HOUSTON -- Volunteers expanded their search Thursday as they looked for a pregnant woman who has been missing for more than a week, KPRC Local 2 reported.

Tierra Adams, 25, has been missing since her alleged boyfriend dropped her off on the side of North Houston Rosslyn Road near state Highway 249 at about 1 a.m. on Jan. 29.

Adams is nine months pregnant and due to give birth on Valentine's Day.

"There's been too many days for her not to say anything, not call and not anything. Nobody. She hasn't called her sister, no one," Adams' mother, Rose Adams-Itive said. "He (the alleged boyfriend) said they were going on and on in the car, whatever, and he just told her to get out. This was 1 a.m. and he put her out, supposedly in this area."

Adams-Itive said she fears the worst.

"That my child is not going to come back," she said. "She's not going to come back alive anyway. If you're out there alive, Tierra, just please call. That's all. No one's going be mad or whatever. Just call. That's all I'm asking."

Volunteers searched the area on Wednesday and did not find anything. They decided to expand their search area by about five miles and will concentrate on certain areas.

"Under bridges, heavy woods, creeks, abandoned buildings, any place that could disguise the appearance of a body," Texas EquuSearch coordinator Frank Black said. "I'm very concerned for her safety at this point. There's some reasons for me to believe that she's deeply in danger if not harmed already."

Adams-Itive said Neriah Roberts, Adams' alleged boyfriend, told her the two got into an argument after he caught Adams smoking.

Roberts denied being Adams' boyfriend and said he does not know if he is the father of her child. He said he caught Adams smoking either marijuana or PCP at his house.

He claimed Adams put up a fight and said she did not want to go home to her parents because she would get in trouble and possibly have to go back to jail. Roberts said he dropped Adams off when she put up a struggle.

"Just the time she's been around me, she left jail, in and out, three times," Roberts said. "This last time she was in for eight months. I've been doing my best to help her with her drug problems."

Investigators are not calling Roberts a suspect.

"I just can't understand how you can just put a pregnant woman, eight and 1/2 months pregnant at 1 o'clock in the morning. It just doesn't add up," Adams-Itive said.

Adams-Itive denied that her daughter had a drug problem.

"We've called hospitals. She's not there," Adams-Itive said. "They've checked the jail system. She's not in there. Where could she be?"

Texas EquuSearch founder Tim Miller said, "If anybody just thinks they've seen anything, give us a call. We'll follow every lead that we have. She's supposed to deliver this baby in less than one week, so we just can't imagine her being out on the streets this close to delivery time."

Adams is black, 5 feet 6 inches and weighs about 200 pounds. She was last seen wearing white Capri pants and a black and white shirt.

Anyone who has seen Adams or would like to volunteer in the search was asked to call Texas EquuSearch at 281-309-9500.