the suffering of pregnancy threatens both mother and child

While complications in pregnancy and childbirth used to be among the most common causes of death in young women, these dangers have become less of a threat. However, this does not apply to everyone equally. Preeclampsia, also popularly known as pregnancy poisoning, continues to pose a threat to mother and child. This condition, which affects an estimated 2.5 to 8 percent of all pregnant women worldwide, is characterized by high blood pressure and many other disorders.

Loss of protein in the urine and accumulation of water in the tissues are at the top of this list. In addition, disorders of the coagulation system, kidney weakness, liver dysfunction, neurological symptoms such as headaches and flickering eyes or delayed growth of the fetus can accompany preeclampsia.

Childbirth protects against seizures

Once pregnancy has started, it usually progresses unstoppably. In the worst case, the woman is threatened with eclampsia, an acute life-threatening condition associated with seizures. Then only an immediate delivery can prevent the woman and the child – if it is already viable – from suffering serious consequential damage. It is all the more urgent to recognize the signs of preeclampsia.

If tackled early, the onset of the disease, which usually occurs after the 20th week of pregnancy, can often be averted or at least delayed, thus preventing premature delivery. The drug of choice is treatment with small amounts of aspirin. This reduces the risk of preeclampsia by up to 80 percent – ​​but only if the therapy begins between the 13th and 16th week of pregnancy.

Scientists around the gynecologist and fetal doctor Kypros Nicolaides from King’s College Hospital in London have made a significant contribution to this finding. Given the enormous protective effect of aspirin – which may be due to its anti-inflammatory and blood flow-improving effects – the question has repeatedly been raised as to whether aspirin should not be offered to all pregnant women. This could save you the time-consuming screening tests to prove preeclampsia, so the proponents argue.

Nicolaides and his colleagues, however, advise against prescribing aspirin according to the watering can principle. As they write in the New England Journal of Medicine, the risks of low-dose aspirin therapy are small, but not zero. Therefore, they could not justify a general prescription of the drug during pregnancy. It is better to look for early signs of preeclampsia in all pregnant women.

Late symptoms are often misinterpreted

What has long been common practice in experienced centers and medical practices leaves a lot to be desired elsewhere. Not only a developing preeclampsia, even a preeclampsia that has already broken out is often misjudged, says senior physician Marc Baumann from the University Clinic for Gynecology at the Inselspital in Bern. Patients with milder symptoms in particular would fall through the cracks. A major reason for this is that the milder forms of the disease often appear after the 34th week of pregnancy or only in the postpartum period.

“If a woman complains of headaches towards the end of pregnancy or after childbirth, this can be due to birth-related pain or additional mental or physical stress,” says Baumann. Preeclampsia could also be the cause. Although there is no longer any danger for the child after birth, there is for the woman.

Preeclampsia puts a heavy strain on the mother’s organism, as the gynecologist explains. The resulting inflammatory processes damage the blood vessels in particular. “In the medium and long term, the women affected have an increased risk of heart attacks and strokes,” says Baumann. It is therefore important to regularly check the woman’s blood pressure and, if necessary, the protein content in the urine, even towards the end of pregnancy and during childbirth. In this way, patients with a late onset of the disease can be protected from serious complications.

A protein is missing in the placenta

Preeclampsia is favored by genetic factors, obesity, high blood pressure and possibly an infection with the new corona virus. Exactly how it arises, however, is still largely a mystery. According to tradition, anyone who solves this riddle and finds an effective therapy will receive a dedication above the gates of the University Women’s Clinic in Chicago. Erected around ninety years ago, this place of honor still has no inscription.

However, researchers now know a lot more than they did back then. It has been shown that the term “pregnancy poisoning” is misleading. Because preeclampsia is not based on toxic influences, as was long assumed, but on an insufficient blood supply to the placenta, the food source of unborn life, also known as placenta. The veins in it remain small and thin instead of growing into large-volume blood vessels.

The cause of the shortage of supplies is insufficient amounts of a protein that stimulates the growth of the placental vessels and is called placental growth factor (PlGF). It is not yet possible to say why the placenta of some women releases too little of this protein and whether the defect originates in the mother or rather in the child.

Delicate therapy of high blood pressure

However, as has been shown, the high blood pressure of pregnant women serves an important purpose. It serves to push enough blood through the sparse placental vessels to ensure the fetus is nourished. Doctors are therefore limited when it comes to treating maternal high blood pressure: If they treat it too intensively, the child’s blood supply will falter, but if they allow it to rise too much, the patient may suffer a cerebral hemorrhage in the worst case.

Doctors can tell from early warning signs whether and to what extent a pregnant woman is at risk of preeclampsia. In addition to high blood pressure – especially in combination with an insufficient drop in blood pressure during the night – there are cases of preeclampsia in the family, reduced blood flow in the uterine arteries, obesity, a low level of the protein in the blood that stimulates the growth of the placental vessels, and changes Concentrations of other messenger substances.

In the later course of pregnancy, the ratio of the PlGF protein, which stimulates the growth of the placental vessels, to another protein called sFLT-1 provides evidence of an increased risk of the disease. The sFLT-1 protein intercepts and disables the PlGF protein. The higher the level of sFLT-1, the more likely it is that preeclampsia will occur in the weeks that follow.

“If the quotient of the two biomarkers is below a certain threshold, we can reassure pregnant women with suspicious readings,” says the Bernese gynecologist Baumann, who helped develop this diagnostic guide. “The risk that the person concerned will suffer from preeclampsia in the next two to three weeks and that the child will have to be delivered prematurely is then very low.” For the unborn child, every week in which the maturation process can be completed is a gain, the doctor clarifies.

Genes indicate risk of disease

Maternal gene activity is apparently also suitable for tracking down preeclampsia months before the onset of the disease. This is at least supported by the study results recently published in the journal “Nature” by researchers from the USAamong them Thomas McElrath from Harvard University in Boston.

In order to find out which genes are switched on or off in the run-up to preeclampsia, the scientists determined the RNA molecules in the blood of 72 women who later developed preeclampsia and compared these gene transcripts with those of 452 healthy pregnant women. They discovered that the gene activity of the two groups differed significantly. Seven genes made a significant contribution to this difference: all hereditary factors that play an important role in the development of the placenta and vascular growth.

As further research has shown, genetic fingerprinting can be very useful in early pregnancy. It is therefore suitable for predicting the risk of preeclampsia with comparatively high accuracy, even without knowing the common risk factors such as blood pressure and family history. If the findings of the American researchers can be confirmed in further studies, they could help to identify women with an increased risk of preeclampsia even more reliably than before. However, this works quite well with the means already available – but only if they are actually used.

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