First there was the baby shower, then came the gender-reveal party. Now parents-to-be are embarking on a new way of celebrating imminent parenthood: the “mother blessing”.

Unlike other baby events, where the emphasis is on gifts for the newborn, these gatherings are focused on nurturing the mother-to-be and wishing her love and luck. Controversially, they are said to derive from the Navajo tradition of “blessingway” – and have been condemned as cultural appropriation.

Less controversially, they involve henna and are perfect for displaying on Instagram.

“It is about honouring the mother’s journey and gathering a group of female friends who are offering their support instead of giving gifts,” said Sue Boughton, a doula, or birth coach, from London, who thinks mother blessings are becoming increasingly popular as people look for an alternative to commercialised baby showers. “Many new mothers feel isolated, and this is about promising to give them time and energy.”

At Danni Ferreira’s mother blessing, five friends wrapped cords round their wrists in a circle, tied string around a candle and made cards with affirmations on them. “One that stood out to me was to trust my body,” said the 35-year-old from Wakefield. “It felt empowering. It was more of a celebration than a baby shower. Getting together and supporting each other feels like a feminist thing to do. It was a good build-up to the birth.”

Connie Tu is one of a growing number of henna artists who can be hired to decorate the pregnant woman’s belly at these events. She says the format varies: “I have seen the expectant mother receiving a ‘food train’ – a list of friends who take turns to deliver food to the house after the baby arrives – and ones that are a simple gathering of close friends,” she said.

Fran Green, 37, from London, has been to three mother blessings in the past year. At the most recent, the friends sat round in a circle and shared food. At the beginning of the ceremony, everyone introduced themselves by giving their mother’s and grandmothers’ names and wished their friend a calm and peaceful birth. Then they read a poem and painted her arms. “We were going to massage her feet in oil but she didn’t want that,” said Green. “She said she’d got a rash.”

One explanation for the trend is that families want to acknowledge life transitions such as births, marriages and deaths, but with a personal twist. “From wedding vows that couples write for each other to eco-funerals, it’s about stepping away from religion, but still signifying certain values to others, such as, ‘we are eco, we are spiritual and we are original’,” said Charlotte Faircloth, a sociology lecturer at University College London.

Social media platforms have also helped to spread the word. With flower crowns, painted bumps and floaty dresses, the ceremonies photograph well: there are tens of thousands of pictures posted under #motherblessing on Instagram. Some even hire professional photographers to document the occasion.

Despite the avowed intentions of some young mothers to eschew commercialised baby showers, experts say that businesses are cashing in on the new trend. Doulas charge around £250 to perform the ceremonies and some involve costly flower displays and other expensive decorations.

But Caroline Gatrell of Liverpool University Management School says high expenditure is not necessary. “Some remain simple in form, with attendees contributing food and, where possible, flowers from their gardens. The point of the blessing is a chance for close friends and family to shower the mum with good wishes. It does not need a doula to organise this,” she said.

Jen Harvie, professor of contemporary theatre and performance at Queen Mary University of London, thinks participants need to be careful when replicating traditionally spiritual ceremonies. “There is a lack of understanding, and it is cultural appropriation,” she said. “On the one hand, there is this fantasy of decommercialising the baby shower but, on the other, [Navajo culture] is being commercialised in a different way.”

Her advice is to imagine your own ceremony, based on your own values. “Use things from your own cultural background,” she said. “Just think about that.”