will increase the weight of her heart by 25% over a two-year period?
Picture a pregnant mother.
By nine months of pregnancy, her heart mass has increased by 40%.
Look at the little grooves in the heart, those grooves are called trabeculations.
The number and the depth of these grooves
are related to the amount of exercise you undertake.
Here is a graph showing the prevalence of trabeculations
in various elite sportsmen.
And where do you think pregnancy comes there?
Take a guess. Off the scale.
So yet again, pregnancy out-performs our best and most elite sportsmen.
To understand this, you need to realize
that an Olympian may exercise for 10 hours a day, five days a week but rest.
A pregnant mother is working, 24 hours a day, 7 days a week,
for 9 months and increasingly so, as time goes on with no rest,
even when she's sleeping.
And therefore, you've got to acknowledge that this is a truly Olympian achievement,
and pregnant women are mothers, are partners
also deserve our respect for this.
We are not all Olympians,
and therefore,
it should come as no surprise to you
that about 10 to 15% of women
struggle to cope with the vascular load of pregnancy;
their heart comes under considerable strain.
Evidence for this comes from
reviewing the symptoms of pregnancy.
Those of you who've been pregnant will recognize some of these symptoms:
shortness of breath, swollen ankles, etc.
I'm not getting much acknowledgment for the last one on the list,
perhaps I should ask your partners.
Is it just a coincidence
that the symptoms of heart failure are exactly the same?
When we look at the heart function in women who have pre-eclampsia,
we find that it's quite deranged
in the same way that pancreatic function is deranged
in women who develop diabetes in pregnancy.
In fact, in most severely ill pre-eclamptic women,
the heart function is similar to that of a 70-year-old woman.
We followed these women up for one to two years
to chart their recovery,
and were quite surprised to find little if any recovery over those 2 years.
And that was shocking.
So the question remained,
what is the effect of pre-eclampsia on the mother's health?
In order to tackle this, we developed a collaboration with Doctor Heather Boyd
in the Statens Serum Institut in Denmark,
and we followed up the postpartum health of a million Danish women.
What we found was that 20-year-old women who developed pre-eclampsia
had the same risk of developing high blood pressure
as a 40-year-old woman who had a normal pregnancy.
Pre-eclampsia appeared to advance
your age-related risk for heart disease by 20 years.
It now seems totally absurd to me that I went around for 20 years saying
that age, and obesity, and ethnicity were all risk factors
for poor placental development,
and then pre-eclampsia,
when it is obvious to us all
these are all risk factors for heart disease.
If it's so obvious to us all, why did we miss it?
In order to understand that, you need to understand
the relationship between the heart and the placenta is very similar
to the relationship of a pump and a radiator.
For the radiator to work, it needs hot water pumped through it;
and for the placenta to work properly,
it needs the heart to pump oxygen and nutrients through it.
And if the heart is not working properly,
the placenta, which is a very oxygen rich organ,
will send out signals
that makes the heart work harder and increase the blood pressure.
The problem has been for us
that when we looked into and wanted to investigate pre-eclampsia,
we were left looking at the radiator,
at the placenta, and guess what?
The pump had gone home with the mother.
So what conclusion could we come to
other than pre-eclampsia is a placental disorder?
Because we simply failed to look at the pump.
I hope you'd agree that the evidence for the heart being involved
and the cardiac origins of pre-eclampsia are quite over-whelming.
Yet, we need to try and understand
why the scientific community
are finding it difficult to grasp this ideology.
There I must admit to being culpable, as well.
For many years, I was a believer in the placental origins
and suffered from something called confirmation bias,
that is a tendency to search for and interpret evidence
to support my prior beliefs.
After all, we're asking them to throw away
what they have believed is the unshakeable truth for 20 years
and accept a new paradigm.
It's even worse when you challenge a researcher or colleague
and say that they have misinterpreted the evidence for 10 to 20 years.
That insights anger and rejection.
It's far easier for me to collude with them
and say that actually we haven't got much evidence,
and that's why we haven't made any progress.
And most important of all, research funding drives our research
and funding applications for money are reviewed by pre-eclampsia experts
who believe in the placental origins
and are less tolerant of other hypotheses.
For example, a US institution recently awarded over 50 million dollars
looking at placental health in disease;
good luck with that.
Where do we go from here?
Understanding a disease is vital
whether it's pre-eclampsia, or anything else,
to help us cure and help.
In pre-eclampsia, a diagnostic test is blood pressure -
technology that is 150 years old.
I've seen a woman
come to clinic in the morning with a normal blood pressure
and be admitted later on that day with seizures from pre-eclampsia.
It's this inability to diagnose pre-eclampsia in a timely fashion
that leads to women dying in a rural setting
because they haven't got time to access healthcare.
And only by understanding the disease can we begin to work on
appropriate diagnostic tests that give us time.
Our treatment for pre-eclampsia is scheduling birth.
Pre-term birth, being born early,
is the leading cause of death under the age of five -
a million deaths a year.
It's not until we understand and accept the cardiac origins of pre-eclampsia
that we will begin to even scrape the surface
of a treatment or prevention for the disease.
Every women has the right to safe childbirth.
I fear that until the scientific community understands and accepts
the cardiac origins of pre-eclampsia that we will make no progress
in reducing death and disease due to pre-eclampsia.
What I hope is that we, doctors and scientists, could be
a little bit more open minded and see things from a different perspective,
as you have done today.
Thank you.
(Applause)