Through prayers and free ultrasound, a bus in Houston, Texas, has been helping pregnant women rethink their choices right in front of an abortion clinic, thus saving lives of many unborn children in the process.

Take for instance Richelle Scott. She went one day to Houston's Planned Parenthood clinic intending to abort her second child as she was concerned about not being able to afford to raise the baby.

Before making the decision to end the life of her unborn child, Richelle connected with prayer warriors from Houston's Coalition for Life on a sidewalk right in front of the abortion clinic. The prayer warriors invited her to a bus, which offers free ultrasound and pregnancy tests.

After seeing the life of another human being inside her through the ultrasound bus, Richelle decided not to proceed with her abortion.

"As soon as I saw him on the ultrasound and they let me hear the heart, I started crying. That was it," Richelle shared.

Today, the baby boy she decided to keep, Alan, is the source of her joy.

For the past four years, more than 7,000 women like Richelle have stepped on the bus, and nine out of 10 of them have decided not to push through with abortion after being given free ultrasound and counselling.

For veteran sidewalk counsellor Nancy Shaw, it is important that people like her and facilities like the bus are readily accessible to pregnant women thinking about abortion.

"It is so important. It's so easy to say, 'Honey, we have help right here, right behind you in the bus. Right here, right now," Shaw said.

Christine Melchor, executive director of the Houston Coalition for Life, said the free ultrasound, which allows the pregnant women to see the unborn children inside them, literally spells out the difference between life and death.

"They usually start crying as we begin and cover their eyes. As we continue with the ultrasound they start peeking out with their fingers," Melchor said.

"We call it a baby and we call them mom and 'Oh, look—he's sucking his fingers and he has the hiccups' and the next thing we know they're smiling and crying at the same time," she added.