In Iron Lady, Meryl Streep shows us how hard Margaret Thatcher worked to become Prime Minister of England. That hard work included lowering her voice tone.

Her handlers told her that no one wanted to listen to–let alone be led by–a “screeching woman.” They also told her to ditch her pearls. And while Thatcher kept the jewelry, she did work with a voice coach to lower her tone.

In fact, two recent studies focus on the value of lower-pitched voices. One study found that voters rated lower-pitched speakers higher for leadership potential, honesty, intelligence and dominance. The other study suggested that people–both men and women–with lower voices do better at attracting the opposite sex.

So, lowering your voice tone can mean reaching the corner office and finding someone interesting to dine with! I often work with women executives to use the lower range of what’s natural for them. Here are my top three tips:

1) Recognize your range. Women have a greater pitch range than men, which means they are less likely to be monotone but more likely to hit squeakier octaves. I will tape clients when they don’t realize it to illustrate their range. Clients also see that a higher pitch is often connected to nerves. When they’re in the spotlight, everything, including vocal chords, constricts.

2) Relax. Breathe deeply, lower your shoulders, and loosen up before you start to speak. A Columbia University study suggests that tight body language before your perform leads to a less confident performance.

3) Rehearse right. As you practice your presentation out loud, place your fingers lightly against your throat. You’ll feel your vocal chords rise and fall with your pitch and you’ll be able to monitor your own progress.

If you want to lower your voice tone, know that it requires work over time. But for those who have the Iron Lady’s will, it can pay off.

Here’s a clip of Iron Lady, which opens for limited release Friday:

http://www.youtube.com/watch?v=hZrAKdlX0SA