DARK CHOCOLATE’S EFFECT ON MENSTRUAL PAIN IN LATE ADOLESCENTS

Abstract

Background: Menstrual pain can be severe enough to interfere with everyday activities for a few day every month, particualrly in activities in homes and schools for late adolescents. Dark chocolate is considered effective in reducing menstrual pain. However, little is known about its effect.Objective: This study aimed to examine the effect of dark chocolate on menstrual pain in late adolescents.Methods: This was a true experiment study with randomized pretest-posttest with control group design. This study was conducted from September to November 2016 at the Bhakti Husada Boarding School of Poltekkes Kemenkes Semarang. There were 50 samples recruited by simple random sampling, with 25 randomly assigned to the experiment and control group. Numeric Rate Scale (NRS) was used to measure pain. Independent t-test and Mann-whitney were used to examine the effect of intervention. Results: There were significant differences in menstrual pain (p <0.001) before and after treatment. The mean of menstrual pain in the treatment group (2.76 ) was lower than the menstrual pain in the control group (5.36) with p <0.001.Conclusion: Dark chocolate could reduce menstrual pain significantly in the late adolescents.

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Maharani SI, et al. Belitung Nursing Journal. 2017 December;3(6):686-692
Accepted: 14 March 2017
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ORIGINAL RESEARCH ISSN: 2477-4073
DARK CHOCOLATE’S EFFECT ON MENSTRUAL PAIN IN
LATE ADOLESCENTS
Sandy Isna Maharani1*, Noor Pramono2, Sri Wahyuni3
1Postgraduate Midwifery Program, Semarang Health Polytechnic, Semarang, Indonesia
2Medical Faculty of Diponegoro University of Semarang, Indonesia
3Midwifery Program, Semarang Health Polytechnic, Semarang, Indonesia
*Correspondence:
Sandy Isna Maharani
Postgraduate Midwifery Program, Semarang Health Polytechnic
Jl. Tirto Agung, Pedalangan, Banyumanik Kota Semarang, Jawa Tengah, Indonesia (50268)
E-mail: sandyisnam@gmail.com
Abstract
Background: Menstrual pain can be severe enough to interfere with everyday activities for a few day every month,
particualrly in activities in homes and schools for late adolescents. Dark chocolate is considered effective in reducing
menstrual pain. However, little is known about its effect.
Objective: This study aimed to examine the effect of dark chocolate on menstrual pain in late adolescents.
Methods: This was a true experiment study with randomized pretest-posttest with control group design. This study was
conducted from September to November 2016 at the Bhakti Husada Boarding School of Poltekkes Kemenkes Semarang.
There were 50 samples recruited by simple random sampling, with 25 randomly assigned to the experiment and control
group. Numeric Rate Scale (NRS) was used to measure pain. Independent t-test and Mann-whitney were used to examine the
effect of intervention.
Results: There were significant differences in menstrual pain (p <0.001) before and after treatment. The mean of menstrual
pain in the treatment group (2.76 ) was lower than the menstrual pain in the control group (5.36) with p <0.001.
Conclusion: Dark chocolate could reduce menstrual pain significantly in the late adolescents.
Keywords: Adolescent, Menstrual Pain, Dark Chocolate
INTRODUCTION
A teenager is an individual who has already a
mature anatomy and reproductive function
Adolescent puberty is characterized by
elevated levels of hormone luteininzing (LH)
and follicle stimulating hormone (FSH) so
that sex hormones are formed (Santrock &
Santrock, 2007). These hormones mature the
reproductive organs such as the ovaries,
uterus, vagina, breasts, and the appearance of
secondary sexual features such as the
appearance of hair on the armpits, genitals,
fine hairs on the skin, face and so on. This is
also the start of the first menstruation
(menarche). Conditions that we then know
that menstruation will be faced by teenagers
every month. Discomfort that is felt before the
menstrual period and at the time of
menstruation will accompany the teenagers
despite different cycles and times (Santrock &
Santrock, 2007).
Menstrual pain or dysmenorrhea is stiffness or
seizures in the lower abdomen due to
menstruation and production of prostaglandin
substances that occur at the time of or during
menstruation (Widyastuti, Rahmawati, &
Purnamaningrum, 2009). Usually, pain is felt
in the day before the menstrual period and

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lasts for two days or until the end of
menstruation. The prevalence of menstrual
pain vary between 15.8 – 89.5%, with the
high prevalence is in teenager (Llewellyn-
Jones, 2005).
Data in Indonesia showed that primary
menstrual pain is experienced by 60-75% of
young women, with three-quarters of these
suffering from mild to moderate pain and a
further quarter of severe pain. The effects of
primary menstrual pain include activity
disorders such as high absence rates from
school work, social life limitations, academic
performance, and sport activities. The
problem of dysmenorrhoea also affects the
decrease of quality of life due to not attending
school or work (Parker, Sneddon, & Arbon,
2010). It also affects economic loss in women
of childbearing age, and affects the national
economic loss due to the decreasing quality of
life. It can also cause infertility and impaired
sexual functioning if untreated, depressed, and
alteration of cardiac autonomic activity
(Stoelting‐Gettelfinger, 2010). Severe
menstrual pain often disrupts women's
activities and abilities in their daily activities
and functions in homes, schools and
workplaces. Dysmenorrhoea can affect
women's reproductive systems for years. In
some teenagers, primary dysmenorrhea is a
torture that must be experienced every month,
so adolescents should be able to search the
right solution to overcome them.
Some ways can be done to overcome the
symptoms of discomfort during menstrual
period, and the treatment is given by looking
at the severity of symptoms caused, usually in
the form of pharmacological and non-
pharmacological therapy. Some of the things
that can be done to deal with the pain of
menstruation are using drug therapy,
psychotherapy, lifestyle changes, and healthy
diets such as consumption of vegetables,
fruits, complex carbohydrates, exercise,
adequate rest, avoidance of alcohol, high-fat
foods, mineral therapy, vitamins and drugs
(Elvira, 2010).
Science related to dysmenorrhea is still
inadequate to provide specialized clinics,
examining the potential benefits or risks to the
community about interventions such as the
example above. However, there is an
increasing interest in the use of herbs outside
medical therapy derived from traditional
Western countries. There is also evidence to
suggest that not all herbs are safe and concern
about undesirable side effects (Puspitasari &
Novia, 2008). One therapy that can be used as
an alternative to overcome the pain during
premenstruation and menstruation time is dark
chocolate.
Dark chocolate contains many benefits in the
health field. Substances contained in
chocolate are rich in vitamin A, B1, C, D, and
vitamin E. In addition, chocolate also contains
anti-oxidants of phenol and flavonoids, rich in
minerals such as calcium, potassium, iron, a
little omega 3 and 6, and high magnesium
(Nurazizah, Tih, & Suwindere, 2015), which
can reduce menstrual pain and premenstrual
occurrence in women Chocolate, in all of its
forms, starts at the same source:
the Theobroma cacao tree that has been
cultivated over 3,000 years ago by Native
Americans of Central and North America of
South America (cacaoweb, 2016).
The direct effect of magnesium will put
pressure on the blood vessels and will help to
regulate the entry of calcium into the smooth
muscle cells in the body, so that it can affect
the occurrence of contraction, stress and
relaxation of smooth muscle of the uterus.
Therefore, changes that occur in dietary habits
tend to modulate the metabolic status of
individuals who have a free lifestyle that is
closely related to long-term health
consequences. Dark chocolates can reduce
menstrual pain because it has a variety of
ingredients that qualify as a person
(Arfailasufandi, 2015). Data obtained from
the Community Health Center of Pandanaran
showed that the incidence of women who
came with menstrual pain amounted 31
patients in 2015. Of the 31 patients, 11
patients were teenagers. At the time the
patient check, particularly patients who are
still in school, must be accompanied by one of
her parents and ask permission not to attend
the school. Thus, the perceived pain interferes
with their activity. The therapy used is in
accordance with the standards of the health
center, ie the provision of Fe tablets, Vitamin

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K and mafenamat acid, but not yet for the
consumption of dark chocolate.
Preliminary study conducted on 20 female
students living in Bakti Husada Dormitory of
Poltekkes Kemenkes Semarang in March
2016 found that 10 people (50%) said
experiencing menstrual pain every month,
especially from the first day until the second
menstrual period. Because they have not
received the materials in the lectures on pain
management and reproductive health, students
overcome their pain with sleep, rest and some
people drink yogurt or tamarind. Although the
pain does not affect their attendance to school,
but almost all respondents stated that they
have activity disorder when experiencing
menstrual pain. Therefore, with this
phenomenon and the benefit of dark
chocolate. This study aimed to examine the
effect of dark chocolate on menstrual pain in
teenagers.
METHODS
Study Design
This was a true experiment study with
randomized pretest-posttest with control
group design.
Setting
This study was conducted from September to
November 2016 at the Bhakti Husada
Boarding School of Poltekkes Kemenkes
Semarang.
Research Subjects
There were 50 samples recruited by simple
random sampling, with 25 randomly assigned
to the experiment and control group. The
inclusion criteria of the samples included: 1)
young woman aged 18-21 years, 2)
experiencing pre-menstrual pain and
menstrual pain in the last 3 months, 3) regular
menstrual cycle, 4) single, 5) not taking
analgesic medication in the last 24 hours, 6)
and willing to be a respondent. The exclusion
criteria included: young woman diagnosed
with certain gynecologic disease or secondary
dysmenorrhea, and allergic to chocolate.
Instruments
Numeric Rate Scale (NRS) was used to
measure pain. The 10-point numeric scale
ranges from '0' representing one pain
extreme (e.g. “no pain”) to '10' representing
the other pain extreme (e.g. “pain as bad as
you can imagine” or “worst pain
imaginable”) (Judha & Sudarti, 2012). Pain
was measured before and after intervention.
Intervention
Intervention was performed by giving dark
chocolate as much as 40gr / day during the
first 3 days after the menstrual date in the
intervention group, with the assistance of an
enumerator (a housemother). Dark chocolate
was given in the form of a bar that has been
processed in a chocolate-making factory in
Yogyakarta City. Given immediately after the
first day menstruation. While control group
was given 40gr / day of milk chocolate during
the first 3 days after the menstrual date.
Chocolate milk was given because the milk
chocolate provided contains only 20%
chocolate and the rest is made from other
ingredients such as milk, sugar and vegetable
fat as well as other ingredients.
Ethical consideration
Ethical clearance research number: 023 /
KEPK / Poltekkes-SMG / EC / 2017. Prior to
data collection, prospective respondents were
given an explanation of the purpose and
benefits of research, and asked to sign a
written informed consent.
Data Analysis
Descriptive statistics were used in this studty
to describe the mean and frequency
distribution in the experiment and control
group. Independent t-test and Mann-whitney
were used to examine the ffect of
intervention.
RESULTS
Characteristics of the respondents
Table 1 shows that the mean age of the
respondents was 18-19 years old in the
experiment and control group. There were no
significant differences of age, nutrient intake
and BMI between the two groups with p-value
>0.05. It could be said the characteristics of
the respondents between the two groups were
homogenous.

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Table 1 Characteristics of the respondents based on age, nutrient intake, and BMI
Characteristics of respondent
Experiment group
Control group
p-value
Age
Mean (SD)
Median
Min
Max
18.20 (0.408)
18.00
18
19
18.16 (0.374)
18.00
18
19
0.716
Nutrient intake
• Carbohydrate
Mean (SD)
Median
Min
Max
• Magnesium
Mean (SD)
Median
Min
Max
• Calcium
Mean (SD)
Median
Min
Max
• Phosphor
Mean (SD)
Median
Minimum
Max
• Iron
Mean (SD)
Median
Minimum
Max
104.18 (26.06)
112.2
44.8
137.9
149.75 (72.57)
124.7
49.7
326.1
211.53 (180.28)
162.9
26.5
964.2
473.01 (158.7)
406.4
205.9
766
7.61 (1.07)
4.6
2.0
57.2
119.06 (26.38)
118.9
56.5
187.5
158.17 (62.36)
173.1
51.3
254.9
207.84 (96.84)
201
30.4
399.9
501.48 (122.3)
540.1
205.9
667.5
6.07 (2.83)
7.30
2.0
11.5
0.074
0.614
0.404
0.426
0.573
Body Mass index (BMI)
Mean (SD)
Median
Minimum
Max
19.44 (2.27)
18.90
16.42
24.97
19.91 (2.01)
19.25
17.09
25.89
0.347
Table 2 Menstrual pain in the experiment and control group
Group
Frequency
distribution
Pretest
Posttest
p
Experiment
Mean (SD)
7.44 (0.92)
2.76 (1.20)
0.001
Median
7
3
Min
Max
6
9
1
6
Control
Mean (SD)
6.20 (1.04)
5.36 (1.11)
Median
6
5
Min
Max
5
8
3
7
Table 2 shows that the mean of menstrual
pain in the experiment group before given
intervention was 7.44 and decreased to 2.76
after given intervention. While in the control
group the mean of menstrual pain before
given intervention was 6.20 and decreased to
5.36 after given intervention. There was a
significant difference in menstrual pain before
and after given intervention in the two groups
with p-value 0.001 (<0.05). However, the
experiment group shows a higher decrease of
pain compared to the control group.
DISCUSSION
Respondent's Characteristic
The age characteristics of both groups were
the same. The average age was 18.2 years up
to 18.16 years. In this study, the respondent's
age was the late adolescent age (18 to 21

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years). The late adolescents were selected as
respondents because the age group mostly
took education in college, and were more
prone to experiencing pain during
menstruation, with busy activities and easy to
stress and lack of a number of nutrients due to
have poor diet especially during menstruation,
especially minerals and micro substances.
Menstrual pain also reduces the concentration
of adolescents in learning and daily activities
each month.
Food intake of respondents was assessed by
processing the daily menu into the
Nutrisurvey 2007 application in cooperation
with the nutrition section. The application was
used to calculate the amount of nutrients
especially carbohydrates, magnesium,
calcium, iron and phosphorus consumed. The
results obtained show the value or content of
respondent's nutrients in accordance with
what is consumed. In this study, the average
carbohydrate intake of respondents was
104.18 g for the treatment group and 119.06
grams for the control group. Carbohydrates in
teenagers needed is 309 grams (Indonesia,
2013), so it can be seen that the carbohydrate
intake in the respondents was still lacking.
This is because the respondents who were all
women choose to reduce the rice so that their
body weight does not rise. Source of
respondent carbohydrate comes from basic
food such as rice, bread interlude, crackers
and others. In this study, carbohydrate
consumption of respondents was assessed
because carbohydrates is a source of energy
that can also contribute high enough calories
and sugar that could inhibit the absorption of
magnesium and calcium needed by the body
during menstruation, so investigated was done
whether it has a relationship with the
incidence of menstrual pain. However, after
calculated using nutrisurvey2007 application
and processed data using SPSS16, it turns out
carbohydrate intake in both respondents from
the treatment and control group did not have a
significant difference so it can be ascertained
that the carbohydrate intake of the
respondents did not interfere with the
absorption of micronutrients magnesium and
calcium.
The average of magnesium of respondents for
the treatment group was 149.75 mg and
158.17 mg in the control group. At the time of
menstruation occurs, women will lose a
number of minerals and micronutrients in the
body. Magnesium has a natural benefit for
reducing menstrual pain. Magnesium can help
smooth muscle contraction in the uterus
become more relaxed. The need for
magnesium in adolescents based on
Nutritional Adequacy Rate (AKG) is 300 mg /
day. By consuming dark chocolate 69% as
much as 40 grams per day is expected to
increase the amount of magnesium in the
body and reduce pain during menstruation.
Dose of dark chocolate 69% as much as 40 gr
contains enough magnesium that is equal to
115 mg which will help increase the amount
of magnesium in body obtained from food. In
the previous study we found out that
menstrual pain can be overcome by
consuming magnesium as much as 300 mg
during pain (Wulandari & Afriliana, 2017).
In addition to magnesium, a mineral that is
important during menstruation is calsium.
Calsium is able to activate the nerves and
muscle contraction, blood vessel launched
during menstruation, reduce cramps and keep
balance of body fluids. Giving chocolate to
the respondent provides additional calcium in
the body of the respondents amounted 32 mg .
While the need for calcium in adolescents
according to Nutritional Adequacy Rate
(AKG) is 1100 mg (Wulandari & Afriliana,
2017). So consuming dark chocolate in this
study did not affect the decrease of menstrual
pain in the respondents because of the small
amount to be consumed. The results of the
analysis of food intake into the assessment
material again is iron and phosphorus. Iron
and phosphorus become micronutrients that
aid in transporting or transporting processes
for core minerals such as magnesium and
calcium. The results of iron and phosphorus
intake of the respondents were found to be
less than the coverage of nutritional needs
based on AKG.
The average of phosphorus was 473.01 mg for
the treatment group and 501.48 for control
group, which was not in accordance with the
requirement of phosphorus based on AKG
that is 700 mg for phosphorus and 13 mg for
iron. But after having the addition of
phosphorus of dark chocolate consumed

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during menstruation, it was able to add as
much as 132 mg of phosphorus and 3.1 mg
iron. The iron in the treatment group obtained
amounted to 7.61 mg and 6.07 for the control
group. However, the reduction in menstrual
pain indirectly influenced by the consumption
of iron and phosphorus. In addition,
respondents who experienced menstrual pain
in this study had normal nutritional status with
an average BMI of 19.44 (treatment) and
19.91 (control).
Menstrual Pain in the experiment and
control
The results showed an average of menstrual
pain before intervention was 7.44, with
maximum pain score of 9 and minimum pain
score of 6. After given intervention, the
average pain was 2.76, with maximum pain
score of 6 and minimum pain score of 1. The
mean difference before and after given
intervention was 4.68 in the treatment group
and 0.84 in the control group.
Pathophysiologically, menstrual pain is also
often accompanied by headache, nausea,
constipation or diarrhea and frequent
urination, and sometimes until vomiting.
Symptoms and signs of dysmenorrhea are
pain in the lower part that can spread to the
lower back and legs. Pain is felt as a loss of
cramp or as a continuous dull pain. The giving
of dark chocolate decreases menstrual pain in
the respondents. This corresponds to the
theory of dark chocolate containing complex
carbohydrates, antioxidants (flavonoid
polyphenols), vitamin B6, unsaturated fatty
acids (omega 3 and omega 6) and minerals
(magnesium, calcium, iron) that influence in
regulating menstrual cycle by balance the
levels of the estrogen and progesterone
hormones in the blood during the luteal phase
during the menstrual cycle (Speroff & Fritz,
2005).
In a previous study examining the benefits of
dark chocolate to reduce menstrual pain stated
that the chocolate content of GABA (Gamma-
Amino Butyric acid) is an amino acid that has
a major function as a neurotransmitter in the
central nervous system. Gamma aminobutyric
acid inhibits nerve transmission in the brain,
calming nervous activity. The 5-
hydroxytryptophan creates a sense of comfort
and increase serotonin levels. L-taurine gives
rise to body-wide relaxation. L-glutamine can
be utilized directly by the brain for energy
production in brain cells. Thus it can improve
brain function and facilitate the utilization of
GABA and S-HTP (Smith & Smith, 2012). In
theory, magnesium has a direct effect on
vascular pressure and can regulate the entry of
calcium into the smooth muscle cells of the
uterus, so magnesium affects contraction and
relaxation of smooth muscle of the uterus.
Magnesium can also suppress inflammation
by inhibiting the formation of prostaglandins.
So in the group treated with dark chocolate
states menstrual pain is reduced significantly
(Smith & Smith, 2012).
Limitations of the study
The results of this study can only be
generalized in Bhakti Husada Dormitory as
the setting of the study. At the time of data
collection, menstrual conditions in each
respondent were not at the same time so that
data collection could not be done
simultaneously. In addition, to diagnose
secondary menstrual pain was difficult if only
using anamnesa and screening because it has a
low accuracy.
CONCLUSION
In conclusion, there was a significant effect of
dark chocolate in reducing menstrual pain in
the late adolescents (18-21 years). Therefore,
the dark chocolate is recommended to reduce
pain in young women during menstruation.
Further study is needed to have bigger sample
size to generalize the results.
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Cite this article as: Maharani, S. I., Pramono, N., Wahyuni, S. (2017). Dark chocolate’s effect on
menstrual pain in late adolescents. Belitung Nursing Journal, 3(6), 686-692.