For the increasing number of Japanese brides facing the challenge of slipping into a wedding dress in the middle of a pregnancy, a Tokyo rental clothing shop is ready to help with a variety of maternity gowns for the big day.

Joyful Eri in Katsushika Ward will offer three types of maternity wedding dress from January to cash in on the trend.

The firm, which has 15 outlets in Japan, said it came up with the idea because in one out of every four couples it serves at its Shinjuku shop, the bride is pregnant.

"Many women are sixth months pregnant by their wedding day," Shinjuku store manager Yoshie Takenouchi said. The trend was recently highlighted when popular actor Takuya Kimura announced he would end his solo act as his girlfriend, singer Shizuka Kudo, is with child and they are getting married.

Singer Namie Amuro also became pregnant before she tied the knot with her boyfriend. According to demographer Miho Iwasawa, the portion of Japanese women who gave birth within seven months of their wedding reached 15 percent in the 1990s, after 8 percent in the 1970s and over 10 percent in the 1980s.

A 1992-1997 Health and Welfare Ministry survey found that over 10 percent of 1,300 couples had their first children within six months of their nuptials. But unlike Sweden and other Northern European countries, Japan still discourages premarital pregnancy, Iwasawa said.

"As the number of unwed couples increases, Japan is becoming a society with a low birthrate." One 27-year-old Tokyo woman who is six months pregnant wants to have her wedding in February.

"I plan to announce my pregnancy at my wedding," she said. "I think it'll be good for my baby if I break the news cheerfully."