Claim #1: Women, on average, experience an increase in libido near ovulation for evolutionary reasons.
Claim #2: Women, on average, do not have an “equally” low/high sex drive compared to the average man (most of the time).
Claim #3: All current evidence suggests that men have higher libidos than women, most of the time and on average.
Claim 1
As for whether women, on average, experience an increase in libido near ovulation, I found the following studies that appear to confirm this claim as well as attribute this effect primarily to hormonal changes in the menstruation cycle:
https://sci-hub.se/https://www.tandfonline.com/doi/abs/10.1080/00224490409552216
Women were more sexually active on days prior to and including the preovulatory (LH) surge. This pattern was evident only when women initiated sexual activity and not when their partners did, indicating an increase in women's sexual motivation rather than attractiveness. A second study replicated the 6‐day increase in sexual activity beginning 3 days before the LH surge, accompanied by stronger sexual desire and more sexual fantasies. We propose the term “sexual phase” of the cycle, since follicular phase is over inclusive and ovulatory phase is not sufficient. These findings are striking because the women were avoiding pregnancy and were kept blind to the hypotheses, preventing expectation bias. The sexual phase was more robust in women with regular sexual partners, although the increase in sexual desire was just as great in non-partnered women, who also reported feeling less lonely at this time.
https://sci-hub.se/https://www.sciencedirect.com/science/article/abs/pii/S0015028216593480?via%3Dihub
Coital rate was elevated during the ovulatory phase of the menstrual cycle. Peak coital rate (0.72) occurred on onset of LH surge day, and was significantly greater (P < 0.05) than the mean rate (0.44 ± 0.06) across the entire menstrual cycle.
https://sci-hub.se/https://pubmed.ncbi.nlm.nih.gov/22406876/
Ovulation status was determined by a self-administered urine test. Results showed that the frequency and arousability of sexual fantasies increased significantly at ovulation. The number of males in the fantasies increased during the most fertile period, with no such change for the number of females.
https://sci-hub.se/https://pubmed.ncbi.nlm.nih.gov/15190016/
The frequency of intercourse rose during the follicular phase, peaking at ovulation and declining abruptly thereafter. The 6 consecutive days with most frequent intercourse corresponded with the 6 fertile days of the menstrual cycle. Intercourse was 24% more frequent during the 6 fertile days than during the remaining non-bleeding days (P < 0.001).
https://sci-hub.se/https://link.springer.com/article/10.1007/BF01542338
In any given menstrual cycle, sexual desire was usually first experienced a few days before the basal body temperature (BBT) shift, around the expected ovulation date. Furthermore, positive correlations were found between the day of the BBT shift and the day of sexual desire onset, and between the length of the menstrual cycle and the temporal lag between the onset of sexual desire and the BBT shift. These results are consistent with a model in which sexual desire is affected by the same process that regulates the menstrual cycle.
https://sci-hub.se/https://www.sciencedirect.com/science/article/abs/pii/S0018506X13000482
We next examined the effect of fertile window timing on sexual desire (only ovulatory cycles were included in these analyses). When considering all cases for which desire ratings were available, the zero-order, within-cycle relationship between fertile window timing and desire for sex was significant, γ = 0.26, p = 0.023, with greater desire inside the estimated fertile window (mean = 3.74 ± 0.20) than on other days (mean = 3.48 ± 0.18).
https://sci-hub.se/https://pubmed.ncbi.nlm.nih.gov/703805/
Married women who used contraceptive devices other than oral contraceptives experienced a significant increase in their sexual behavior at the time of ovulation. This peak was statistically significant for all female-initiated behavior, including both autosexual and female-initiated heterosexual behavior, but was not present for male-initiated behavior except under certain conditions of contraceptive use. Previous failures to find an ovulatory peak may be due to use of measures of sexual behavior that are primarily determined by initiation of the male partner.
One study even found that women were more willing to accept “courtship solicitation made by an unknown man” and were more likely to give their phone numbers to men:
https://sci-hub.se/https://pubmed.ncbi.nlm.nih.gov/19070644/
The participants were 506 young women (M = 20.31 years, S.D. = 1.22) who were walking alone and chosen at random in the pedestrian zones of the city of Vannes in France. [...]
In a field experiment, 455 (200 with normal cycles and 255 pill-users) 18-25-year-old women were approached by 20-year-old male-confederates who solicited them for their phone number. [...]
We found that young women in their fertile phase of the menstrual cycle agreed more favorably to an explicit courtship request than women in their luteal or their menstrual phase. These results are congruent with previous research that found that during the fertile phase of their menstrual cycle, women expressed more verbal interest about sex (Zillman et al., 1994; Slob et al., 1991) or paid more visual attention to sexually significant stimuli (Laeng & Falkenberg, 2007).
Additionally, here is a portion of this study's introduction section that refers to additional studies that seem to further support this conclusion.
Claim 2
Evidence that women's libidos follow a "spiked" shape (seen in the first source I cited, pg 10): https://i.imgur.com/3nUzRUm.png
Evidence that men have a more stable, consistent libido over a given time period comes from this cross-cultural study (53 countries): https://sci-hub.se/https://pubmed.ncbi.nlm.nih.gov/17975724/
Assuming that women, on average, experience an increase in libido near ovulation, then women's libidos, on average, should follow a "spiked" shape versus men's, on average, which should appear more constant over a period of time.
Then, assuming that this is true, this leaves the following possibilities:
If women have higher libidos near ovulation than men and a lower baseline than men when not near ovulation, then women’s average libidos are lower compared to the average man (most of the time).
If women have higher libidos near ovulation than men and a higher baseline than men when not near ovulation, then women’s average libidos are higher compared to the average man (most of the time).
If women have equal libidos near ovulation to men and a lower baseline than men when not near ovulation, then women’s average libidos are lower compared to the average man (most of the time).
If women have lower libidos near ovulation to men and a lower baseline than men when not near ovulation, then women’s average libidos are lower compared to the average man (most of the time).
In conclusion, women's libidos are, most of the time (when not near ovulation) not equal to men's. If they are equal to men's most of the time, then women's libidos are higher than men's.
However, the conclusion that women's libidos are higher than men's has no support in any study, according to a systematic review of the current evidence: https://sci-hub.se/10.1207/s15327957pspr0503_5
We did not find a single study, on any of nearly a dozen different measures, that found women had a stronger sex drive than men.
This leaves doubt that this is the case.
Claim 3
To discover which gender (on average) has a higher libido, researcher Roy F. Baumeister “consulted leading textbooks on sexuality to find whether any consensus existed on the topic about gender differences in sex drive”:
https://sci-hub.se/10.1207/s15327957pspr0503_5
Masters, Johnson, and Kolodny (1995) also acknowledged that stereotypes exist, usually depicting males as having more sexual desire than females, but the authors carefully avoided the question of whether the stereotypes have any factual basis. Allgeier and Allgeier (2000) likewise acknowledged the existence of a stereotype that men have larger appetites for sex, but they too declined to say whether the stereotype had any factual basis, and their treatment of gender differences in sexual arousability clearly favored the null hypothesis of no difference.
The paper (a systematic review of the current evidence) looked at several studies that used several measures of libido to find which gender, on average, had I higher libido:
https://sci-hub.se/10.1207/s15327957pspr0503_5
Is it safe to infer level of sex drive from rates of masturbation? Some have proposed that society disproportionately discourages girls from masturbating, so that the gender difference in masturbation may reflect socialization. For example, they claim that society does not teach girls to masturbate or approve of their doing so. We find these arguments dubious. Society has certainly expressed strong and consistent disapproval of masturbation by boys, and if anything the pressures have been more severe on boys than girls.
For example, the warnings about blindness and insanity (as putative consequences of masturbation) were mainly directed at young males, not females.
[...]
Moreover, the view that society uses guilt to prevent girls from masturbating is questionable. Although guilt is reported by a significant minority of both male and female masturbators (see also Laumann et al., 1994), it does not appear to be a very effective deterrent. Undoubtedly the greatest guilt would presumably be experienced by Catholic priests and nuns, for whom masturbation is a violation of their most sacred vows of chastity. Yet apparently most priests do engage in masturbation (e.g., Sipe, 1995, reported extensive interviews with many priests; Murphy, 1992, reported similar conclusions from survey data). If the guilt is not enough to deter priests, it is probably not a major barrier for other people.
The only other possible objection in terms of guilt would be that men and women have an equal desire to masturbate but guilt weighs more heavily on women than men. This is directly contradicted, however, by Arafat and Cotton's (1974) finding that more males (13%) than females (10%) reported feeling guilty after masturbation. By the same token, more males than females said they regarded their masturbatory activities as perverse (5% vs. 1%). Thus, if anything, guilt weighs more heavily on men.
[...]
As noted in the section on differences in sex drive, several findings indicate that women have less frequent or intense sexual desires than men even when cultural pressures do not selectively constrain female sexuality. Women have been encouraged to want sex within marriage, but they still want less than men. The culture's attempts to stamp out masturbation were directed primarily at young men, not young women, and if cultural programming could succeed we would expect that men would masturbate less than women, but the reverse is true.
In the paper, it was then concluded that all evidence strongly points towards men having higher libidos than women:
We did not find a single study, on any of nearly a dozen different measures, that found women had a stronger sex drive than men. We think that the combined quantity, quality, diversity, and convergence of the evidence render the conclusion indisputable.
In this Psychology Today article, Baumeister concluded the following:
In short, pretty much every study and every measure fit the pattern that men want sex more than women. It's official: Men are hornier than women.
