The happy couple’s first dinner as husband and wife will be a magnificent banquet rich in iron, calcium and complex carbohydrates: the perfect menu for the most chic of shotgun weddings.

During the marriage ceremony, the bride, Wakako Iwatani, will carry a scent-free, low-pollen bouquet up the aisle of the wedding chapel in Yokohama and take her seat — carefully — at a pew with twice the normal amount of padding.

A team of assistants will hover nearby at all times as she exchanges vows with the groom, Keisuke, ready to pounce with iced water if she is overcome by morning sickness.

Everything, from the generously elasticated rental dress to the special anteroom for napping, is part of the “Double Happy” service — once a niche market for pregnant brides, but one that now represents nearly a third of the hugely lucrative Japanese wedding industry. Megumi Takanami, the wedding planner for Wakako and Keisuke, believes the trend will continue to grow.

“From about five years ago the number of dekichatta-kon \ that we handle has not stopped rising,” she said. “Last year we worked out that about a quarter of the brides we worked with were pregnant, and some were about eight months along when they tied the knot.

“The couples used to be embarrassed, and our job was to try to hide the fact from the families. Now everyone is so relaxed about it we try to turn it into a double celebration and make life as easy as possible for the mother-to-be.”

A spokeswoman for Watabe Wedding said that attitudes were similarly relaxed on the southern island of Okinawa. In the past, pregnant brides had often skipped the party and settled for a photograph but nowadays about 30 per cent of brides were pregnant and opted to have a full event.

With pregnancy no longer a bridal taboo, the number of “pregnant and proud” weddings has soared, as have attempts to rebrand shotgun weddings as trendy. In Aoyama, at the heart of Tokyo’s flashy bridal belt, several establishments offer pregnant bride services under the title “Ma marriage”.

The shift reflects changing attitudes in Japan. The historic taboo of pregnancy outside marriage was largely abandoned during the 1990s but a strong tradition of being married by the time of the birth remained.

By 2004 the national average of ten months between marriage and the birth of a first child had fallen to six.

Equally important, social commentators say, is the psychological effect of Japan’s bigger demographic problem. For 28 consecutive years, the country’s population of children under the age of 15 has fallen to a new low. For the parents of young women, that relentless decline has had a profound effect — in a country where fewer and fewer women are choosing to have children, a daughter’s pregnancy and the prospect of grandchildren is hugely welcome.

Rather than pointing the proverbial shotgun at the man who put their daughter in that situation, Ms Takanami says, the parents are often grateful.

Nuptial numbers

— 714,000: number of annual weddings in Japan according to the last census

— £12,000: average amount spent

— 26 and 29: average age of bride and groom

— £127: The cost of hiring a fake wedding guest at an agency in Tokyo. For an extra £64, he or she will give a speech

Sources: 2005 Japanese Population Census, Times database

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