Open Journal of O bste tric s and Gyne c ology , 2014, 4, 10-15 OJOG
http://dx.doi.org/10.4236/ojog.2014.41003 Published Online January 2014 (http://www.scirp.org/journal/ojog/)
Experience of more than 30 00 cycles of Brazilian women
using the contraceptive vagi n al rin g (nuvaring®)
Denise Leite Maia Monteiro1,2*, Ricardo Vasconcelos Bruno3, Zuleide A. F. Cabral4,
Célia Regina da Silva5, Danielle Bittencourt Sodré Barmpas6, Nádia Cristina Pinheiro Rodrigues7
1Gynecology and Obstetrics Department, Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, Brazil
2Gynecology and Obstetrics Department, UNIFESO, Teresópolis, Brazil
3Reproduction Department, Institutode Ginecologia, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
4Gynecology and Obstetrics Department, Universidade Federal de Mato Grosso (UFMT), Cuiabá, Brazil
5Obstetrics Department, Maternidade Escola Universidade Federal do Rio de Janeiro (ME-UFRJ), Rio de Janeiro, Brazil
6Ongoing MSc at UERJ, Rio de Janeiro, Brazil
7Public Health Researcher of Instituto Oswaldo Cruz (FIOCRUZ)/Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro,
Brazil
Received 8 October 2013; revised 8 November 2013; accepted 16 November 2013
Copyright © 2014 De nise Leite Mai a Montei ro et al. This is an open access article distributed under the Creative Commons Attribu-
tion License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly
cited. In accordance of the Creative Commons Attribution License all Copyrights © 2014 are reserved for SCIRP and the owner of
the intellectual prope r ty Denise Leite Maia Monteiro et al. All Copyright © 2014 are guarded by law and by SCIRP as a guardian.
ABSTRACT
Objective: To evaluate the profile of the Brazilianva-
ginal ring user, reasons for choosing it, satisfaction,
menstrual pattern, tolerability, efficacy, side effects
and reasons for discontinuation. Methods: We review-
ed the files of 148 users who attended the Hospital de
Jacarepaguáand private clinics, between 2005 and
2011, in a total of 3107 cycles. Kaplan-Meier survival
curves and regression models were used in statistical
analysis. Results: Th e profile was: single, nulligravida,
30 years (mean) and with university education. The
previous contraception used was mostly the oral hor-
monal contraception (75.7%). Women chose the ring
for: practicality (32.4%), forgetting the pill (32.4%)
and irregular vaginal bleeding (13.5%). The satisfac-
tion degree was 80.5% (119). There were good cycle
control and no pregnancies. Thirty-eight patients dis-
continued the use (25.7%). The main reasons were
wish for pregnancy (6%), spotting (3.4%) and increas-
ed vaginal discharge (2.7%). At the end of the first
year, use of the greatest reduction of continuity pro-
bability was observed (19.3%). Women with side ef-
fects were 68% less likely to be satisfied with the me-
thod than those without (p-value <0.0001). Conclu-
sion: Nuvaring® is an excellent contraceptiveoption
due to its sefficacy, cycle control, tolerability, practi-
cality and safety.
KEYWORDS
Vaginal Ring; Hormonal Contr aception; Efficacy;
Tolerability
1. INTRODUCTION
The combined oral contraceptive pill (COC) is the most-
ly used method of contraception, especially by younger
women with good level of education and no children [1].
However, the literature shows a high prevalence of wo-
men making irregular use of the pill, which interferes
with its efficacy [2]. Some articles report fa ilu re to take 3
to 5 pills per cycle in 30% to 50% of the women [3].
The possibility of other routes of administration can
benefit women who want safe contraception adapted to
their profile and needs. There are few works evaluating
the cr iteria of choice and the satisfaction degre e with the
contraceptive method [4,5]. However there is already evi-
dence of higher satisfaction amongst women who switch-
ed from the COC to a non-oral route [6]. Furthermore,
there are less side effects and problems related to the use
of the vaginal ring than that with the transdermic hor-
monal cont ra c eptive (patch) [6].
The advantages of the non-oral route are that the pro-
ducts have a longer lasting action (no need for daily dos-
ing) and therefore they eliminate the forgetfulness issue;
and that they avoid the hepatic first-pass effect, gastric
intolerance and the serum hormonal fluctuations, provid-
ing a better control of the bleeding pattern [7].
*Corresponding a uthor.

D. L. M. Monteiro et al. / Open Journal of Obstetrics and Gynecology 4 (2014) 10-15
11
The vaginal ring is made of a transparent evatane core
and sheath, with an external diameter of 54 mm and
thickness of 4 mm. It contains 11.7 mg of etonogestrel
and 2.7 mg of ethinylestradiol, with the average daily re-
lease of 120 mcg and 15 mcg, respectively, for a period
of three weeks. It was first approved for market release
in the Netherlands (2001), followed by the EU and USA
(2002) [8].
The aim of this study is to establish the profile of the
Brazilian women who chose the vaginal contraception
and to evaluate their satisfaction degree, menstrual bleed-
ing pattern, tolerability, efficacy, side effects and the rea-
sons for discontinuing the method. This information should
help the health professionals counsel patients who seek a
birth control method which is safe, efficient and does not
require daily dosing.
2. METHODS
This was a retrospective study, based on the analysis of
the files of 148 women who attended either the Ministry
of Health’s Hospital de Jacarepaguá (Rio de Janeiro, Br a-
zil) or private clinics, between 2005 and 2011, reaching
3107 cycles of use of the product. The inclusion criteria
were: to use the vaginal ring for at least one cycle, to
have no known contraindication to the use of estrogen,
no use of drugs that interfere with the metabolism of
contraceptive hormones, not to be breast feeding, not to
be in the postpartum or post abortion period (2 months)
andto have a normal smear test on the recruitment visit.
At the first appointment, all the subjects underwent
clinical and gynecological examinations, including a cer-
vical smear test. They also answered a questionnaire about
their general medical and gynecological history, includ-
ing any previously used contraceptives and the reason
why they had chosen the vaginal ring. The anamneses
and exams were thoroughly registered on the medical
files. All the patients started the use of the vaginal ring
with the sole objective of contraception. Before starting
the use all the women were taught how and when to in-
sert and remove the ring. For women on each kind of
contraceptive, the manufacturer’s prescribing informa-
tion leaflet was observed. The vaginal ring was self-in-
serted into the vagina and was left in place for 21 days
per cycle followed by a 7 day ring-free interval. In all the
follow up appointments the weight and blood pressure
(BP) measurements were added to their files, as well as
all the information about the periods, the use of the me-
thod (satisfaction or interruption) , the side effects and the
use of other medications. The efficacy of the vaginal ring
was determined by the incidence of pregnancy while us-
ing the method. The level of satisfaction was evaluated
by a simple scoring system ranging from 1 to 4, in which
(1) meant the patient was dissatisfied , (2) not very satis-
fied, (3) satisfied and (4) very satisfied. “Satisfaction”
was also analyzed as a binary variable in the survival
analyses and the categories were regrouped in: dissatis-
fied (scores 1 and 2); and satisfied (scores 3 and 4).
For the stat ist ic anal ysis the c atego rica l predi cto rs wer e:
age (<30; ≥30 years), level of schooling (secondary; hi-
gher), marital status (single; married), previous contra-
ceptive method (COC; condom; patch; implant; inj ection;
IUD and diaphragm), length of use (less than 2 years;
from 2 to 3 years; more than 3 years), side effects, rea-
sons why the vaginal ring was chosen and reasons for
quitting.
The categorical variables were described as propor-
tions with a confidence interval of 95% (CI95%). Means
and standard deviations were used to describe the nume-
ric variables. Kap lan-Meier survival curv e was plotted to
describe discontinuity probability of method along the
time. Bivariate log-binomial regression models were us-
ed to assess the association between the characteristics of
the patients (age, schooling , marital status, previous con-
traceptive method and side effects) and the satisfaction
with the vaginal ring. Age adjusted models were applied
to assess user satisfaction with the vaginal ring in rela-
tion to side effects and previous contraceptive method.
The softwares Epi Info/version 3.5.3, R-Project 2.15.2
and Stata/SE 8.0 for Windows were used for the statis-
tical analyses. The research was approved by the Ethics
Committee of the Hospital de Jacarepaguá.
3. RESULTS
The mean age of the users was 29.5 years (16 to 42
years). The method was chosen by adolescents in 8.1%
(12; CI95% 4.3 - 13.7) of cases; patients were between
20 and 29 ye ars in 44% (65; CI95% 35.8 - 52.3); from 30
to 39 in 41.2% (61; CI95% 33.2 - 49.6) and from 40 to
42 in 6.7% (10; CI95% 3.3 - 12.1).
Regarding marital status, 52.7% (78) were single, 41.2%
(61) married and 6.1% (9) divorced. Patients had either
university 79% (117) or high school level of education
21% (31). Menarche had occurred from 8 to 16 years
(mean = 12.4) and the first intercourse from 12 to 25
(mean = 17.1). Roughly half of the patients (50.7%, 75)
were null igravidae, 29.7% (44) had one previous preg-
nancy and 19.6% (29) had two to four previous pregnan-
cies. Prior miscarriages were reported by 11% (16).
Most women had used COC before (75.7%). The other
previously used methods were condom (10.8%), patch
(3.4%), implant (4.1%), injection (2.7%), IUD (1.4%),
diaphragm (0.7%) and none (1.4%). The main reasons
for choosing the vaginal ring were: practicality for 32.4%
(48) of the women, forgetfulness to take the oral contra-
ceptive for 32.4% (48) and irregularvaginal bleeding for
13.5% (20) ( Table 1).

D. L. M. Monteiro et al. / Open Journal of Obstetrics and Gynecology 4 (2014) 10-15
12
Tab le 1. Distribution of the reasons for switching to the con-
traceptive vaginal ring.
Reasons N % CI 95%
Forgetting the oral contraceptive 48 32.4 25 - 40.6
Practicality 48 32.4 25 - 40.6
Irregular bleeding/Metrorrhagia 20 13.5 6.8 - 22.5
Nausea/heartburn 6 4.0 1.5 - 8.6
Breast tenderness 6 4.0 1.5 - 8.6
Safety 5 3.4 1.1 - 7.7
Migraine/headache 4 2.8 0.4 - 5.8
Weight gain 4 2.8 0.4 - 5.8
Decreased libido/PMS/Acne 3 2.0 0.4 - 5.8
Hepatitis/hepnodular
hyperplasia/↑AST
3 2.0 0.4 - 5.8
Patch fell off 1 0.7 0 - 3.7
Total 148 100
A total of 3107 cycles of use were achieved and during
this period there were no pregnancies. The patients re-
ported well controlled menstrual cycles, with a mean of
3.4 days of bleeding. Periods lasted one day in 0.7% (1)
of the women, three days in 60.8% (90), four days in
27.7% (41) and five da ys in 9.5% (14) . Two patients had
amenorrhea (1.4%) but in one of them it was induced by
the continuous use of the method. The satisfaction degree
was 80.5% (n = 119). The specific results were: very
satisfied (71%, n = 105), satisfied (9.5%, n = 14), not
very satisfied (9.5%, n = 14) and dissatisfied (10%, n =
15).
Side effects were reported by 21% (31) of the users,
the most frequent were spotting (8%, 12), increased va-
ginal discharge (4%, 6) and breast tenderness (3.4%, 5).
One patient had a deep vein thrombosis (DVT) and on
the subsequent diagnostic investigation it was found that
she was homozygous for the C677T mutation of the
MTHFR ge ne (Table 2).
The method was interrupted by 25.7% (38) of the us-
ers. The main reasons were: wish to get pregnant in 6%
(9), spotting in 3.4% (5) and increased vaginal discharge
in 2.7% (4). The discontinuation of the method due to
side effects happened in 8.8% (13) of cases (Table 3).
Figure 1 shows the continuity probability of the use of
the vaginal ring over time. There is a significant decrease
(19.3%) at the end of the first year of treatment. From
this point on it becomes less pronounced 7.3% from the
first to second year, 3.9% from the second to third year
and 6.1% from the third to fourth year. The probabilities
of continuity after the first, second, third and fourth years
of use of the ring correspond to 0.81 (95% CI 0.74 -
Figure 1. Continuity probability of use of the vaginal ring over
time (months).
Table 2. Side effects of the contraceptive vaginal ring.
Effects Freq. % CI 95%
None 117 79 71.6 - 85.3
Spotting 12 8.1 4.3 - 13.7
Increased vaginal
discharge 6 4.0 1.5 - 8.6
Breast tenderness 5 3.4 1.1 - 7.7
Discomfort 2 1.3 0.2 - 4.8
Partner felt the ring 2 1.3 0.2 - 4.8
Patient felt the ring 1 0.7 0 - 3.7
Migraine 1 0.7 0 - 3.7
Amenorrhea 1 0.7 0 - 3.7
DVT (trombophilia) 1 0.7 0 - 3.7
Total 148 100
0.88), 0.73 (95% CI 0.66 - 0.82) 0.70 (95% CI 0.61 -
0.80) an d 0.63 (95% C I 0.53 - 0.76), respectively.
Table 4 shows the relationship b etween the main ch a-
racteristics of the patients and the satisfaction with the
vaginal ring. Bivariate analysis (left side of the table)
showed that patients with previous use of condom had a
greater probability of satisfaction with the vaginal ring
than those using COC or other contraceptive method. It
also found an inverse association between the incidence
of side effects and the user satisfaction. After adjusting
the models by age group (right side of the table), this
findings remained statistically significant, indicating that
both “previous method of contraception” and “side ef-
fects” play an important role in determining user’s satis-
faction with the vaginal ring. Women who had previous-
ly used COC or other contraceptive methods were less

D. L. M. Monteiro et al. / Open Journal of Obstetrics and Gynecology 4 (2014) 10-15
13
Tab le 3. Distribution of the reasons for discontinuing the me-
thod.
Reasons Freq. % CI 95%
Still using the ring 110 74.3 66.5 - 81.1
Discontinued due to side effects:
Spotting 5 3.4 1.1 - 7.7
Increased vaginal discharge 4 2.7 0.7 - 6.8
Amenorrhea 1 0.7 0 - 3.7
Migraine 1 0.7 0 - 3.7
Breast tenderness 1 0.7 0 - 3.7
DVT (trombophilia) 1 0.7 0 - 3.7
Discontinued due to other
reasons:
Wish to get pregnant 9 6.0 2.8 - 11.2
Discomfort 2 1.4 0.2 - 4.8
Insecurity 2 1.4 0.2 - 4.8
No sexual activity 3 2.0 0.4 - 5.8
Wish for amenorrhea 3 2.0 0.4 - 5.8
Partner felt the ring 2 1.4 0.2 - 4.8
Ring came out spontaneously 2 1.4 0.2 - 4.8
Difficult to remove 1 0.7 0 - 3.7
Price 1 0.7 0 - 3.7
Total 38 25.7
likely to be satisfied with the ring than the ones who had
used condoms 15% (p-value < 0.001) and 32% (p-value
< 0.02), respectively. The incidence of side effects also
reduced the probability of satisfaction (68%, p-value <
0.0001).
4. DISCUSSION
After evaluating more than 3000 cycles of Nuvaring®,
the profile of the Brazilian woman who opted for the
method was established. Most of the patients (85.2%)
were between 20 and 39 years old, showing good accep-
tance throughout the reproductive age. The adolescents
were the only population with a lower proportion of us-
ers (8.1%), although there is evidence of the product’s
safety [9]. The teenager’s lack of knowledge about the
ring could be due to the shortage of information, as re-
ported by an American study, which found that even if
the girls had hear d about it, only 51% had been informed
by a health professional [10].
There was a predominance of single and nulligravidae
users, which is likely to be a consequence of the mean
age and the schooling level. There is a high percentage of
university students and these women are delaying wed-
ding and pregnancy in order to pursue their higher edu-
cation and career goals. The higher education prevalence
probably represents a selection bias since three of the
recruiting centers were private clinics.
The COC was the main method used previously to the
vaginal ring (more than 75%) and the main reasons for
the switch were practicality and th e fear of forgetting the
daily dosing of the pill, as it was also observed by Let et
al. (2007) [11].
Our Pearl index was 0.0. In the manufacturer’s pre-
scribing information the CI ranges from 0.01 to 1.36.
Ahrend et al. (2006) disagree as they found 0.25 in the
comparison between the Nuvaring® and the oral contra-
ceptives, for which they found 0.99 [12].
The satisfaction degree with the ring was similar to
ours in several studies, with an approval rate of more
than 80% [3,4,9,12,13] and a low rate of discontinuation
of the method. Furthermore, the main reason for stopping
the use was the wish to get pregnant (6%) rather than the
incidence of side effects.
The good control of the cycle, with a low frequency of
spotting (8%) and cycles of 3 - 4 days of bleeding in
more than 88%, were contributing factors to the com-
pliance. This is in agreement with the literatur e, in which
cycle control was found to be excellent, with irregular
bleeding in only 2.6% - 6.4% of cycles [14-16]. In a trial
comparing the vaginal ring and a COC containing 150
µg LNG and 30 µg EE, irregular bleeding and spotting
during cycles 2 to 13 was less frequent with the ring than
with the COC (2% - 6% vs. 4% - 13%) [17]. The hypo-
thesis is that the steady low-dose release of ethyn ilestra-
diol of the vaginal ring favourably affects cycle control
compared with the fluctuating steroid levels between the
peaks caused by the once-a-day pill intake [18]. However
not only the cycle control was important, but the practi-
cality of the method also played a crucial role, especially
the monthly dosing and the easy insertion and removal of
the ring reported by the patients, in opposition to their
considerations regarding the oral contraceptives [14,15].
Counseling and information sharing can help to improve
contraceptive compliance, continuation and user satisfac-
tion.
5. CONCLUSION
The limitations of the study lie in its retro spective design,
which could prompt an information bias due to incom-
plete or inaccurate clinical files. The schooling level and
marital status might represent a bias because patients
were recruited from both private clinics and the public
hospital. But, even if not representative of the whole
population , our study represents the acceptance of a new
contraceptive option by differ e nt g r oups of wom e n.

D. L. M. Monteiro et al. / Open Journal of Obstetrics and Gynecology 4 (2014) 10-15
14
Table 4. Relationship between the main characteristics of the patients and the satisfaction with the vaginal ring.
Characteristics assessed Categories Bivariate analysis
RR (CI 95%) P-value Multivariate
1
analysis
RR (CI 95%)
P-value
Age (years) ≥30/<30 0.93 (0.79 - 1.9) 0.39
Duration of treatment (years)
2 - 3/≤2 1.21 (1.01 - 1.45) 0.06 1.27 (0. 9 9 - 1.62) 0.06
>3/≤2 1.19 (1.01 - 1.40) 0.10 1.17 (0.97 - 1.40) 0.10
Marital status Single/married 0.94 (0.79 - 1.12) 0.47
Previous contraceptive
metho d
COC2/condom 0.81 (0.74 - 0.88) 0.001* 0.85 (0.77 - 0.93) 0.001*
Others3/condom 0.66 (0.48 - 0.92) 0.01* 0.68 (0.49 - 0.94) 0.02*
Side effects Yes/no 0.29 (0.17 - 0.50) 0.0001* 0.32 (0.18 - 0.56) 0.0001*
1Log-binomial multiv ariate mod el (char acterist ics vs . satisfacti on) ad justed b y age; 2COC: co mbined or al contr aception; 3others: patch; implant; injection; IUD
and diaphra gm.
The average Brazilian choosing Nuvaring ® was single,
nulligravida, 30 years old (mean) and with university
education. It proved to be an excellent contraceptive op-
tion for them for its efficacy, good cycle control and to-
lerability, in addition to being a practical and safe choice.
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