WEDNESDAY, May 31 (HealthDay News) — Jennifer Burch has seen the ads for Seasonale, Barr Pharmaceutical’s new packaging of the standard birth control pill that promises users just four periods a year.

But, she said, she’s not buying it.

“Let the body do what it does naturally,” said Burch, a 32-year-old yoga instructor who said she was in the midst of her monthly period at the time, with its usual bothersome mood swings.

“If we weren’t meant to have periods — if for some evolutionary reason that made the most sense and was the healthiest — then we wouldn’t have them,” Burch said from her home in New York City. “I say, let the energy flow.”

Susan Greenhalgh, a 40-year-old chemicals broker from Amityville, N.Y., has also put up with the physical and emotional hassles that come with periods. But, she said, she has her suspicions, too.

“As much as I would love to not be bothered by a monthly period, I can’t believe that manipulating hormones and your body’s natural cycle to that degree could be healthy,” Greenhalgh said.

And yet gynecologic experts say putting an end to the period is safe, and that the growing popularity of interventions such as Seasonale — whose sales jumped 62 percent last year to over $110 million — shows there are a lot of American women willing to take that step.

“I believe that most women would really like to get rid of their period,” said Dr. Camelia Davtyan, an expert in women’s health and assistant professor of medicine at the University of California, Los Angeles, Medical Center. She pointed out that any woman who is on the Pill ceased having a real period long ago, anyway.

“When women are on the Pill and have a period, it’s not a natural period — there was no actual maturation or transformation of the lining of the uterus,” Davtyan said. Instead, gynecologists call it “withdrawal bleeding.” This bleeding only occurs because the uterine lining experiences a sudden drop in progestin during the placebo week, Davtyan explained.

And the Pill’s 7-day placebo “break” was arbitrary in the first place, she added.

“There’s an anecdote that’s floating around the gynecologic world that when the Pill was first introduced 40-something years ago, it was made by a bunch of guy gynecologists,” Davtyan said. “They just thought women would be much happier to have something closer to their natural period, rather than to have no periods at all.”

Dr. Shari Brasner, an obstetrician/gynecologist affiliated with Mount Sinai Hospital, in New York City, said she’s used the conventional Pill continuously — without the 7-day break — for years. She said opting for a life without periods has left her with no regrets.

“I companies have an incredibly busy day, and I was never the kind of woman who, quite frankly, had a rigid enough schedule that I could remember to go into the bathroom and deal with issues involving periods,” Brasner said. “I did it on the basis of understanding what the pills were and believing that they were safe.”

Indeed, gynecologists have been prescribing “continuous” birth control pill regimens for decades to help women struggling with problems such as endometriosis. And, Brasner said, new products like Seasonale simply stretch the number of days women take the active pill.

In Seasonale’s case, women take the hormonal medication for 12 weeks at a time with a one-week placebo break 4 times per year, when the user experiences “withdrawal bleeding.”

“And that placebo week, quite frankly, was only added to just be more acceptable to the user,” Brasner said. “The concept of going from 12 or 13 periods per year down to none was a huge [mental] leap, so they’ve tried to soften that by still giving women that occasional withdrawal bleeding.