Abstract
STUDY QUESTION
What are the respective roles of polycystic ovary syndrome (PCOS), long-term weight gain and obesity for the development of prediabetes or Type 2 diabetes mellitus (T2DM) by ...age 46 years?
SUMMARY ANSWER
The risk of T2DM in women with PCOS is mainly due to overweight and obesity, although these two factors have a synergistic effect on the development of T2DM.
WHAT IS KNOWN ALREADY
PCOS is associated with an increased risk of prediabetes and T2DM. However, the respective roles of PCOS per se and BMI for the development of T2DM have remained unclear.
STUDY DESIGN, SIZE, DURATION
In a prospective, general population-based follow-up birth cohort 1966 (n = 5889), postal questionnaires were sent at ages 14 (95% answered), 31 (80% answered) and 46 years (72% answered). Questions about oligoamenorrhoea and hirsutism were asked at age 31 years, and a question about PCOS diagnosis at 46 years. Clinical examination and blood sampling were performed at 31 years in 3127 women, and at 46 years in 3280 women. A 2-h oral glucose tolerance test (OGTT) was performed at 46 years of age in 2780 women.
PARTICIPANTS/MATERIALS, SETTING, METHODS
Women reporting both oligoamenorrhoea and hirsutism at age 31 years and/or diagnosis of PCOS by 46 years were considered as women with PCOS (n = 279). Women without any symptoms at 31 years and without PCOS diagnosis by 46 years were considered as controls (n = 1577). The level of glucose metabolism was classified according to the results of the OGTT and previous information of glucose metabolism status from the national drug and hospital discharge registers.
MAIN RESULTS AND THE ROLE OF CHANCE
PCOS per se significantly increased the risk of T2DM in overweight/obese (BMI ≥ 25.0 kg/m2) women with PCOS when compared to overweight/obese controls (odds ratio: 2.45, 95% CI: 1.28–4.67). Normal weight women with PCOS did not present with an increased risk of prediabetes or T2DM. The increase in weight between ages 14, 31 and 46 years was significantly greater in women with PCOS developing T2DM than in women with PCOS and normal glucose tolerance, with the most significant increase occurring in early adulthood (between 14 and 31 years: median with 25%; 75% quartiles: 27.25 kg 20.43; 34.78 versus 13.80 kg 8.55; 20.20, P < 0.001).
LIMITATIONS, REASONS FOR CAUTION
The diagnosis of PCOS was based on self-reporting, and the questionnaire at 46 years did not distinguish between polycystic ovaries only in ultrasonography and the syndrome. Ovarian ultrasonography was not available to aid the diagnosis of PCOS.
WIDER IMPLICATIONS OF THE FINDINGS
These results emphasize weight management already during adolescence and early adulthood to prevent the development of T2DM in women with PCOS, as the period between 14 and 31 years seems to be a crucial time-window during which the women with PCOS who are destined to develop T2DM by 46 years of age experience a dramatic weight gain. Furthermore, our results support the view that, particularly in times of limited sources of healthcare systems, OGTT screening should be targeted to overweight/obese women with PCOS rather than to all women with PCOS.
STUDY FUNDING/COMPETING INTEREST(S)
Finnish Medical Foundation; North Ostrobothnia Regional Fund; Academy of Finland (project grants 104781, 120315, 129269, 1114194, 24300796, Center of Excellence in Complex Disease Genetics and SALVE); Sigrid Juselius Foundation; Biocenter Oulu; University Hospital Oulu and University of Oulu (75617); Medical Research Center Oulu; National Institute for Health Research (UK); National Heart, Lung, and Blood Institute (grant 5R01HL087679-02) through the STAMPEED program (1RL1MH083268-01); National Institute of Health/National Institute of Mental Health (5R01MH63706:02); ENGAGE project and grant agreement HEALTH-F4-2007–201413; EU FP7 EurHEALTHAgeing-277849 European Commission and Medical Research Council, UK (G0500539, G0600705, G1002319, PrevMetSyn/SALVE) and Medical Research Center, Centenary Early Career Award. The authors have no conflicts of interests.
TRIAL REGISTRATION NUMBER
N/A.
Please cite this paper as: Ijäs H, Vääräsmäki M, Morin‐Papunen L, Keravuo R, Ebeling T, Saarela T, Raudaskoski T. Metformin should be considered in the treatment of gestational diabetes: a ...prospective randomised study. BJOG 2011;118:880–885.
Objective To examine if oral metformin is as effective as insulin in the prevention of fetal macrosomy in pregnancies complicated with gestational diabetes mellitus (GDM).
Design Open‐label prospective randomised controlled study.
Setting Maternity outpatient clinics in a secondary and tertiary level hospital in Finland.
Sample One hundred women with GDM who did not attain euglycaemia with diet.
Methods Women were randomised to therapy with insulin (n = 50) or oral metformin (n = 50).
Main outcome measures Incidence of large‐for‐gestational‐age (LGA) infants and neonatal morbidity.
Results There were no statistically significant differences in the incidence of LGA (8.5 versus 10.0%, P = 0.97), mean birthweight, mean cord artery pH or neonatal morbidity between the insulin and metformin groups. Fifteen (31.9%) of the 47 women randomised to metformin needed supplemental insulin. They were more obese (with a body mass index of 36 versus 30 kg/m2, P = 0.002), had higher fasting blood glucose levels in an oral glucose tolerance test (6.1 versus 5.0 mmol/l, P = 0.001) and needed medical treatment for GDM earlier (26 versus 31 gestational weeks, P = 0.002) than women who were normoglycemic with metformin. There was a tendency to a higher rate of caesarean sections in the metformin group than in the insulin group (RR 1.9; 95% CI 0.99–3.71).
Conclusions Metformin seems to be suitable for the prevention of fetal macrosomy, especially in lean or moderately overweight women developing GDM in late gestation. Women with considerable obesity, high fasting blood glucose and an early need for pharmacological treatment may be more suitable for insulin therapy.
Adiposity rebound (AR), the second BMI rise in childhood at around the age of 6 years, is associated with obesity and metabolic alteration in later life. Given that polycystic ovary syndrome (PCOS) ...has a strong metabolic component, early life growth patterns could reveal a risk of PCOS. Thus, we aimed to investigate the associations between age at AR and PCOS diagnosis and BMI later in life.
This study is part of a prospective, population-based longitudinal study, where women with PCOS diagnosis by age 46 (n = 280) were compared with asymptomatic women (CTRLs, n = 1573). Weight and height data from birth to age 13 years, at age at menarche, and at ages 31 and 46 years were analyzed RESULTS: Women with PCOS had lower birth weight (3357 ± 477 vs. 3 445 ± 505 g, p < 0.001), earlier age at AR (5.2 ± 1.0 vs. 5.6 ± 0.90 years, p < 0.001) and higher BMI from AR onwards compared with controls. Early timing of AR was associated with PCOS diagnosis independently of BMI (OR 1.62, 95% Cl 1.37-1.92). Women with PCOS and early AR had higher BMI at 31 and 46 years when compared to controls with early AR. The age at AR did not associate with T levels at ages 31 or 46 years.
Early AR was associated with PCOS diagnosis and high BMI in adulthood. Adolescent girls with early AR and persisting obesity should be screened for PCOS symptoms, such as persistent irregular cycles and hirsutism.
Polycystic ovary syndrome (PCOS) is a common reproductive disorder associated with metabolic disturbances including obesity, insulin resistance and diabetes mellitus. Here we investigate whether ...changes in the metabolic profile of PCOS women are driven by increased tendency to obesity or are specific features of PCOS related to increased testosterone levels.
We conducted an NMR metabolomics association study of PCOS cases (n=145) and controls (n=687) nested in a population-based birth cohort (n=3127). Subjects were 31 years old at examination. The main analyses were adjusted for waist circumference (WC) as a proxy measure of central obesity. Subsequently, metabolite concentrations were compared between cases and controls within pre-defined WC strata. In each stratum, additional metabolomics association analyses with testosterone levels were conducted separately among cases and controls.
Overall, women with PCOS showed more adverse metabolite profiles than the controls. Four lipid fractions in different subclasses of very low density lipoprotein (VLDL) were associated with PCOS, after adjusting for WC and correction for multiple testing (P<0.002). In stratified analysis the PCOS women within large WC strata (⩾98 cm) had significantly lower high density lipoprotein (HDL) levels, Apo A1 and albumin values compared with the controls. Testosterone levels were significantly associated with VLDL and serum lipids in PCOS cases with large WC but not in the controls. The higher testosterone levels, adjusted for WC, associated adversely with insulin levels and HOMA IR in cases but not in the controls.
Our findings show that both abdominal obesity and hyperandrogenism contribute to the dyslipidaemia and other metabolic traits of PCOS which all may negatively contribute to the long-term health of women with PCOS.
STUDY QUESTIONS
Can serum anti-Müllerian hormone (AMH) levels measured in female adolescents predict polycystic ovary syndrome (PCOS)-associated features in adolescence and early adulthood?
SUMMARY ...ANSWER
AMH levels associated well with PCOS-associated features (such as testosterone levels and oligoamenorrhoea) in adolescence, but was not an ideal marker to predict PCOS-associated features in early adulthood.
WHAT IS KNOWN ALREADY
Several studies have reported that there is a strong correlation between antral follicle count and serum AMH levels and that women with PCOS/PCO have significantly higher serum AMH levels than women with normal ovaries. Other studies have reported an association between AMH serum levels and hyperandrogenism in adolescence, but none has prospectively assessed AMH as a risk predictor for developing features of PCOS during adulthood.
STUDY DESIGN, SIZE, DURATION
A subset of 400 girls was selected from the prospective population-based Northern Finland Birth Cohort 1986 (n = 4567 at age 16 and n = 4503 at age 26). The population has been followed from 1986 to the present.
PARTICIPANTS/MATERIAL, SETTING, METHODS
At age 16, 400 girls (100 from each testosterone quartile: 50 with oligo- or amenorrhoea and 50 with a normal menstrual cycle) were selected at random from the cohort for AMH measurement. Metabolic parameters were also assessed at age 16 in all participants. Postal questionnaires enquired about oligo- or amenorrhoea, hirsutism, contraceptive use and reproductive health at ages 16 and 26.
MAIN RESULTS AND ROLE OF CHANCE
There was a significant correlation between AMH and testosterone at age 16 (r = 0.36, P < 0.001). AMH levels at age 16 were significantly higher among girls with oligo- or amenorrhoea compared with girls with normal menstrual cycles (35.9 pmol/l 95% CI: 33.2;38.6 versus 27.7 pmol/l 95% CI: 25.0;30.4, P < 0.001). AMH at age 16 was higher in girls who developed hirsutism at age 26 compared with the non-hirsute group (31.4 pmol/l 95% CI 27.1;36.5 versus 25.8 pmol/l 95% CI 23.3;28.6, P = 0.036). AMH at age 16 was also higher in women with PCOS at age 26 compared with the non-PCOS subjects (38.1 pmol/l 95% CI 29.1;48.4 versus 30.2 pmol/l 95% CI 27.9;32.4, P = 0.044). The sensitivity and specificity of the AMH (cut-off 22.5 pmol/l) for predicting PCOS at age 26 was 85.7 and 37.5%, respectively. The addition of testosterone did not significantly improve the accuracy of the test. There was no significant correlation between AMH levels and metabolic indices at age 16.
IMPLICATIONS, REASONS FOR CAUTION
AMH is related to oligo- or amenorrhoea in adolescence, but it is not a good marker for metabolic factors. The relatively low rate of participation in the questionnaire at age 26 may also have affected the results. AMH was measured in a subset of the whole cohort. AMH measurement is lacking international standardization and therefore the concentrations and cut-off points are method dependent.
WIDER IMPLICATIONS FOR THE FINDINGS
Using a high enough cut-off value of AMH to predict which adolescents are likely to develop PCOS in adulthood could help to manage the condition from an early age due to a good sensitivity. However, because of its low specificity, it is not an ideal diagnostic marker, and its routine use in clinical practice cannot, at present, be recommended.
STUDY FUNDINGS AND COMPETING INTERESTS
The study was funded by a grant from Wellcome Trust (089549/Z/09/Z) to H.L., S.F. and M.-R.J. Study funding was also received from Oulu University Hospital Research Funds, Sigrid Juselius Foundation and the Academy of Finland. None of the authors have any competing interest to declare.
Abstract
STUDY QUESTION
What is the association between childhood and adolescent BMI and reproductive capacity in women?
SUMMARY ANSWER
Adolescent girls with obesity had an increased risk of ...infertility and childlessness in adulthood independently of their marital status or the presence of polycystic ovary syndrome (PCOS).
WHAT IS KNOWN ALREADY
Girls with obesity (BMI (kg/m2)>95th percentile) more often exhibit menstrual irregularities and infertility problems as compared to those with normal weight, and premenarcheal girls with obesity have an increased risk of childlessness and infertility in adulthood. Follow-up studies on the relation between childhood and adolescence growth patterns and fertility or parity throughout the reproductive life span are limited.
STUDY DESIGN, SIZE, DURATION
A prospective, population-based cohort study (the Northern Finland birth cohort 1966) was performed with 5889 women born in 1966 and followed from birth to age 50 years. Postal questionnaires at ages 31 and 46 years addressed questions on reproductive capacity evaluated by decreased fecundability, need for infertility assessment and treatment by 46 years of age. Childlessness and number of children by age 50 years were recovered from registers. Women who did not report ever having attempted to achieve pregnancy (n = 1507) were excluded. The final study population included 4382 women who attempted to achieve pregnancy before age 46 years.
PARTICIPANTS/MATERIALS, SETTING, METHODS
Data on BMI were collected by trained personnel at all stages. We assessed association with both prospectively measured BMI at various time points and with early adiposity phenotypes derived from linear mixed models including the timing and the BMI at adiposity peak (AP) and adiposity rebound (AR). Self-reported infertility assessments and treatments were assessed at ages 31 and 46 years. Data on deliveries were collected from the national birth register. Decreased fecundability was defined at age 31 years as time to achieve pregnancy over 12 months. Logistic regression analyses were conducted with adjustments for marital status, education level and smoking at age 31 years. Women with PCOS were excluded from stratification-based sensitivity analyses. Obesity at a specific age group was defined by having at least one BMI value above the 95th percentile during the related period.
MAIN RESULTS AND THE ROLE OF CHANCE
BMI at the age of AR (5–7 years) was not associated with fertility outcomes after adjustments, but girls with AR <5.1 years had a higher risk of remaining childless compared to girls with AR over 5.1 years (adjusted odds ratio (OR): 1.45 (1.10–1.92)). At ages 7–10 and 11–15 years, obesity was associated with decreased fecundability (adjusted OR 2.05 (1.26–3.35) and 2.04 (1.21–3.44), respectively) and a lower number of children. At age 11–15 years, both overweight and obesity were associated with a higher risk of childlessness (adjusted OR 1.56 (1.06–2.27), 1.77 (1.02–3.07), respectively), even after excluding women with PCOS. Underweight at age 11–15 years was associated with an increased risk for infertility treatment (adjusted OR 1.55 (1.02–2.36)) and a tendency for an increased risk for infertility assessment (adjusted OR 1.43 (0.97–2.10)) after excluding women with PCOS.
LIMITATIONS, REASON FOR CAUTION
Despite a high participation rate throughout the follow-up, some growth data for children over the different age groups were missing. Infertility outcomes were self-reported. A potential over-diagnosis of obesity may have reduced the significance of the association between childhood obesity and fertility outcomes, and the diagnosis of PCOS was self-reported.
WIDER IMPLICATIONS OF THE FINDINGS
This study supports previous results showing that girls with obesity in late childhood and in adolescence displayed reduced fertility and an increased risk of remaining childless in adulthood, independently of marital history and PCOS in adulthood. These findings corroborate the body of evidence for a causal relation between early adiposity and the reproductive functions in women. We recommend reinforcing the prevention of obesity in school-age girls to reduce the risk of impaired reproductive functions.
STUDY FUNDING/COMPETING INTEREST(S)
NFBC1966 received financial support from University of Oulu Grant no. 65354, Oulu University Hospital Grant no. 2/97, 8/97, Ministry of Health and Social Affairs Grant no. 23/251/97, 160/97, 190/97, National Institute for Health and Welfare, Helsinki Grant no. 54121, Regional Institute of Occupational Health, Oulu, Finland Grant no. 50621, 54231. The Finnish Medical Foundation, the North Ostrobothnia Regional Fund, the Academy of Finland (project grants 315921, 104781, 120315, 129269, 1114194, 24300796), Center of Excellence in Complex Disease Genetics and SALVE, the Sigrid Juselius Foundation, Biocenter Oulu, University Hospital Oulu and University of Oulu (75617), Jalmari ja Rauha Ahokkaan säätiö, The Finnish Medical Foundation, Medical Research Center Oulu, National Institute for Health Research (UK). M. R. J., S. S. and R. N. received funding by the Academy of Finland (#268336) and the European Union’s Horizon 2020 research and innovation program (under Grant agreement no. 633595 for the DynaHEALTH action and GA 733206 for LifeCycle). The funders had no role in study design, in the collection, analysis and interpretation of the data, in the writing of the article and in the decision to submit it for publication. The authors have no conflict of interest to disclose.
TRIAL REGISTRATION NUMBER
N/A.
How does the gut bacteriome differ based on mood disorders (MDs) in women with polycystic ovary syndrome (PCOS), and how can the gut bacteriome contribute to the associations between these two ...conditions?
Women with PCOS who also have MDs exhibited a distinct gut bacteriome with reduced alpha diversity and a significantly lower abundance of Butyricicoccus compared to women with PCOS but without MDs.
Women with PCOS have a 4- to 5-fold higher risk of having MDs compared to women without PCOS. The gut bacteriome has been suggested to influence the pathophysiology of both PCOS and MDs.
This population-based cohort study was derived from the Northern Finland Birth Cohort 1966 (NFBC1966), which includes all women born in Northern Finland in 1966. Women with PCOS who donated a stool sample at age 46 years (n = 102) and two BMI-matched controls for each case (n = 205), who also responded properly to the MD criteria scales, were included.
A total of 102 women with PCOS and 205 age- and BMI-matched women without PCOS were included. Based on the validated MD criteria, the subjects were categorized into MD or no-MD groups, resulting in the following subgroups: PCOS no-MD (n = 84), PCOS MD (n = 18), control no-MD (n = 180), and control MD (n = 25). Clinical characteristics were assessed at age 31 years and age 46 years, and stool samples were collected from the women at age 46 years, followed by the gut bacteriome analysis using 16 s rRNA sequencing. Alpha diversity was assessed using observed features and Shannon's index, with a focus on genera, and beta diversity was characterized using principal components analysis (PCA) with Bray-Curtis Dissimilarity at the genus level. Associations between the gut bacteriome and PCOS-related clinical features were explored by Spearman's correlation coefficient. A P-value for multiple testing was adjusted with the Benjamini-Hochberg false discovery rate (FDR) method.
We observed changes in the gut bacteriome associated with MDs, irrespective of whether the women also had PCOS. Similarly, PCOS MD cases showed a lower alpha diversity (Observed feature, PCOS no-MD, median 272; PCOS MD, median 208, FDR = 0.01; Shannon, PCOS no-MD, median 5.95; PCOS MD, median 5.57, FDR = 0.01) but also a lower abundance of Butyricicoccus (log-fold changeAnalysis of Compositions of Microbiomes with Bias Correction (ANCOM-BC)=-0.90, FDRANCOM-BC=0.04) compared to PCOS no-MD cases. In contrast, in the controls, the gut bacteriome did not differ based on MDs. Furthermore, in the PCOS group, Sutterella showed positive correlations with PCOS-related clinical parameters linked to obesity (BMI, r2=0.31, FDR = 0.01; waist circumference, r2=0.29, FDR = 0.02), glucose metabolism (fasting glucose, r2=0.46, FDR < 0.001; fasting insulin, r2=0.24, FDR = 0.05), and gut barrier integrity (zonulin, r2=0.25, FDR = 0.03).
Although this was the first study to assess the link between the gut bacteriome and MDs in PCOS and included the largest PCOS dataset for the gut microbiome analysis, the number of subjects stratified by the presence of MDs was limited when contrasted with previous studies that focused on MDs in a non-selected population.
The main finding is that gut bacteriome is associated with MDs irrespective of the PCOS status, but PCOS may also modulate further the connection between the gut bacteriome and MDs.
This research was funded by the European Union's Horizon 2020 Research and Innovation Programme under the Marie Sklodowska-Curie Grant Agreement (MATER, No. 813707), the Academy of Finland (project grants 315921, 321763, 336449), the Sigrid Jusélius Foundation, Novo Nordisk Foundation (NNF21OC0070372), grant numbers PID2021-12728OB-100 (Endo-Map) and CNS2022-135999 (ROSY) funded by MCIN/AEI/10.13039/501100011033 and ERFD A Way of Making Europe. The study was also supported by EU QLG1-CT-2000-01643 (EUROBLCS) (E51560), NorFA (731, 20056, 30167), USA/NIH 2000 G DF682 (50945), the Estonian Research Council (PRG1076, PRG1414), EMBO Installation (3573), and Horizon 2020 Innovation Grant (ERIN, No. EU952516). The funders did not participate in any process of the study. We have no conflicts of interest to declare.
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STUDY QUESTION
Do teenage girls with a history of menstrual irregularity and/or elevated androgen levels in adolescence exhibit an increased risk of polycystic ovary syndrome (PCOS) and/or ...infertility later on in adulthood?
SUMMARY ANSWER
Our results suggest that menstrual irregularity and/or elevated androgen levels at 16 years are still associated with symptoms of PCOS at 26 years as well as infertility problems at 26 years but not with decreased pregnancy or delivery rates at 26 years.
WHAT IS KNOWN ALREADY
Hyperandrogenaemia is associated with menstrual irregularity, hirsutism, acne and potentially higher risk for PCOS, but there are few follow-up studies investigating whether adolescent hyperandrogenaemia and/or menstrual irregularity are an early sign of PCOS.
STUDY DESIGN, SIZE, DURATION
A prospective population-based cohort study was conducted using two postal questionnaires targeting girls in the Northern Finland Birth Cohort 1986 (NFBC1986, n = 4567). The NFBC1986 comprises all expected births from the year 1986 in the two northernmost provinces of Finland. Collection of the database was performed at the age of 16 and 26. The 16-year and 26-year questionnaires included one question about the regularity and length of the menstrual cycle. The 26-year questionnaire also included questions about symptoms of PCOS, reproduction and infertility problems.
PARTICIPANTS, SETTING, METHODS
The response rates for the questionnaires were 80% (n = 3669) at 16 years and 50% (n = 2270) at 26 years. At 15–16 years, of 2448 girls, 709 (29%) girls reported menstrual irregularity (symptomatic girls) and 1739 (71%) had regular periods (non-symptomatic girls). After combining data from the two questionnaires a total of 2033 girls were included in the analyses. The χ2 and Student's t-test was used to compare reproductive outcome and prevalence of clinical hyperandrogenaemia, PCOS and infertility at 26 years between the study groups. Univariate and multivariate logistic regression models were employed to estimate the association of menstrual irregularity at 16 years with clinical hyperandrogenaemia, PCOS and infertility at 26 years.
MAIN RESULTS AND THE ROLE OF CHANCE
At follow-up, the proportion of symptomatic girls who had conceived at least once (68.0 versus 67.9%) and had delivered at least one child (25.7 versus 28.1%) was similar to the non-symptomatic women and the groups had similar miscarriage rates (11.6 versus 12.1%). Logistic regression analyses indicated that menstrual irregularity at 16 years was associated with an increased risk of menstrual irregularity adjusted odds ratio (OR) 1.37, 95% confidence interval (CI) 1.00–1.88, P = 0.050, PCOS (adjusted OR 2.91, 95% CI 1.74–4.84, P < 0.001) and infertility problems (adjusted OR 2.07, 95% CI 1.16–3.76, P = 0.013) at 26 years. At 26 years, women with PCOS (P = 0.013), hirsutism (P = 0.001) and acne (P < 0.001) exhibited significantly higher values of free androgen index (FAI) at 16 years than control women. There was a significant linear trend in the higher FAI quartiles at 16 years towards higher prevalence of PCOS (P = 0.005), hirsutism (P < 0.001) and acne (P < 0.001) at 26 years. Only 10.5% of the girls with menstrual irregularity at 16 years had PCOS at 26 years.
LIMITATIONS, REASONS FOR CAUTION
The diagnosis of menstrual irregularity was based on a self-reported questionnaire, thus introducing a risk of information bias in reporting the symptoms. Moreover, ovarian ultrasonography was not available to aid the diagnosis of PCOS and there was no clinical evaluation of hyperandrogenism. The relatively low rate of participation to the questionnaire at 26 years may also have biased the results.
WIDER IMPLICATIONS OF THE FINDINGS
Our findings confirm that menstrual irregularity and/or elevated androgen levels are already present in adolescence in women with PCOS and infertility in later life, which strengthens the importance of early identification of menstrual irregularity.
STUDY FUNDING/COMPETING INTEREST(S)
This work was supported by grants from the Finnish Medical Society Duodecim, the North Ostrobothnia Regional Fund, the Academy of Finland, the Sigrid Juselius Foundation, University Hospital Oulu and University of Oulu, the European Commission and the Medical Research Council, UK, Welcome Trust (089549/Z/09/Z). None of the authors have any conflict of interest.
STUDY QUESTION
What is the effect of alternative administration routes of combined contraceptives (CCs) on androgen secretion, chronic inflammation, glucose tolerance and lipid profile?
SUMMARY ...ANSWER
The use of oral, transdermal and vaginal CCs impairs glucose tolerance and induces chronic inflammation.
WHAT IS KNOWN AND WHAT THIS PAPER ADDS
Oral CCs worsen insulin sensitivity and are associated with increased levels of circulating inflammatory markers, whereas the metabolic effects of transdermal and vaginal CCs have been reported to be minimal. This is the first study comparing three different administration routes of CCs on metabolic variables.
STUDY DESIGN, SIZE AND DURATION
This randomized (computer-generated) open-label 9-week follow-up study was conducted at the Oulu University Hospital, Finland. Fasting blood samples were collected at baseline and thereafter at 5 and 9 weeks of treatment, and serum levels of 17-hydroxyprogesterone, androstenedione, testosterone, C-reactive protein (CRP), sex hormone-binding globulin (SHBG), glucose, insulin, C-peptide, total, low-density lipoprotein and high-density lipoprotein cholesterol and triglycerides were measured. Oral glucose tolerance tests were performed and plasma levels of pentraxin 3 (PTX-3) were measured at 0 and 9 weeks. The randomization list, with an allocation ratio of 1:1:1 and block size of six, was computer generated and constructed by a pharmacist at the Oulu University Hospital. The research nurse controlled the randomization list and assigned participants to their groups at the first visit.
PARTICIPANTS AND SETTING
Forty-two of 54 healthy women who entered the study used oral contraceptive pills (n = 13), transdermal contraceptive patches (n = 15) or contraceptive vaginal rings (n = 14) continuously for 9 weeks. Inclusion criteria were regular menstrual cycles, at least a 2-month washout as regards hormonal contraceptives and no medication.
MAIN RESULTS AND THE ROLE OF CHANCE
Serum levels of SHBG increased and consequently the free androgen index (FAI) decreased in all study groups from baseline to 9 weeks of treatment FAI, oral: 1.3 (95% confidence interval, CI: 0.94; 1.62) to 0.40 (0.25; 0.54); transdermal: 1.2 (0.96; 1.4) to 0.36 (0.30; 0.43); vaginal: 1.6 (1.1; 2.1) to 0.43 (0.29; 0.58), P < 0.001 in all groups. Insulin sensitivity was reduced at 9 weeks in all three groups according to the Matsuda index oral: 7.3 (5.5; 9.0) to 5.6 (3.9; 7.3); transdermal: 9.1 (6.7; 11.4) to 6.6 (4.5; 8.8); vaginal: 7.7 (5.9; 9.5) to 5.4 (3.9; 7.0), P= 0.004–0.024. Levels of HDL cholesterol, triglycerides and CRP rose in all three groups CRP, oral: 0.70 (0.38; 1.0) to 5.4 (1.0; 9.9) mg/l; transdermal: 0.77 (0.45; 1.1) to 2.9 (1.4;4.4) mg/l; vaginal: 0.98 (0.52; 1.4) to 3.7 (−0.25; 7.7, a negative value due to skewed distribution to right) mg/l, P≤ 0.002 in all groups and PTX-3 levels increased in the oral and transdermal study groups (P = 0.007 and P = 0.002).
WIDER IMPLICATIONS OF THE FINDINGS
Although the long-term consequences of the present results remain undetermined, these findings emphasize the importance of monitoring glucose metabolism during the use of CCs, especially in women with known risks of type 2 diabetes or cardiovascular diseases.
BIAS, LIMITATIONS, GENERALIZABILITY
The number of subjects was relatively low. Moreover, the 9-week exposure to CCs is too short to draw conclusions about the long-term health consequences. However, as the subjects were healthy, normal-weight young women, the possible alterations in the glucose and inflammatory profiles among women with known metabolic risks might be even greater.
STUDY FUNDING/COMPETING INTERESTS
This work was supported by grants from the Academy of Finland, the Sigrid Jusélius Foundation, the Finnish Medical Foundation, the Research Foundation of Obstetrics and Gynecology, Oulu University Scholarship Foundation, the North Ostrobothnia Regional Fund of the Finnish Cultural Foundation, the Tyyni Tani Foundation of the University of Oulu and the Finnish-Norwegian Medical Foundation. No competing interests.
TRIAL REGISTRATION NUMBER
NCT01087879.