Available online at:
https://cc.arcabc.ca/islandora/object/cc%3Apsycjournal

J Camosun Psyc Res. (2023). Vol. 5(1), pp. 1-15.
Submitted Winter 2023; accepted June 2023.

Biological Causes of Female Sex Drive.
Authors: Callah McCarroll* and Sarah Nuez
Supervising Instructor: Michael Pollock, Psyc 215 (“Biological Psychology”)
Department of Psychology, Camosun College, 3100 Foul Bay Road, Victoria, BC, Canada V8P 5J2
*Corresponding author email: callah@hotmail.com

ABSTRACT
We sought to understand the biological causes of female sex drive so that we could learn
about varying levels of sexual appetite, in genetically female individuals, in order to make
educated choices involving sexuality and intimate partner relationships. Previous research has
found that biological causes of sex drive in women include ovulation, nitric oxide levels, and red
wine. In our correlational study, we tested the strength of these relationships by examining
naturalistic daily changes in their variables longitudinally over a period of fourteen days. We
measured ovulation by tracking the menstrual cycle, nitric oxide levels by using salivary nitric
oxide test strips, red wine by tracking daily red wine consumption, and sex drive by completing a
daily Female Sexual Function Index questionnaire. Data pooled across participants in our
correlational study showed that red wine intake showed no correlation to increased sex drive,
days further from ovulation showed slight increase in sex drive, and that lower nitric oxide levels
correlated with higher sex drive. These results can help inform future research on biological
causes of the female sex drive for diverse groups.
1. Introduction

manipulate one’s own desire levels in order
to accommodate a specific outcome.

1.1 Research Problem
1.2 Literature Review
We sought to understand the biological
causes of female sex drive in order to learn
about diverse and varying levels of sexual
interest in genetically female individuals.
This information could potentially help
women make educated choices involving
sexuality and intimate partner relationships.
It is beneficial to understand female sex
drive in order to empower women and to
encourage the development of self-esteem in
young women seeking to understand their
sexuality. Once we understand some of the
biological causes behind female sex drive,
this information could potentially be used to

Ovulation was found to be a biological
cause of sex drive in a study by Pillsworth et
al. (2004). Participants of this study were
female university students, both partnered
and non-partnered and who were not on any
kind of hormonal birth control. Researchers
used menstruation tracking to measure
ovulation and its associated symptoms.
Researchers used questionnaires to measure
the sex drive of ovulating women not on
hormonal birth control. The questionnaire
was in two parts. The first part consisted of
9 questions centered around the participant’s
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self-perception of sexiness and how
physically attractive they felt each day. The
second part of the questionnaire asked
women in committed relationships how
often they flirted with, or felt desire for,
someone other than their partner. It was
found that partnered women were more
likely to have a higher sex drive during
ovulation. However, overall sexual desire
was not correlated with relationship status.
Circulatory nitric oxide levels in the
body were found to be a biological cause of
sex drive in a study by Meston et al. (2008).
Participants from this study were 99 women
aged 18-65 experiencing sexual arousal
disorder. The study was divided into shortand long-term effects. The short-term trial
measured the participants’ responses 90
minutes after a dose of gingko biloba to
stimulate nitric oxide levels, and for the
long-term trial they were either given ginkgo
biloba extract alone, a placebo, sex therapy,
or ginkgo biloba extract combined with sex
therapy for an 8-week trial. This study used
vaginal photoplethysmography to measure
vaginal pulse amplitude (VPA) in response
to an erotic film. A 0-7 scale was used for
subjective ratings of sexual arousal. The
short-term trial showed significantly higher
VPA responses in women who took the dose
of gingko, although they reported to not
experience higher arousal. Results showed
that long-term increased nitric oxide levels
combined with sex therapy was successful in
increasing sex drive, but that long-term
increased nitric oxide alone showed no
results.
Red wine was found to be a biological
cause of female sex drive in a study by
Mondaini et al. (2009). The participants
were 798 women aged 18-50. The women
were divided into categories of 1) moderate
daily red wine consumption (1-2
glasses/day), 2) no red wine consumption,
and 3) more than 2 glasses of red wine per

day. The women were asked to complete the
Female Sexual Function Index
questionnaire, which is a series of questions
such as, “how satisfied were you with your
ability to reach orgasm (climax) during
sexual activity” and “how satisfied have you
been with your overall sexual life?”. The
Female Sexual Function Index questionnaire
was used to measure female sexual function
across 6 categories: arousal, desire,
satisfaction, lubrication, orgasm, and pain.
Group 1) had significantly higher scores in
the category of desire, which asks the
participants how often and how severely
they felt sexual desire, on a scale of 1-5.
1.3 Hypotheses
Based on the above literature review, we
predicted the following hypotheses:
Hypothesis #1: If days to/from ovulation
increase then sex drive will decrease.
Hypothesis #2: If nitric oxide levels
increase then sex drive will increase.
Hypothesis #3: If red wine intake
increases then sex drive will increase.
2. Methods
2.1 Participants
The two authors of this paper served as
the participants in its studies. The
participants ranged in age from 23 to 45,
with an average age of 32.5. The participants
in this group are one cisgender,
heterosexual, able-bodied female and one
cisgender, queer, able-bodied female. The
participants were all undergraduate students
at Camosun College who completed the
current studies as an assignment for Psyc
215 (Biological Psychology) and were
grouped together due to their mutual interest
in the biological causes of female sex drive.
The participants vary from never having had
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a strong sex drive to having always had a
strong sex drive.
2.2 Materials and Procedures
We first performed a correlational study
to test concurrently all of our hypotheses by
examining naturalistic daily changes in their
variables longitudinally. Over a period of
four weeks, each participant recorded selfobservations of the following 4 variables:
(1) ovulation, (2) red wine, (3) nitric oxide
and (4) female sex drive.
Ovulation: By maintaining daily tracking
of the menstrual cycle, with Day 1 being the
first day that bleeding starts, we were able to
keep track of when ovulation occurs, which
is mid-way through the cycle. For an
average 28 day cycle, ovulation occurs on
Day 14 (see Appendix A). This variable was
quantified by measuring the number of days
to/from ovulation.
Nitric Oxide: Circulatory nitric oxide
levels were measured using Nitric Oxide
Indicator Strips from TONNYLAB (see
Appendix B). Nitric oxide measurements
were taken at the end of each day. A photo
of the strip was taken each time under the
exact same lighting conditions, and analysis
of the resulting color change was quantified
using the eye-dropper tool in the Paint
program in Windows. The resulting
luminance, or Lum number, was used to
detect varying color changes on the indicator
strip. Full luminance is 255 (white) and is
indicative of no nitric oxide, while a 0 Lum
setting results in black and is indicative of
high levels of nitric oxide.
Red wine: Red wine intake was measured
daily by recording the milliliters of red wine
consumed, if any.
Female sex drive: Sexual interest/activity
was recorded each day by completing a
modified Female Sexual Function Index
(FSFI; see Appendix C). The sections on
lubrication and pain were omitted, and the

questions reference a 24 hr period, rather
than a 4-week period as seen in the original.
The Female Sexual Function Index is a
questionnaire that measures sexual
functioning using a numerical scale across
six categories: desire, arousal, lubrication,
orgasm, satisfaction, and pain. With the
omitted categories, the questionnaire
generates a score between 2.0 - 24.0, with
2.0 being low sex drive and 24.0 being high.
2.3 Planned Analyses
To assess the strength and statistical
significance of associations between
variables predicted by our 3 hypotheses, we
performed Pearson product moment
correlations of their predictor variables
(ovulation, nitric oxide levels, and red wine)
with their outcome variable (female sex
drive). For testing Hypothesis #1, we
correlated the days to/from ovulation with
the level of sexual interest. For testing
Hypothesis #2, we correlated the level of
nitric oxide in the saliva with the level of
sexual interest. For testing Hypothesis #3,
we correlated the amount of red wine
consumed each day with the level of sexual
interest. We performed all of the above
correlations separately for each participant
as well as using data pooled across all of the
participants. For the correlations using
pooled data, in addition to using the raw
data, we also performed correlations after
we had first transformed the data from each
participant into z-scores in order to
standardize differences in averages and
variability seen between the participants in
their data and thus make them more
comparable. A correlation coefficient was
considered statistically significant if the
probability of its random occurrence (p) was
< .05 (i.e., less than 5% of the time expected
by chance alone).

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3. Results
This study showed no significance in the
relationship between red wine and sex drive
(see Table 3), while nitric oxide levels and
days away from ovulation both showed
significant results (see Tables 1&2). The
correlation between days away from
ovulation and sex drive showed no
significance for Participant #1 (r = 0.16, p =
0.56), high significance for Participant #2 (r
= 0.82, p = 0.00059), no significance for
pooled raw data (r = 0.03, p = 0.89; see
Figure 1), and significance for pooled
standardized data (r = 0.43, p = 0.019; see
Figure 2). The correlation between nitric
oxide levels and sex drive showed no
significance for Participant #1 (r = 0.28, p =
0.28), high significance for Participant 2 (r =
0.89, p = 0.000015), significance for pooled
raw data (r = -0.44, p = 0.016; see Figure 3),
and significance for pooled standardized
data (r = 0.53, p = 0.0026; see Figure 4).
The correlation between red wine intake and
sex drive showed no significance for
Participant #1 (r = 0.04, p = 0.87), no
significance for Participant #2 (r = 0.19, p =
0.57), no significance for pooled raw data (r
= -0.06, p = 0.74; see Figure 5), and no
significance for pooled standardized data (r
= 0.10, p = 0.59; see Figure 6). Of the three
variables, the strongest correlation was
between low nitric oxide levels and higher
sex drive with an r-value of 0.53 for the
pooled standardized data.
4. Discussion
4.1 Summary of Results
Based on previous research, we
hypothesized that an increase in red wine,
higher circulatory nitric oxide levels, and
proximity to ovulation, would result in
higher sex drive. Although the correlation

between nitric oxide & sex drive, and
ovulation & sex drive was significant, the
results showed correlations in the opposite
directions from what we originally predicted
in our hypotheses. Our correlational study
showed no significant relationship between
red wine consumption and sex drive.
4.2 Relation of Results to Past Research
In the study by Pillsworth et al. (2004),
proximity to ovulation was found to be a
biological cause of elevated sex drive in
women who were in relationships, but no
relation was found between ovulation and
sex drive for single women. Pillsworth et al.
(2004) hypothesized that women who were
in a relationship were more likely to want
sex closer to ovulation to enable higher
conception probability, with the paired
women being hypothetically ready to
procreate and the single women being not.
Our study showed significance for higher
sexual desire on days further from ovulation,
which opposes our hypothesis that days
closer to ovulation would result higher
desire. In our correlational study, Participant
#1 was beyond healthy child-bearing years,
while Participant #2 was single and not yet
ready for procreation, which supports the
hypothesis that higher sex drive near
ovulation is driven by conception. This
might explain why our results were different
from those of the mated women, but likely
closer to the results of the single women in
the Pillsworth et al. (2004) study.
Circulatory nitric oxide is a known
vasodilator, which can increase blood flow
to genitalia and stimulate arousal (Meston,
2008). In a study by Meston et al. (2008),
subjects were given gingko biloba, which
supplies flavonoids that increase nitric oxide
levels, and their results showed that sex
drive did increase when gingko biloba intake
was coupled with sex therapy, but there
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were no significant results with long-term
gingko biloba intake alone. In the short-term
trial of the study by Meston et al. (2008),
women who took one dose of gingko biloba
to increase nitric oxide levels showed
significantly higher vaginal pulse amplitude
responses after 90 minutes, although they
reported to not experience higher sexual
arousal. This suggests that genital
vasodilation does increase with a rise in
nitric oxide levels, but may not contribute to
the improvement of the overall conscious
sexual experience. If this is the case, a
questionnaire such as the FSFI would not be
sufficient in measuring the changes in sex
drive due to fluctuating nitric oxide levels.
The results of our two-week study showed a
correlation between low nitric oxide levels
and higher sex drive for both participants,
which opposes out hypothesis that increased
nitric oxide levels would result in higher
arousal. It is interesting to note, however,
that Participant #2 did have both high sex
drive and high nitric oxide levels compared
to Participant #1 who had consistently low
measurements for both. A further study
would be to test the nitric oxide levels of a
much larger group of women and compare it
to their overall sex drive in a betweensubjects design. Meston et al. (2008)
conducted their short-term and long term
trials each with a within-subjects design.
In a study by Mondaini et al. (2009), it
was hypothesized that regular moderate red
wine intake would increase overall sex drive
in women. As with the gingko biloba, red
wine contains flavonoids that boost nitric
oxide levels, which contribute to blood flow
to genitalia. That study showed that women
who drank 1-2 glasses of red wine daily
showed significantly higher scores in sexual
desire using the FSFI questionnaire. Our
study showed no correlation between red
wine consumption and higher sex drive. In
our correlational study, our consumption of

red wine was quite variable and likely did
not result in a consistent increase in nitric
oxide, and therefor sex drive. Also, it is
possible that the impairment of brain activity
by alcohol could inhibit the cognitive
experience of sexual arousal, essentially
cancelling out the effects of red wine.
4.3 Implications of Results
The goal of our research was to increase
understanding of the biological causes of sex
drive for genetically female individuals, in
order to enable increased control over sexual
encounters. This type of research could help
to improve gender equity by giving women
tools to manipulate their own desire levels.
Women with high sex drives can often find
themselves in awkward, or even dangerous
situations, while women with low sex drives
risk having troubled intimate partner
relationships. Having the ability to increase
or decrease sexual appetite through diet or
home remedies would help mitigate risks
involved in sexual encounters and give
women sexual confidence, leading to a
higher quality of life.
References
Meston, C. M., Rellini, A. H., & Telch, M.
J. (2008). Short- and long-term effects of
Ginkgo biloba extract on sexual
dysfunction in women. Archives of
Sexual Behavior, 37(4), 530–547.
https://doi.org/10.1007/s10508-008-93162
Mondaini,N., Cai, T., Gontero, P., Gavazzi,
A., Lombardi, G., Boddie, V., &
Bartoletti, R. (2009). Regular moderate
intake of red wine is linked to a better
women's sexual health. Journal of Sexual
Medicine, 6(10), 2772-2777.
https://doi.org/10.1111/j.17436109.2009.01292.x
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Pillsworth, E. G., Haselton, M. G., & Buss,
D. M. (2004). Ovulatory shifts in female
sexual desire. Journal of Sex Research,
41(1), 55–65.
https://doi.org/10.1080/00224490409552
213

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Table 1: Statistical results for correlations between ovulation and sex drive.
Participant
Participant #1
Participant #2
Pooled raw data
Pooled standardized data

r
0.16
0.82
0.03
0.43

n
17
12
29
29

p
0.557768
0.000592
0.893183
0.019584

Significance
Not significant
Significant
Not significant
Significant

Notes. r = correlation coefficient, n = number of days sampled, p = probability of achieving this
result by chance.

Table 2: Statistical results for correlations between nitric oxide levels and sex drive.
Participant
Participant #1
Participant #2
Pooled raw data
Pooled standardized data

r
0.28
0.89
-0.44
0.53

n
17
12
29
29

p
0.283313
1.5E-05
0.016327
0.002635

Significance
Not significant
Significant
Significant
Significant

Notes. r = correlation coefficient, n = number of days sampled, p = probability of achieving this
result by chance.

Table 3: Statistical results for correlations between red wine consumption and sex drive.
Participant
Participant #1
Participant #2
Pooled raw data
Pooled standardized data

r
0.04
0.19
-0.06
0.10

n
17
12
29
29

p
0.866303
0.566868
0.741655
0.592276

Significance
Not significant
Not significant
Not significant
Not significant

Notes. r = correlation coefficient, n = number of days sampled, p = probability of achieving this
result by chance.

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Figure 1: Association Between Days to/from Ovulation and Sex Drive Using Pooled Raw Data

Sex Drive (Numerical FSFI score )

30
25
20
15

10
5
0
0

2

4
6
8
10
Ovulation (Days to/from ovulation)

12

14

Notes. Marker colour differentiates participants: red = Participant #1 and orange = Participant
#2. Some data might not be visible in the figure due to overlapping markers.

Figure 2: Association Between Days to/from Ovulation and Sex Drive Using Standardized Raw
Data
2.5
2

Sex Drive (z-score)

1.5

-2

1
0.5
0
-1.5

-1

-0.5 -0.5 0

0.5

1

1.5

2

-1
-1.5
-2
-2.5
Ovulation (z-score)

Notes. Marker colour differentiates participants: red = Participant #1 and orange = Participant
#2. Some data might not be visible in the figure due to overlapping markers.

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Figure 3: Association Between Nitric Oxide Levels and Sex Drive Using Pooled Raw Data

Sex Drive (Numerical FSFI score )

30
25
20
15
10
5
0
0

50

100
150
Nitric Oxide (Luminance )

200

250

Notes. Marker colour differentiates participants: red = Participant #1 and orange = Participant
#2. Some data might not be visible in the figure due to overlapping markers.

Figure 4: Association Between Nitric Oxide levels and Sex Drive Using Standardized Raw Data
2.5
2

Sex Drive (z-score)

1.5

-2.5

1
0.5
0
-2

-1.5

-1

-0.5

-0.5

0

0.5

1

1.5

2

-1
-1.5
-2
-2.5
Nitric Oxide (z-score)

Notes. Marker colour differentiates participants: red = Participant #1 and orange = Participant
#2. Some data might not be visible in the figure due to overlapping markers.
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Figure 5: Association Between Red Wine Consumption and Sex Drive Using Pooled Raw Data

Sex Drive (Numerical FSFI score )

30
25
20
15
10
5
0

0

50

100

150
200
250
Red Wine (millilitres)

300

350

400

Notes. Marker colour differentiates participants: red = Participant #1 and orange = Participant
#2. Some data might not be visible in the figure due to overlapping markers.

Figure 6: Association Between Red Wine Consumption and Sex Drive Using Standardized Raw
Data
2.5
2

Sex Drive (z-score)

1.5

-1.5

1
0.5
0
-1

-0.5

-0.5

0

0.5

1

1.5

2

2.5

-1
-1.5
-2
-2.5

Red Wine (z-score)

Notes. Marker colour differentiates participants: red = Participant #1 and orange = Participant
#2. Some data might not be visible in the figure due to overlapping markers.
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Appendix A - Hormonal fluctuation during the menstrual cycle

Image taken from https://clube.zeros.eco/male-vs-female-hormone-cycle-h-40529653

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Appendix B - Nitric Oxide Indicator Strips used to measure nitric oxide levels

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Appendix C - Modified Female Sexual Function Index with scoring table
Female Sexual Function Index Scoring

Category

Questions

Factor

Min.
Score

Max.
Score

Desire

1,2,

0.6

1.2

6.0

Arousal

3,4,5,6,

0.3

0

6.0

Orgasm

11,12,13

0.4

0

6.0

Satisfaction

14,15,16

0.4

0.8

6.0

2.0

24.0

Total

Score

The individual domain scores and overall score of the FSFI can be derived from the
computational formula outlined in the table above. For individual category scores, add the scores
of the individual items that comprise the category and multiply the sum by the factor. Add the
four scores to obtain the overall score. It should be noted that within the individual categories, a
score of zero indicates that the subject reported having no sexual activity during the past 24 hrs.

FSFI Questions:
1 Over the past 24 hrs., how often did you feel sexual desire or interest?
5 = Almost always or always 4 = Most times (more than half the time) 3 = Sometimes (about
half the time) 2 = A few times (less than half the time) 1 = Almost never or never
2 Over the past 24 hrs, how would you rate your level (degree) of sexual desire or interest?
5 = Very high 4 = High 3 = Moderate 2 = Low 1 = Very low or none at all
3 Over the past 24 hrs, how often did you feel sexually aroused ("turned on") during sexual
activity or intercourse?
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0 = No sexual activity 5 = Almost always or always 4 = Most times (more than half the time) 3 =
Sometimes (about half the time) 2 = A few times (less than half the time) 1 = Almost never or
never
4 Over the past 24 hrs, how would you rate your level of sexual arousal ("turn on") during
sexual activity or intercourse?
0 = No sexual activity 5 = Very high 4 = High 3 = Moderate 2 = Low 1 = Very low or none at all
5 Over the past 24 hrs, how confident were you about becoming sexually aroused during
sexual activity or intercourse?
0 = No sexual activity 5 = Very high confidence 4 = High confidence 3 = Moderate confidence 2
= Low confidence 1 = Very low or no confidence
6 Over the past 24 hrs, how often have you been satisfied with your arousal (excitement)
during sexual activity or intercourse?
0 = No sexual activity 5 = Almost always or always 4 = Most times (more than half the time) 3 =
Sometimes (about half the time) 2 = A few times (less than half the time) 1 = Almost never or
never
11 Over the past 24 hrs, when you had sexual stimulation or intercourse, how often did you
reach orgasm (climax)?
0 = No sexual activity 5 = Almost always or always 4 = Most times (more than half the time) 3 =
Sometimes (about half the time) 2 = A few times (less than half the time) 1 = Almost never or
never
12 Over the past 24 hrs, when you had sexual stimulation or intercourse, how difficult was it
for you to reach orgasm (climax)?
0 = No sexual activity 1 = Extremely difficult or impossible 2 = Very difficult 3 = Difficult 4 =
Slightly difficult 5 = Not difficult
13 Over the past 24 hrs, how satisfied were you with your ability to reach orgasm (climax)
during sexual activity or intercourse?
0 = No sexual activity 5 = Very satisfied 4 = Moderately satisfied 3 = About equally satisfied
and dissatisfied 2 = Moderately dissatisfied 1 = Very dissatisfied
14 Over the past 24 hrs, how satisfied have you been with the amount of emotional closeness
during sexual activity between you and your partner?
0 = No sexual activity 5 = Very satisfied 4 = Moderately satisfied 3 = About equally satisfied
and dissatisfied 2 = Moderately dissatisfied 1 = Very dissatisfied
15 Over the past 24 hrs, how satisfied have you been with your sexual relationship with your
partner?
5 = Very satisfied 4 = Moderately satisfied 3 = About equally satisfied and dissatisfied 2 =
Moderately dissatisfied 1 = Very dissatisfied
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16 Over the past 24 hrs, how satisfied have you been with your overall sexual life?
5 = Very satisfied 4 = Moderately satisfied 3 = About equally satisfied and dissatisfied 2 =
Moderately dissatisfied 1 = Very dissatisfied

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