If you are a new mother and unable to breastfeed, few places are better than Brazil when it comes to getting assistance. Milk banks, which collect donated breast milk and distribute it to mothers and babies in need, have existed since the early 20th century, but they were frequently expensive and not widely accessible. But in the 1980s, João Aprígio Guerra de Almeida, a young chemist, worked with Brazilian public health officials to redesign the country’s milk banks from the ground up, using cheap, creative solutions like repurposing hot water baths from the food industry that were 10 times cheaper than standard pasteurisation machines, or sterilising coffee and mayonnaise jars so they could be reused as milk bottles.

The Brazilian word for this imaginative problem-solving is jeitinho, says photographer , who, with the journalist Niklas Franzen, visited and reported on several of Brazil’s milk banks, like the Fernandes Figueira Institute in Rio de Janeiro.

Today, Brazil’s milk-bank system is frequently cited as one of the world’s best, providing some of the world’s cheapest and safest breast milk. It operates at a vast scale, with more than 200 milk banks – the most in the world – serving hundreds of thousands of babies. Brazil saw a more than 70 per cent drop in mortality of children under 5 from 1990 to 2015, which credited at least in part to its milk bank system.

On top of its efficiency, part of the reason for the system’s success is that it makes it easy for women to freely donate and receive milk, supported by a network of courier drivers who crisscross the country. One of these drivers can be seen delivering milk by bike in Flamengo, a suburb of Rio de Janeiro (above). “We spoke to one donor, and she said, if it wasn’t for a courier to pick up her milk, she wouldn’t do it, it would just not be possible,” says Bethge. “This would be really nice for Europe and for other countries”, to adopt, she adds.

The milk banks themselves are also multipurpose facilities, acting as holistic support centres for new mothers, collecting milk, sterilising and storing it, as well as supplying it directly to premature babies in need. All milk is first checked for large contaminating detritus, such as hair or dust, that would result in a sample being rejected (above). The milk is then warmed up and liquefied in a water bath (below), so that it can undergo more rigorous tests to ensure that it is free of biological contaminants (main image, top).

Women can also receive assistance from nurses to help express milk for their babies if they are in need, such as in wards for premature births (below).

“You see the whole circle, from the woman who was delivering [the milk] to the baby who gets it,” says Bethge.

The idea that we should make lifestyle adjustments depending on where we are in our menstrual cycle is gaining traction online, as well as in scientific circles. Now, researchers have found that athletes who obtain a sports injury while on their period seem to take longer to recover from it than at other times in their cycle.

#cyclesyncing is tagged in thousands of social media posts that promote altering diet and physical activity levels around the different stages of the menstrual cycle, to adjust for the hormonal changes that occur. The evidence supporting such dietary changes is weak, and while exercise-related studies on this subject are more robust, their results have also been mixed. Nevertheless, rugby union teams in the US and England already .

To try to better understand this, and her colleagues at Hospital Sant Joan de Déu in Barcelona followed 33 professional football players from the FC Barcelona women’s team across four seasons between 2019 and 2023.

As part of their normal training regimen, the women self-reported the days when they were on their period. Any injuries that occurred over the seasons were categorised in terms of severity by a doctor using a standard scale.

The researchers found that although the women didn’t obtain more injuries while they were on their period, the ones they did get during this time appeared to be more severe. For instance, soft tissue injuries sustained during this time resulted in more than three times the number of days of training lost compared with when such injuries occurred at other times.

This may be because oestrogen levels are low during a period. . “The combination of low estrogen, possible iron loss, more intense symptoms [such as cramps] and greater fatigue could contribute to a worse prognosis for injuries at this stage,” says Ferrer.

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However, at McMaster University in Canada points out that we don’t fully understand oestrogen’s role in muscle repair. “The ethos is that estrogen is protective and reparative [for muscles], but the majority of that comes from animal studies and not human trials,” he says. The study also didn’t measure the women’s iron levels or potential confounding factors, such as fatigue.

Ferrer accepts that few injuries occurred overall, with 69 taking place on non-bleeding days and just 11 while bleeding. “A small number of very serious injuries can skew the overall impression if the sample size and confidence intervals are not taken into account,” she says. We also don’t know whether the results apply to those who exercise or do sport more casually, rather than at a professional level, says Ferrer.

Periods are starting younger and we’re struggling to pin down why

Menstruation is occurring earlier and earlier in life for younger generations in the Western world, but researchers are puzzled as to why

She hopes the picture will become clearer with further research, which could lead to bespoke exercise recommendations at different times in the cycle. “The most responsible approach is that decisions regarding training load and type during menstruation should be individualised,” says Ferrer, “taking into account each player’s symptoms and relying on objective data (internal and external load, injury history, well-being, etc.), while research continues to incorporate hormonal measurements, iron markers, sleep patterns, nutrition and other variables that can help refine recommendations.”