Immigrant rights groups scouring the desert between Mexico and Arizona have lately spotted something disturbing amid the debris left by border crossers -- more and more baby bottles.

Authorities believe it is further proof that more women and children are making the dangerous and illegal trek through the desert, possibly to reconnect with husbands and fathers already in America.

"People are moving on in all senses: more kids, more minors, more women, more indigenous people," said Miguel Escobar, Mexican consul in Douglas, Ariz.

In the Border Patrol's Yuma sector, which covers the southwestern corner of Arizona, the number of apprehensions is up overall. But the number of juveniles skyrocketed to 4,000 and the number of women jumped to 6,500 from October through July. By comparison, only 947 juveniles and 5,362 women were caught in the entire previous fiscal year in that sector.

In the patrol's Tucson sector, which covers the rest of Arizona's border, the number of men caught trying to cross -- about 210,000 -- was roughly the same from October to June, said Frank Amarillas, a spokesman for the Border Patrol in Tucson.

But in that same period, the number of women climbed to 38,000, up from 32,000 the year before, and the number of juveniles rose to 8,000 from 7,000.

Observers say the jump in the numbers may be a reaction to U.S. immigration policies.

In some cases, legal residents have applied to have a spouse or family member come from Mexico, but the backlog can mean years of waiting until they decide to take the risky journey, said Katharine Donato, a sociology professor at Rice University (search) in Houston who studies immigration.

On the other hand, Escobar said more women and children are attempting to migrate north because increased border security makes it difficult for U.S.-based men to travel back and forth, as they had done for holidays, birthdays and other breaks.

"People used to go in some sort of a circle," he said. "They used to work in the states for five or seven months and go back and then come back to the States to work again."

The new reality leaves families divided for long stretches. And despite the dangerous terrain in many sections of the Arizona border, more women and juveniles seem willing to risk the trip.

"If they want to see their families, it's their only option," Escobar said.

The Rev. John Fife, a Tucson pastor who helped organize two immigrant rights groups, has seen the rise in children and mothers making the trip. "It's really accelerated within the last year," he said.

"If men can't go back and forth to Mexico, they are trying to bring their families here to be reunited," he said. "Almost all the women I talk to are coming so they can try to keep their families together."