Browsing sewing pattern books at the Jo-Ann Fabrics & Crafts store in Kansas City, Mo., Mary Ann Heston worries about whether she'll soon have as many clothing designs to choose from.

A steady drop in home sewing over the past three decades is prompting changes in the market for sewing products. The latest sign is a merger between the No. 2 and No. 3 sewing pattern companies — McCall Pattern Co. and Butterick Co.

The move will leave the combined company with only one major competitor, and that makes Heston nervous.

"It's comforting to come to a fabric store and sit down at a table and have a variety of pattern books to look in," the 53-year-old homemaker said. "When you get down to a few books, you don't have many choices."

McCall and Butterick are the oldest U.S. makers of sewing patterns, an industry that took off in the 19th century.

In fact, Ebenezer Butterick's timing couldn't have been better when he used his tailoring scissors in 1863 to fashion tissue paper into the first sewing patterns in different sizes. At the same time, sales of inexpensive sewing machines, made by inventor Isaac Singer's fledgling company, were soaring nationwide.

Within a few years, Butterick was taking orders from across the country for its clothing patterns for men and boys. In 1870, Scottish immigrant and tailor James McCall introduced his own dress patterns.

For the next century, the two New York-based companies competed fiercely as they rode a nationwide sewing boom fueled by home education classes that required high school girls to learn to sew.

But the good times for pattern makers changed in the 1970s as women increasingly entered the work force and had less time to sew. In March, Butterick and McCall announced they will merge — leaving the combined company with only one major U.S. competitor, Simplicity.

Robert Hermann, McCall president and chief executive, said the merger is a simple matter of survival. Butterick, which also makes the Vogue line of patterns, was losing market share and at risk of going out of business.

Although McCall will still make Butterick and Vogue patterns, the combined company will save money by cutting overlapping administrative costs and closing Butterick's pattern production plant in Altoona, Pa.

Hermann declined to provide sales figures for the two privately held companies, but estimated that the entire pattern industry generates $300 million in annual sales.

At Sew Brooklyn in New York, a small sewing and fabric store where children come in for sewing lessons after school and adults take classes in the evening, owner Jari Anderson is worried about the merger.

Anderson, who opened her store eight years ago, said she's seen a decline in the quality of "notions" — buttons, zippers, thread and sewing materials such as needles — that she attributes to industry consolidation.

The head of Jo-Ann Stores Inc., the country's top fabric retailer, says he had similar thoughts about the merger at first. The company doesn't make a lot of money from the 14 million patterns it sells annually, but they draw customers into Jo-Ann's 1,049 stores in 49 states.

"In a traditional world you believe that more competition is good," said Jo-Ann president and CEO Alan Rosskamm.

Hermann, who will lead the combined company, said that won't happen.

Because of worsening business conditions, "Butterick substantially cut back their new patterns, but we're going to build that back and the consumer will benefit," he said.

The combination with Butterick came about after plans fell through last year for McCall to be acquired by Conso International Corp., the owner of Simplicity patterns.

But federal regulators opposed that combination, saying a merger of Simplicity and McCall would have stifled competition by creating a company with 72 percent of the pattern market. The companies canceled their merger plans.

McCall met with no opposition from the Federal Trade Commission after proposing its new plan to acquire Butterick under a "failing company" argument that Butterick would be forced into bankruptcy without the merger, Hermann said.

The combined company will have 53 percent of the pattern market, according to FTC figures.

The future of the pattern industry is directly linked to the popularity of sewing itself. Rosskamm thinks the business may get a boost over the next decade or so, as baby boomers who learned sewing in school have more time on their hands.

But the only long-term solution is to encourage more young people to use some of their valuable leisure time for sewing.

Lisa Ramsey, a 32-year-old hairdresser from Columbia, S.C., says sewing is a relaxing hobby that allows her to make clothes that fit her better than what she buys off the rack. She thinks the combined company will be smart enough to maintain the Butterick lines.

"If the prices go lower, I'm happy," she said. "If they go higher, they go higher."

But Heston, the homemaker shopping for patterns in Kansas City, remains wary of the merger's impact.

"There are already fewer and fewer people sewing, anyway, and more and more stores are closing," she said. "We have an art and we're afraid our resources could be taken away."