WASHINGTON - A study showed that young women are more likely to experience sleep disruption in days leading up to their menstrual period.

The study presented on Saturday at an annual meeting of the Endocrine Society in US New Orleans showed that menstrual phase could affect sleep efficiency, wake after sleep onset (WASO) and number of awakenings per night.

"Sleep is more disrupted in the several days directly prior to menses in young healthy women," said Anne E. Kim, a medical student at Case Western Reserve University, who led the study.

Compared with the early follicular phase, sleep efficiency decreased by 3.3 percent, WASO increased by 15 minutes, and number of awakenings per night increased by three in the late luteal phase, according to the study.

According to the National Sleep Foundation, 25 percent to 33 percent of menstruating women in the United States have reported more disrupted sleep during the weeks before and/or during menses.

The researchers collected daily sleep data from 10 healthy women between the ages of 18 and 28 who had regular menstrual cycles. They wore sensors on their wrist to record sleep patterns over 578 sleep episodes and provided morning urine samples for hormone analysis.

The researchers said those effects might be mediated by the dynamic changes in ovarian hormones across the menstrual cycle.

The study found that the hormone called E1G was linked with more awakenings, and another hormone called PDG was linked with a trend toward higher sleep fragmentation index.

"These findings suggest that women need to be particularly cognizant of practicing good sleep hygiene in the week before menses and with decreased caloric intake," said Kim.