Between posts about swaddling and liquidy poos, online forums like Mumsnet and Reddit are full of anxious, sleep-deprived parents looking for advice on which infant formula to buy. As formula costs continue to climb — a month’s worth now runs about £89 ($112) in the UK — the pressure on caregivers is only being amplified.

While higher-end brands can go for as much as 70% more than the cheapest formulas, even the more affordable labels are becoming increasingly expensive. In the two years up to last autumn, formula prices rose 25% on average, according to the UK’s Competition and Markets Authority. This week, as part of a broader backlash against excessive inflation of household goods, the anti-trust regulator said it was opening a market study into formula pricing.