Biotech, in brief

Researchers in Denmark examined 302 baby girls at about three months old. Their mothers' use of paracetamol, the painkiller sold as Tylenol in the US, had been tracked through pregnancy. [1][2]

Paracetamol is the drug pregnant women take most often. [1]

Girls exposed in the womb had, on average, 40% smaller ovaries, 23% fewer follicles (the sacs that hold immature eggs) and 13% smaller wombs. [1][2]

Girls first exposed before week 17 of pregnancy also had less anti-Mullerian hormone, a hormone that signals how many eggs the ovaries hold and how good they are. [1]

Higher doses went with bigger differences, and no mother took more than the daily maximum of 4,000mg. [2]

Most of the mothers took it for headaches or muscle and joint pain, not for fever. [1][2]

In a second group of 1,210 girls born in Copenhagen between 1997 and 2002, exposure in the womb went with smaller ovaries in adolescence. [2] The same group had smaller wombs at puberty. [1]

A girl is born with all the eggs she will ever have, so her egg supply is set before birth. [1]

Baby boys whose mothers took paracetamol had smaller testes on average, in a second paper accepted but not yet published. [2]

The study cannot prove the drug caused any of this. The illness that led a mother to take it, or chance, could explain the link. [2]

Nobody can yet say whether these girls will have lower fertility or reach menopause earlier. Finding out needs many years of follow-up. [1][2]

Guidelines still recommend paracetamol for pain and fever in pregnancy. The study's leader says a high fever or severe pain left untreated carries its own risks. [1][2]

Why it matters. The next evidence is the paper on the boys, and whether anyone follows these girls to the age when their fertility can actually be measured. [2]

A US trial called Baby's First Years gave mothers on low incomes either $333 or $20 a month, decided by chance, starting shortly after their baby was born. [3] The larger gift added about $4,000 a year, roughly 18% of family income. [3] At age four, children in the $333 group scored slower on DunedinPACE, a DNA test on saliva that estimates how fast the body is ageing. [3] The difference was small, and the mothers' own tests did not change. [3]

Why it matters. Because the gifts were handed out by chance, the difference comes from the money and not from other things that go with being poor. [3] The payments ended after each child's sixth birthday, and nobody knows yet whether the difference lasts or affects health. [3]

Medicare is the US government's health insurance for older people. The Trump administration says tying what Medicare pays for drugs to 19 other rich countries would save $26 billion over several years. [4] It is setting up two pilot schemes, GLOBE and GUARD. They make drug companies pay extra rebates when a medicine costs more in the US than the lowest figure among those countries. [4] A new analysis reported by STAT says confidential deals with more than two dozen drug companies could cut those savings by as much as 80%. [4]

Why it matters. If the analysis holds, Medicare would save far less on drugs than the Trump administration announced. [4] The detailed rules for both schemes are due shortly. [4]

Our Future Health, a UK study that aims to sign up 5 million adults, has published a first look at 1.9 million of them in the journal Nature Medicine. [5] More than 2.5 million people have registered since late 2022, making it the largest study of its kind. [5] Its members broadly match the UK by age and sex, but only 13% come from the poorest fifth of areas, against 20% nationally. [5] They reported more depression and anxiety than national figures, and fewer lung cancers. [5]

Why it matters. About 4.5% of the people invited agreed to join, so the authors say the study should not yet be used to work out how common diseases are across the country. [5] They also suggest long waits for NHS care, Britain's public health service, may have drawn in people with health problems that were not being treated. [5]

Scientists at the Wellcome Sanger Institute in England read the DNA of healthy gullet lining from 70 people who had surgery for gullet cancer. [6][7] By age 60 to 70, almost every cell in a healthy gullet carries some mutations, and most never cause cancer. [6] In patients given chemotherapy with radiation, cells with mutations in TP53, a gene that normally stops damaged cells growing, had spread further. [6][7] After chemotherapy alone, cells with mutations that help them survive the drug 5-fluorouracil had spread. [6][7]

Why it matters. The team says a few weeks of treatment can change a pattern of cells in a healthy organ that took decades to form. [6] Reading healthy tissue like this could help explain why some patients get side effects from cancer drugs. [6]

Researchers used the Mexico City Prospective Study to ask whether differences between ancestry groups come from genes or from surroundings. [8] They measured ancestry and 15 traits in 52,583 unrelated people and 39,714 relatives from 17,627 families. [8] Comparing relatives removes the link between ancestry and home life that confuses comparisons between whole groups. [8] Within families, more Indigenous American ancestry still went with shorter height and a higher risk of type 2 diabetes. [8]

Why it matters. Across the whole population, ancestry also went with years of schooling, but that link disappeared inside families. [8] That points to surroundings, not genes, as the cause of the schooling gap, and to a real genetic part in height and diabetes. [8]

About 9 in every 1,000 babies born in India have a heart defect, some 180,000 to 200,000 a year. [9] A study in the journal Pediatric Research used Global Burden of Disease figures, a worldwide set of health estimates, from 1990 to 2021. [9] India had about 1.5 million of the world's 8.6 million infant deaths from heart defects over those years. [9] Newborn deaths from heart defects fell 1.5% a year in India, against 2.2% worldwide. [9]

Why it matters. Progress stalled from 2003 to 2013, then sped up nearly threefold from 2019 to 2021. [9] The authors put the economic loss from these deaths at $11.7 billion in 2021, and found large gaps in progress between parts of the country. [9]

Nicole Grunstra of the University of Vienna and Jonathan Wells of University College London reviewed birth records for 140 mammal species. [10] Difficult labour was more common with male babies in humans, cattle, water buffalo, sheep, goats, captive antelope and Asian elephants. [10] Earlier work found mothers of boys in Nepal had an 18% higher chance of blocked labour. [10] Their idea is that mothers send more energy to sons in the womb, so the babies grow bigger. [10]

Why it matters. About 700 people die giving birth every day around the world, and a baby's head too big for the birth canal is a leading cause. [10] The authors found little data on wild animals, and one outside scientist says they may be reading too much into what they found. [10]

The European Innovation Council, an EU fund for risky new technology, is opening a 32 million euro call for research on healthy ageing. [11] The money is meant for five to eight projects, each lasting five years. [11] The EU expects the share of its people aged 85 and over to double from 3% to 6% by 2050. [11] Lifespans have grown, but the years people live in good health have not grown as fast. [11]

Why it matters. The grants go to early ideas, meant to show that an approach to keeping people healthy for longer can work at all. [11]