Jennifer Matthews: Motherhood was always in the plans for Laura Stinson.

Laura Stinson: I always knew I wanted to have four. Then, I had two and said, 'That was enough,' and then, we were blessed with two extras.

Jennifer Matthews: Laura can say that today, but when she was pregnant with Sarah, depression set in.

Laura Stinson: I started feeling overwhelmed. Simple things like paying the bills, I couldn't do it.

Jennifer Matthews: Knowing antidepressants pose risks to unborn babies, Laura looked for something different. She found it with two simple clicks.

Doctor Katherine Wisner is involved in a formal study on the power of light therapy.

Dr. Katherine L. Wisner: I've become absolutely excited about the possibility of showing that it's an effective treatment for depression in pregnancy and that we might spare many women medication treatments during pregnancy.

Jennifer Matthews: While doctors don't understand why the light therapy works, doctor Wisner says all that matters is that it does.

Dr. Katherine L. Wisner: The number of patients who respond, and the rate at which they respond, is similar to drug studies.

Jennifer Matthews: 45 minutes every morning was all it took for Laura's mood to turn around, and it took less than three weeks. Even now, when she uses it, Laura notices a difference.

Laura Stinson: I find that I do have a little extra spring in my step.

Jennifer Matthews: And that's important to keep up with the activity of her active crew. This is Jennifer Matthews reporting.