Sweden canceled a major study on women whose pregnancy lasted more than 40 weeks after the death of six babies.
The study was discontinued a year ago after continuing pregnancy until 43 years, with five years of stillbirth and premature death of a female baby.
The researchers concluded, "Our belief is that it is ethically not right for what is going on."
There is no international consensus on how to manage a healthy pregnancy that lasts longer than 40 weeks, but in general, it is common to increase the risk of side effects for mothers and babies in excess of 41 weeks.
But because of the low risk, studies of late pregnancy require a large number of women to achieve statistical significance. Swedish post hoc study (Swepis), led by Sahlgrenska University Hospital in Gothenburg, began a survey of 10,000 women in 14 hospitals.
Women at 40 weeks of pregnancy were invited to participate in the study, unless they occurred spontaneously, randomly divided into two groups, leading to labor at the beginning of 42 or 43 weeks.
When suddenly discontinued in October 2018, the study was only a quarter of the number of target pregnant women. However, six weeks of death has already proved to be a significant increase in the risk of women triggered at the beginning of 43 weeks. In the group that finished pregnancy a week ago, infants did not die.
The findings were reported for the first time by Swedish television in the summer, but the findings refused to release the results or talk to the press until they were published in the medical journal. However, the details are included in a doctoral dissertation recently by one of the researchers available on the University of Gothenburg website.
The immediate results of this study could be “a change in clinical guidelines that recommend inducing labor until late at 41 + 0 gestational weeks,” the author concludes.
Sahlgrenska Hospital announced Thursday that it will change its pregnancy management policy based on the results of the Swepis trial.
"We waited for a scientific analysis. It showed that the risk of waiting more than two weeks is true," said the hospital's maternity director, Swedish television.
"Now we plan to offer induction to all women during their tenure at 41 parking as soon as possible."
Another hospital participating in the study has already changed its policy after the death of two infants. Other Swedish hospitals say they will follow suit.
Sweden's national charity, which supports parents who lost their infants, had to immediately change hospital policies across the country.
Malin Asp, chairman of the Swedish Infant Death Foundation (Spadbarnsfonden), said, "It is very unethical not to disclose in the results after the study has ended for ethical reasons." "It is possible to save the baby's life."
Sara Kenyon, an evidence-based birth management professor at Birmingham University, said that when six babies died in the late pregnancy group, there was a significant clinical and statistical difference between the women in the two groups. She said the findings are "important for practice."
In the UK, the NHS proposes to attract all women who have not started work by 42 weeks. Only 41 out of 5 women give birth after 41 weeks without medical intervention.
Last year, Professor Robert M Silver, co-author of the American study, suggested that it would be appropriate to give women the option to induce early 40 weeks, and the Guardian said that the Swedish findings appear to be "completely consistent."
"If you continue a healthy pregnancy after 40 weeks, the risk of complications is still low," he said. “But the more babies you give birth, the fewer stillbirths you have. Early induction also reduces the risk of cesarean section. ”
Jan Jaap Erwich, an obstetrician-gynecologist at the University of Groningen, the Netherlands, said the Swepis study may be the last attempt to determine the exact effect of late pregnancy. I will study again with many women. ”