Volume 79, Issue 3, November 2014, Pages 316–321
Effects of sea buckthorn oil intake on vaginal atrophy in postmenopausal women: A randomized, double-blind, placebo-controlled study ☆
- Under a Creative Commons license
Open Access
Highlights
- •
- Effects of sea buckthorn (SB) oil intake on vaginal atrophy were investigated.
- •
- Postmenopausal women took SB oil or placebo daily for three months.
- •
- SB oil induced an improvement in the integrity of vaginal epithelium.
- •
- A beneficial trend on vaginal health index was observed in the SB oil group.
Abstract
Background
Vaginal
atrophy, the thinning and drying of vaginal mucosa, is associated with
menopause. The standard estrogen treatment is not suitable for all
women.
Objective
To investigate the effects of oral sea buckthorn (SB) oil supplementation on vaginal atrophy.
Method
A
total of 116 postmenopausal women experiencing symptoms of vaginal
dryness, itching or burning were randomized to this placebo-controlled,
double-blind study. Ninety-eight participants completed the intervention
of three months, during which they consumed 3 g of SB or placebo oil
daily. At the beginning and end, factors of vaginal health were scored
by a gynecologist, vaginal pH and moisture were measured and vaginal
health index was calculated. Symptoms of atrophy and menopause were
evaluated at study visits and by daily logbooks. Serum samples were
collected for the analysis of circulating lipids, liver enzymes and
C-reactive protein.
Results
Compared
to placebo, there was a significantly better rate of improvement in the
integrity of vaginal epithelium in the SB group when both compliant and
noncompliant participants were included (odds ratio (OR) = 3.1, 95% CI
1.11–8.95). A beneficial trend was observed when only the compliant
participants were included (OR = 2.9; 95% CI 0.99–8.35). There was a
tendency (P = 0.08) toward better improvement of vaginal health
index from baseline to the end in the SB group [(0.8 (SD 2.8)] compared
to placebo [−0.1 (SD 2.0)].
Conclusions
SB
oil showed beneficial effects on vaginal health, indicating it is a
potential alternative for mucosal integrity for those women not able to
use estrogen treatment for vaginal atrophy.
Abbreviations
- ALA, α-linolenic acid;
- ALT, alanine aminotransferase;
- AST, aspartate aminotransferase;
- BL, baseline;
- CI, confidence interval;
- CRP, C-reactive protein;
- EPA, eicosapentaenoic acid;
- HDL, high density lipoprotein;
- ITT, intention to treat;
- LA, linoleic acid;
- LDL, low density lipoprotein;
- MI, maturation index;
- OR, odds ratio;
- PP, per protocol;
- Q1, lower quartile;
- Q3, upper quartile;
- SD, standard deviation;
- SB, sea buckthorn;
- VagHI, vaginal health index
Keywords
- Sea buckthorn;
- Vaginal atrophy;
- Menopause;
- Mucous membrane
1. Introduction
Vaginal atrophy, the thinning and drying of vaginal mucosa, is associated with lowered levels of estrogen at menopause [1]. Atrophic tissue is prone to inflammation, petechial hemorrhages and ulceration [2]. Typical symptoms include vaginal discomfort, feelings of dryness, burning, itching and dyspareunia [1].
A prevalence of 43% for the symptoms of vaginal atrophy among
postmenopausal women was recently reported in Finland and United States [3].
The average age of natural menopause in Europe is between 47 and 50
years. As the life expectancy increases, most women will spend even
about one third of their life in postmenopausal state [1].
Estrogen
is important for the structure of urogenital area, where it maintains
the levels of collagen and elastic fibers and affects acidic
mucopolysaccharides and hyaluronic acid, necessary for tissue moisture
and epithelial barrier [1] and [2]. Estrogen promotes vaginal secretions, epithelial proliferation, vascularization and glycogen deposition in cells [2].
Exfoliating glycogen loaded superficial cells enhance the growth of
lactobacilli producing lactic acid, important for the normal acidic
vaginal pH [1]. The standard treatment for vaginal atrophy is estrogen, either topically or via
systemic route. Though effective, this is not suitable for breast
cancer patients. Also many healthy women are not willing to use hormone
replacement therapy due to its association with higher risk of breast
and endometrial cancer and venous thromboembolism [1], [4] and [5].
Sea buckthorn (Hippophaë rhamnoides) oil has in the Central Asia traditionally been used for the treatment of inflammations in the genital organs and uterus [6].
Intake of sea buckthorn (SB) oil produced with a supercritical carbon
dioxide extraction process has in clinical studies shown beneficial
effects on serum lipids and lipoproteins [7], dry eye [8], markers of endothelial inflammation [9], and platelet aggregation [10].
In a double-blind, randomized, cross-over study in women suffering from
Sjögren's syndrome, SB oil relieved the dryness-associated symptoms of
genital mucous membranes [11]. The objective of this study was to investigate the effects of oral SB oil on vaginal atrophy among post-menopausal women.
2. Participants and methods
2.1. Study design and participants
This
randomized, double-blind, placebo-controlled study was carried out at
the Gynecological Center of Turku, a private clinic in Turku, Finland
during a period from October 2012 to March 2013. The study protocol was
approved by the Ethics Committee of the Hospital District of Southwest
Finland and registered at clinicaltrials.gov (NCT01697085).
A total of 116 postmenopausal women, recruited by announcements in
local newspapers, were randomized to SB and placebo groups. Inclusion
criteria were: age of 55–75 years and experience of moderate or severe
dryness/burning/itching of vaginal mucous membranes. Exclusion criterion
was the use of systemic or local estrogen treatment. The participants
were advised not to use other oil supplements during the study and the
wash-out period of one month before the trial. They attended two study
visits: at baseline, and at three months when the intervention ended. In
addition, they were interviewed by the study gynecologist at halfway of
the intervention.
The flow of participants is presented in Fig. 1. The characteristics of participants at baseline visit are presented in Table 1.
The main outcomes were the effects of SB oil on the vaginal pH,
moisture and health, and the symptoms of vaginal atrophy. As secondary
measures, also the effects on vasomotor and psychological symptoms
associated with menopause, on skin and other mucous membranes and on
serum markers associated with cardiovascular disease and metabolic
syndrome were investigated.
- Fig. 1.
Flow of participants during the study.
- Table 1. Characteristics of the ITT participants at baseline visit.a
SBb PL Age, y 64 (5) 62 (5) BMI, kg/m2 27 (4) 27 (5) Time from last periods, mo 166 (94) 167 (107) Experience of vaginal symptoms, n (%) Dryness None 0 (0) 0 (0) Mild 24 (45) 14 (28) Moderate 23 (43) 27 (53) Severe 6 (11) 10 (20) Burning None 11 (22) 13 (26) Mild 21 (41) 17 (34) Moderate 18 (35) 20 (40) Severe 1 (2) 0 (0) Itching None 11 (22) 12 (25) Mild 24 (48) 20 (41) Moderate 14 (28) 15 (31) Severe 1 (2) 2 (4) Smoking, n (%) 5 (9) 4 (8) Previous use of systemic estrogen medication, n (%) 32 (64) 20 (42) Previous use of topical estrogen medication, n (%) 26 (50) 27 (55) Diagnosed chronic illness or condition requiring medication, n (%) c 31 (61) 25 (52) -
- a
- Values are means (SD) or n (%) of participants.
- b
- SB, n = 47–55; PL, n = 48–53.
- c
- The most common chronic illnesses or conditions requiring medication in both study groups were hypertension or elevated serum lipid levels (SB n = 14; PL n = 20), and hypo/hyperactivity of the thyroid gland (SB n = 12, PL n = 9). Four participants in the SB group and two in the placebo group had breast cancer that was being treated or had been treated before.
2.2. Study products
Participants
consumed 3 g of SB or placebo oil daily in the form of 3 capsules twice
a day. The dose was chosen based on our previous study with Sjögren's
syndrome patients [11].
The capsules shells were opaque vegetable capsules with identical
outlook. The SB oil used in the study was a standardized mixture of SB
berry and seed oils produced using supercritical carbon dioxide
extraction by Aromtech Ltd (Tornio, Finland). The main fatty acids in SB
oil were palmitoleic [16:1n − 7, 24% of fatty acids (w/w)], palmitic (16:0, 22%), linoleic (18:2n − 6, 18%), oleic (18:1n − 9, 16%), α-linolenic (18:3n − 3, 13%) and cis-vaccenic (18:1n − 7,
6%) acids. The oil contained 0.11% carotenoids (mainly β-carotene,
0.09% of the oil) and 0.44% vitamin E. Phytosterols composed 1.0% of the
SB oil, analyzed as free sterols. The placebo oil was triacylglycerols
of medium chain fatty acids fractionated from palm and coconut oils. The
main fatty acids were caprylic (8:0, 60%) and capric acid (10:0, 40%).
No vitamin E compounds were detected and the carotenoids were below the
limit of quantification. Methods for the analysis of oils are presented
in the Supplementary material.
2.3. Effects on vaginal mucous membranes
Vaginal
mucous membranes were evaluated by the same gynecologist at the
beginning and end of the intervention. Vaginal elasticity, epithelial
integrity, moisture and fluid volume were scored from 1 to 5 according
to Bachmann et al. [12].
pH of the vaginal wall was measured using a pH meter (Flexilog, Model
No 2000, Oakfield Instruments Ltd., Oxon, UK). For the analysis of
vaginal health index (VagHI), the pH was scored from 1 to 5 [12].
A higher value in VagHI, calculated as a sum of scores for elasticity,
epithelial integrity, moisture, fluid volume and pH-scores, indicates
less atrophy [12].
The vaginal moisture was assessed by measuring the length of wetting a
Schirmer paper applied on the vaginal wall for 1 min (mm/min) [13]. The vaginal maturation index (MI) was evaluated from Pap smear from a random sample of 30 participants (SB, n = 15; placebo, n = 15).
In MI, the presence of superficial cells indicates the estrogenic
influence while the presence of parabasal cells only is the sign of the
absence of that.
