Sexual desire, which people commonly refer to as horniness, may change throughout the month. Hormones relating to the menstrual cycle fluctuate over time, which often increases or decreases a person’s libido.
People may experience fluctuations in sexual desire throughout pregnancy, too. The environment can also play a role in influencing libido, with some people feeling hornier during the weekend.
This article explores some of the reasons why sexual desire in females changes throughout the month.
Sex drive in females can change throughout the month for a variety of reasons, including:
The authors of a 2015 review observed that females tended to initiate sex more and showed greater interest in sex just before ovulation. They estimated that a midcycle peak in estrogen occurs about 24 hours after ovulation.
According to the review, scientists believe that estradiol, one of the three types of estrogen hormone, increases sexual arousal in females.
The fact that postmenopausal females who report a lack of sexual desire have lower levels of estradiol circulating in their blood supports this idea.
Second trimester of pregnancy
As hormone levels change vastly during pregnancy, different people may experience different levels of sexual desire.
According to a 2020 study, some hormonal changes may cause people to desire more attention and affection from their partners in the first stages of pregnancy. However, this does not necessarily mean that they have an increased sex drive, as they may be experiencing nausea and other discomforts from early pregnancy.
In the second trimester, the authors note that sexual desire may increase as the person gets used to their pregnancy and feels more comfortable and at ease. Typically though, as the pregnancy develops and reaches the third trimester, sex drive declines rapidly.
During the weekend
Research shows that timing can be an important factor in determining when a person feels horny. At the weekend, the likelihood of college-age females having sexual contact was double or even triple that on weekdays. The average probability of a female having sex was 22% on weekend days vs. 9% on other days.
However, the researchers do note that the conflicting schedules of cohabiting partners during the week may have played some role in increasing the odds of sexual contact at the weekend.
Sexual arousal is closely linked to hormone levels, especially those of hormones relating to the menstrual cycle.
The menstrual cycle
The menstrual cycle begins on day 1 of a period and consists of two main phases: the follicular phase and the luteal phase.
The first half of the cycle is called the follicular phase. During this phase, estrogen levels are higher than progesterone levels.
Females tend to feel more sexual arousal toward the end of the follicular phase when there is a surge of the luteinizing hormone (LH). This point in the cycle marks the start of ovulation and is the time when conception is more likely to happen.
The second phase of the cycle, after ovulation, is the luteal phase. In this part of the cycle, progesterone levels begin to overtake estrogen levels. However, both start to decline toward the end of the cycle to allow for menstruation, which signals the beginning of a new cycle.
As well as feeling less horny during this part of the cycle, females may also process emotions differently. A 2018 study found that in the late luteal phase, females are sadder and experience less amusement in comparison with males.
Attitudes to kissing
A 2013 study found that attitudes toward romantic kissing vary with the menstrual cycle. Females in the follicular phase rated the importance of kissing in the initial stages of a relationship more highly than females in the luteal phase.
As the late follicular phase occurs just before ovulation, this suggests that females value kissing to assess a potential mate, when the chances of conception are at their highest.
The luteal phase, on the other hand, occurs after ovulation, when the likelihood of conceiving is starting to decrease.
Arousal may peak at slightly different times during the month, especially if ovulation occurs later.
A 2019 study looked at more than 600,000 menstrual cycles that people had entered into an app and found that the majority of females did not ovulate on day 14. The average amount of time spent in the luteal phase was also 12.4 days, not 14.
According to a 2013 study, continuously high sexual desire may carry costs, such as increasing the risk of sexually transmitted infections (STIs). Therefore, there may be benefits to the libido falling during less fertile phases of the menstrual cycle.
In a 2013 study, researchers measured the levels of testosterone, estradiol, and progesterone over one or two menstrual cycles in young females by collecting daily saliva samples. The results showed that progesterone levels negatively predicted sexual desire, whereas estradiol levels positively predicted it. Testosterone did not predict any sexual behavior.
It does not matter whether a person has a low or high sex drive unless it is bothering them. Everyone is different, and there is no “normal.”
People who are distressed or worried about their libido may wish to speak to their doctor or contact a sexual health advice service.
Many females are horniest at or just before they ovulate, due to changes in the levels of hormones relating to the menstrual cycle.
People who are worried about or distressed by their sex drive, whether they feel that it is too high or too low, may find talking to a healthcare professional reassuring and helpful.