A new study commissioned by media planning agency PHD has revealed the dates, times and occasions at which U.S. women feel "most vulnerable about their appearance."

Marketers find this to be useful info because it will allow them to pinpoint the exact right moments to target female consumers.

According to the survey, 46 percent of women feel least attractive on Mondays, followed by Sunday with 39 percent of women's votes.

Women feel the best on Thursdays, "as the workweek is winding down and they are emotionally preparing for weekend socializing."

As for specific times of day, women feel that they look the worst between 5 a.m. and 7 a.m.; second worst is 1 a.m. - 5 a.m. Gals feel the most beautiful and confident between noon and 3 p.m.

The women polled reported feeling most unattractive while waking up (69 percent), when sick (67 percent), sweating (62 percent), stressed (61 percent), crying (60 percent), and the end of a long day (54 percent).

Psychologically, women feel ugliest when we're depressed, angry, worrying, and lonely.

Here's the marketing strategy PHD has devised:

Monday becomes the day to encourage the beauty product consumer to get going and feel beautiful again, so marketing messages should focus on feeling smart, instant beauty/fashion fixes, and getting things planned and done. Concentrate media during prime vulnerability moments, aligning with content involving tips and tricks, instant beauty rescues, dressing for the success, getting organized for the week and empowering stories.

See lots more on this study's findings in Ad Week.