Human ovulation cues

• Recent research reveals cues of ovulation in women that observers can detect.
• These include attractive changes in women's scents, voices, and appearance.
• Observers respond to human ovulation cues behaviorally and hormonally.
• Nonetheless, it is likely that women have evolved to suppress ovulation cues.
• We outline research questions that will help to address lingering mysteries.

In most mammals, cues of impending ovulation — including changes in appearance and sexual behavior — mark the fertile phase within the ovulatory cycle. Such cues were long thought to have been completely concealed in humans. However, research over the past two decades has overturned this assumption, revealing subtle but detectable cues of ovulation to which observers respond both behaviorally and hormonally. We review research in this area over the last several years. Cues of ovulation in human females include attractive changes in scent, voice, and appearance. Women also appear to be more receptive and solicitous toward sexually attractive prospective mates when fertile within the cycle. We discuss reasons why human ovulation cues are subtle and outline questions for future research.