Pregnancy complications in infertile patients with polycystic ovary syndrome: updated evidence

Placentation and complications of ART pregnancy. An update on the different possible etiopathogenic mechanisms involved in the development of obstetric complications

INTRODUCTION

Infertile couples' percentage is increasing all over the world, especially in Italy, with high number of children born in our country through assisted reproductive techniques (ART). However, pregnancies obtained by ART have increased potential obstetrical risks which could be caused by fetus-placenta unit development, most of all due to placentation's evolution. These can be reassumed into miscarriage, chromosomal abnormalities, preterm delivery, multiple pregnancy, IUGR, placenta previa, abruptio placentae, preeclampsia and hypertensive disorders, postpartum hemorrhage.

METHODS

The aim of this article is to evaluate hypothetic mechanism involved in placentation process and in the etiopathology of ART pregnancies disorders, giving an updating overview of different etiopathogenetic pathways and features. On this scenario, we create an updated review about the etiopathogenesis of abnormal placentation in ART pregnancies.

RESULTS

Several features and different etiopathogenetic characteristic might impact differently such as advanced maternal age, poor ovarian reserve, oocyte quality and causes of subfertility themselves, and the ART techniques itself, as hormonal medical treatments and laboratory techniques such as gamete and embryo laboratory culture, cryopreservation versus fresh ET, number of embryos transferred.

CONCLUSION

To further explore the molecular mechanisms behind placentation in ART pregnancies, further studies are necessary to gain a better understanding of the various aspects involved, particularly those which are not fully comprehended. This could prove beneficial to clinicians in both ART care and obstetric care, as it could help to stratify obstetrical risk and decrease complications in women undergoing ART, as well as perinatal disorders in their children. Correct placentation is essential for a successful pregnancy for both mother and baby.

Increased Prevalence of Adverse Health Outcomes Across the Lifespan in Those Affected by Polycystic Ovary Syndrome: A Canadian Population Cohort

Background

Polycystic ovary syndrome (PCOS) is the most common metabolic-endocrine disorder impacting the health and quality of life of women over the lifespan. Evidence-based data on the scope of adverse health outcomes in those affected by PCOS is critical to improve healthcare and quality of life in this population. The aim of this study was to determine the prevalence of adverse health outcomes in those with PCOS compared to age-matched controls.

Methods

We conducted a retrospective observational case-control study in those diagnosed with PCOS and age-matched controls using the Alberta Health Services Health Analytics database and the International Classification of Diseases, for the period from 2002-2018 in Alberta, Canada.

Results

The cohort consisted of n = 16,531 exposed PCOS cases and n = 49,335 age-matched un-exposed controls. The prevalences of hypertension, renal disease, gastrointestinal disease, eating disorders, mental illness, depression-anxiety, rheumatoid arthritis, respiratory infections, and all malignancies were 20%-40% (P < 0.0001) higher in those with PCOS, compared to controls. The prevalence of obesity, dyslipidemia, nonalcoholic fatty liver disease, and type 2 diabetes was 2-3 fold higher in those with PCOS (P < 0.001). Cardiovascular, cerebrovascular, and peripheral vascular disease were 30%-50% higher, and they occurred 3-4 years earlier in those with PCOS (P < 0.0001); a 2-fold higher prevalence of dementia occurred in those with PCOS, compared to controls.

Conclusion

These findings provide evidence that PCOS is associated with a higher prevalence of morbidities over the lifespan, and the potential scope of the healthcare burden in women affected by PCOS.

Mediating effects of DNA methylation in the association between sleep quality and infertility among women of childbearing age

BACKGROUND

This study aims to investigate the association between sleep quality and infertility among women and to explore the mediating effects of DNA methylation in this association.

METHODS

This study is a population-based case-control study. The relationship between sleep quality and infertility was investigated in women with anovulatory infertility (n = 43) and healthy controls (n = 43). Genome-wide DNA methylation was profiled from peripheral blood samples using the Illumina Infinium Human Methylation 850k BeadChip. Differentially methylated CpGs between cases and controls were identified using the ChAMP R package. The mediating effect of DNA methylation between sleep quality and infertility among women was investigated using the Bayesian estimation method provided by the R package "mediation".

RESULTS

The survey included 86 women of reproductive age, with 43 participants each in the case and control groups. The average age of the women was 27.6 ± 2.8 years (case group: 27.8 ± 3.0 years, control group: 27.4 ± 2.7 years). A total of 262 differentially methylated CpGs corresponding to 185 genes were identified. Difficulty falling asleep was a risk factor for infertility in women (OR = 3.69, 95%CI = 1.14, 11.99), and a causal mediation effect of DNA methylation CpGs was found. The mediating effect coefficient for cg08298632 was 0.10 (95%CI = 0.01-0.22), and the proportion of the total effect mediated by this methylation site increased to 64.3%.

CONCLUSION

These results suggest that DNA methylation CpGs (cg08298632) play a significant role in the relationship between difficulty falling asleep and infertility in females. These findings contribute to our understanding of the underlying mechanisms that connect difficulty falling asleep and infertility in women. Further studies are necessary to fully understand the biological significance and potential therapeutic applications of these findings. The identified DNA methylation sites provide new and valuable insights and potential targets for future studies aiming to prevent and treat female infertility.

Polycystic ovarian syndrome and miscarriage in IVF: systematic revision of the literature and meta-analysis

PURPOSE

To evaluate the risk of miscarriage in IVF cycles in women with PCOS.

METHODS

Systematic review and meta-analysis. Systematic search of MEDLINE, EMBASE and Google Scholar. The language search was restricted to English, Spanish and French, from 2000 to 2019, with crosschecking of references from relevant articles. Inclusion criteria were: (1) IVF cycles (2) a group of patients with PCOS was considered separately, (3) the miscarriage rate was reported, (4) there was a control group, (5) definition of PCOS according the Rotterdam criteria. Exclusion criteria were been excluded from the meta-analysis: (1) publication prior to the year 2000, (2) animal studies, (3) reviews, (4) abstracts or conference papers, (5) letters, (6) case reports, (7) studies comparing different IVF techniques, (8) studies comparing groups with and without metformin or other treatments, (9) studies on induced abortions. Risk of bias was assessed by the Newcastle-Ottawa score (NOS). All the included studies had a low risk of bias (NOS scores ranging 7-8). The review protocol was registered in PROSPERO (CRD42020186713). Seventeen studies were included in the meta-analysis. There was a total of 10,472 pregnancies (2650 in PCOS and 7822 in controls) of which 1885 were miscarriages (682 in PCOS and 1203 in controls). We considered the miscarriage rate (MR), preclinical MR, early MR, and late MR.

RESULTS

In IVF pregnancies the risk of miscarriage was significantly increased when considering miscarriages in total (RR = 1.59; CI = 1.45-1.75), preclinical miscarriages (RR = 1.59; CI = 1.35-1.88), and early miscarriages (RR = 1.44; CI = 1.16-1.79). The increased miscarriage rate persisted in Chinese and Western populations when considered separately. The risk of miscarriage was increased in the subgroup of fresh transfers (RR = 1.21; CI = 1.06-1.39) as well as in the subgroup including either fresh or frozen transfers (RR = 1.95; CI = 1.72-2.22).

CONCLUSION

PCOS is linked to an increased MR in IVF pregnancies both of miscarriages in total, and to an increase in preclinical and early miscarriages.

PROSPERO NUMBER

CRD42020186713.

Hormone replacement cycles are associated with a higher risk of hypertensive disorders: Retrospective cohort study in singleton and twin pregnancies

OBJECTIVE

To elaborate the associations of different cycle regimens (natural cycle [NC], stimulated cycle [SC], hormone replacement cycle [HRC]) on maternal and neonatal adverse pregnancy outcomes after frozen-thawed embryo transfers (FET).

DESIGN

Population-based registry study.

SETTING

Swiss IVF Registry.

POPULATION OR SAMPLE

Singleton (n = 4636) and twin (n = 544) live births after NC-FET (n = 776), SC-FET (n = 758) or HRC-FET (n = 3646) registered from 2014 to 2019.

METHODS

Fifteen pregnancy pathologies were modelled for singleton and twin pregnancies using mixed models adjusted for cycle regimen, delivery, fertilisation technique, chronic anovulation, age of mother and centre.

MAIN OUTCOME MEASURES

Maternal (vaginal bleeding, isolated arterial hypertension and pre-eclampsia) and neonatal (gestational age, birthweight, mode of delivery) adverse pregnancy outcomes.

RESULTS

In singleton pregnancies, the incidences of bleeding in first trimester, isolated hypertension and pre-eclampsia were highest in HRC-FET with doubled odds of bleeding in first trimester (adjusted odds ratio [aOR] 2.23; 95% CI 1.33-3.75), isolated hypertension (aOR 2.50; 95% CI 1.02-6.12) and pre-eclampsia (aOR 2.16; 95% CI 1.13-4.12) in HRC-FET vs. NC-FET and with doubled respectively sixfold odds of bleeding (aOR 2.08; 95% CI 1.03-4.21) and pre-eclampsia (6.02; 95% CI 1.38-26.24) in HRC-FET versus SC-FET. In twin pregnancies, the incidence of pre-eclampsia was highest in HRC-FET with numerically higher odds of pre-eclampsia in HRC-FET versus NC-FET and versus SC-FET.

CONCLUSIONS

Our data implied the highest maternal risks of hypertensive disorders in HRC-FET, therefore clinicians should prefer SC-FET or NC-FET if medically possible.

Anti-Müllerian Hormone and Polycystic Ovary Syndrome in Women and Its Male Equivalent

This article reviews the main findings on anti-Müllerian hormone (AMH) and its involvement in the pathogenesis of polycystic ovary syndrome (PCOS) and its male equivalent. In women, AMH is produced by granulosa cells from the mid-fetal life to menopause and is a reliable indirect marker of ovarian reserve. AMH protects follicles from atresia, inhibits their differentiation in the ovary, and stimulates gonadotrophin-releasing hormone neurons pulsatility. AMH overexpression in women with PCOS likely contributes to the increase of the follicle cohort and of androgen levels, leading to follicular arrest and anovulation. In the male, AMH is synthesized at high levels by Sertoli cells from fetal life to puberty when serum AMH falls to levels similar to those observed in women. AMH is involved in the differentiation of the genital tract during fetal life and plays a role in Sertoli and Leydig cells differentiation and function. Serum AMH is used to assess Sertoli cell function in children with disorders of sex development and various conditions affecting the hypothalamic–pituitary–testicular axis. Although the reproductive function of male relative of women with PCOS has been poorly investigated, adolescents have elevated levels of AMH which could play a detrimental role on their fertility.

Comparison of two endometrial preparation methods for frozen-thawed embryo transfer in anovulatory PCOS patients: impact on miscarriage rate

OBJECTIVE

- Some studies have suggested that patients with polycystic ovary syndrome (PCOS) are at high risk of miscarriage. However, this still remains controversial. Several potential factors might explain this association: obesity, hyperinsulinemia and hyperandrogenism. Artificial and stimulated cycles appear to be comparable for endometrial preparation in frozen-thawed embryo transfer (FET) in PCOS patients. Only a few studies have assessed miscarriage rates specifically in PCOS. We have evaluated the impact of endometrial preparation on FET outcomes in anovulatory PCOS patients.

METHODS

- A retrospective cohort study was conducted at the Lille University Hospital, including 255 FET cycles in 134 PCOS patients between January 2011 and December 2017. PCOS was defined by the presence of at least two of the three Rotterdam's criteria. Patients were under 35 years old. Two endometrial preparation protocol were studied: stimulated cycle (gonadotropins on the second day of the cycle and luteal phase support including natural progesterone 600 mg/day) and artificial cycle (6 mg oral estradiol valerate and 800 mg micronized vaginal progesterone daily).

RESULTS

- 137 FET were performed under stimulated cycle and 118 FET under artificial cycle. Early pregnancy rates (30% versus 37.3%, p = NS), miscarriage rates (22% versus 25%, p = NS) and live birth rates (23.4% versus 26.3%, p = NS) were similar.

CONCLUSIONS

- In anovulatory PCOS women, the type of endometrial preparation does not influence FET outcomes, specifically regarding the miscarriage rate.

Fundamental Concepts and Novel Aspects of Polycystic Ovarian Syndrome: Expert Consensus Resolutions

Polycystic ovary syndrome (PCOS) is a very common endocrine and metabolic disorder with the involvement of both genetic and environmental factors. Although much has been clarified on its pathogenesis, diagnosis, clinical manifestations, and therapy, there are still areas of uncertainty. To address fundamental concepts, novel aspects and hypotheses, and future perspectives, including the possible additional benefits of treatment with nutraceuticals, an expert consensus panel formed by endocrinologists and gynecologists was established. After an independent review of the literature, the panel convened electronically on February 3, 2020, and six resolutions were created, debated, and agreed upon discussion, and finally approved in their final form in a consensus livestream meeting held on April 15. The summary of the resolutions are: (1) PCOS is a well-established medical condition that negatively affects reproduction, general health, sexual health, and quality of life; (2) the symptoms and signs of PCOS appear early in life especially in female newborns from PCOS carriers; (3) women with PCOS have significantly increased risk of pregnancy-related complications including gestational diabetes mellitus; (4) a male PCOS equivalent exists, and it may impact on metabolic health and probably on reproduction; (5) the evidence supports that medical therapy for PCOS is effective, rational, and evidence-based; (6) the evidence supports a major research initiative to explore possible benefits of nutraceutical therapy for PCOS. The proposed resolutions may be regarded as points of agreement based on the current scientific evidence available.

Polycystic ovary syndrome as an independent risk factor for gestational diabetes and hypertensive disorders of pregnancy: a population-based study on 9.1 million pregnancies

STUDY QUESTION

Does polycystic ovary syndrome (PCOS) confer an independent risk for the development of gestational diabetes mellitus (GDM), gestational hypertension (GHTN) and preeclampsia (PEC) based on analysis of the Healthcare Cost and Utilization Project Nationwide Inpatient Sample (HCUP-NIS) database.

SUMMARY ANSWER

After controlling for all potential confounding effects, women with PCOS are at a 2-fold higher risk of developing GDM, a 50% increased risk for the development of GHTN and a 30% increased risk of developing PEC than women without PCOS.

WHAT IS KNOWN ALREADY

Currently, there is evidence of an increased prevalence of maternal pregnancy complications in women with PCOS. However, there remain significant gaps in understanding how PCOS affects the development of GDM, GHTN and PEC. This is most likely due to the complex, multifactorial etiology of PCOS, its range of potential confounders for pregnancy complications and the variable methodology of studies that have been conducted. To date, the largest meta-analysis on this subject includes 11 565 women with PCOS analyzed for their risk of GDM and 5896 patients analyzed for their risk of PEC.

STUDY DESIGN, SIZE, DURATION

This is a retrospective population-based study utilizing data from the HCUP-NIS over 11 years from 2004 to 2014. A dataset of all deliveries between 2004 and 2014 inclusively was created. Within this group, all deliveries to women with PCOS were identified as part of the study group (n = 14 882), and the remaining deliveries were categorized as non-PCOS births and comprised the reference group (n = 9 081 906).

PARTICIPANTS/MATERIALS, SETTING, METHODS

The HCUP-NIS is the largest inpatient sample database in the USA and is comprised of hospital inpatient stays submitted by hospitals throughout the entire country. Each year, the database provides information relating to 7 million inpatient stays, including patient characteristics, diagnosis and procedures. The data are representative of ∼20% of admissions to US hospitals across 48 states and the District of Columbia.

MAIN RESULTS AND THE ROLE OF CHANCE

At baseline, more pregnant women with PCOS were obese (22.3% vs. 3.5%, P < 0.001), had chronic hypertension (HTN) (8.4% vs. 1.8%, P < 0.001), had pregestational diabetes (4.1% vs. 0.9%, P < 0.001) and had treated thyroid disease (12.6% vs. 2.4%, P < 0.001). Women with PCOS were also more likely to have undergone IVF treatment (2.4% vs. 0.1%, P < 0.001), have multi-gestation pregnancies (5.9% vs. 1.5%, P < 0.001), and more multiple gestations (MGs) in the PCOS group were the result of IVF treatment than the non-PCOS groups (12.3% vs. 2.3%, P < 0.001). In all pregnancies, women with PCOS were more likely to develop gestational diabetes (adjusted odds ratio (aOR) 2.19, 95% CI 2.02-2.37), pregnancy associated HTN (aOR 1.38, 95% CI 1.27-1.50, P < 0.001), GHTN (aOR 1.47, 95% CI 1.31-1.64), PEC (aOR 1.29, 95% CI 1.14-1.45) and superimposed PEC (aOR 1.29, 95% CI 1.04-1.59) after controlling for confounding effects (age, race, income level, insurance type, obesity, IVF use, previous cesarean section, chronic HTN, pregestational diabetes, thyroid disease, MG, smoking and recreational drug use). Odds ratios were comparable between all pregnancies and singleton pregnancies only. In women pregnant with multiple fetuses, PCOS only conferred a statistically significant increased risk of developing GDM (aOR 2.33, 95% CI 1.92-2.83, P < 0.001). However, there was a trend toward an increased risk for developing pregnancy associated HTN (aOR 1.92, 95% CI 0.99-1.42, P = 0.058).

LIMITATIONS, REASONS FOR CAUTION

This is a retrospective analysis utilizing an administrative database which relies on the accuracy and consistency of the individuals coding the data. There are known limitations in how accurately hospital coding is able to capture perinatal conditions and complications, making it difficult to know with certainty that such events are accurate.

WIDER IMPLICATIONS OF THE FINDINGS

Pregnant women with PCOS are at increased risk of adverse complications in pregnancy even when they do not present with other coexisting metabolic conditions. Furthermore, it is important to also consider the risk of all other coexisting metabolic conditions frequently encountered in PCOS women, as these risks are additive and place women with PCOS at significantly increased risk for adverse complications in pregnancy.

STUDY FUNDING/COMPETING INTEREST(S)

None.

Associations between polycystic ovary syndrome and adverse obstetric and neonatal outcomes: a population study of 9.1 million births

STUDY QUESTION

Does polycystic ovary syndrome (PCOS) confer an independent risk for adverse delivery and neonatal outcomes, based on analysis of the Healthcare Cost and Utilization Project-Nationwide Inpatient Sample (HCUP-NIS) database?

SUMMARY ANSWER

After controlling for all potential confounding effects, women with PCOS are at an increased risk of experiencing preterm pre-labour rupture of membranes (PPROM), pre-term delivery (PTD), placental abruption, caesarean section (C/S) delivery, chorioamnionitis and post-partum maternal infections.

WHAT IS KNOWN ALREADY

PCOS may be associated with an increased risk of adverse perinatal outcomes. However, there remain significant gaps in understanding the correlation between PCOS and important delivery and neonatal complications.

STUDY DESIGN, SIZE, DURATION

This is a retrospective population-based cohort study utilising data from the HCUP-NIS over 11 years from 2004 to 2014. A cohort of all deliveries between 2004 and 2014 inclusively was created. Within this group, all deliveries to women with PCOS were identified as part of the study group (n = 14 882), and the remaining deliveries were categorised as non-PCOS births and comprised the reference group (n = 9 081 906).

PARTICIPANTS/MATERIALS, SETTING, METHODS

The HCUP-NIS is the largest inpatient sample database in the USA and it is comprised of hospital inpatient stays throughout the entire country. It provides information relating to 7 million inpatient stays per year, includes ∼20% of admissions, and represents over 96% of the American population.

MAIN RESULTS AND THE ROLE OF CHANCE

After adjustment for all potential confounders, women with PCOS were more likely to experience PPROM (aOR 1.48, 95% CI 1.20-1.83), PTD (aOR 1.37 95% CI 1.24-1.53) and placental abruption (aOR 1.63, 95% CI 1.30-2.05) and were more likely to deliver by C/S (aOR 1.50, 95% CI 1.40-1.61 (all P < 0.001). Women with PCOS more often developed chorioamnionitis (aOR 1.58, 95% CI 1.34-1.86, P < 0.001) and maternal infections (aOR 1.58, 95% CI 1.36-1.84 (both P < 0.001)). With the exception of multiple gestations (aOR 1.27, 95% CI 1.01-1.62, P = 0.04), there was no difference in the number of women who gave birth to small for gestational age (SGA) infants (aOR 0.97, 95% CI 0.82-1.15, P = 0.72) between the women with PCOS and the reference group. Intrauterine foetal deaths (IUFDs) were also comparable between the two groups (aOR 1.03, 95% CI 0.68-1.59, P = 0.88). However, congenital anomalies were more likely to occur in the offspring of women with PCOS (aOR 1.89, 95% CI 1.51-2.38, P < 0.001).

LIMITATIONS, REASONS FOR CAUTION

This is a retrospective analysis utilising an administrative database which relies on the accuracy and consistency of the individuals coding the data. There are known limitations in how accurately hospital coding is able to capture perinatal conditions and complications, making it difficult to know with certainty that such events are accurate.

WIDER IMPLICATIONS OF THE FINDINGS

Women with PCOS are more likely to experience adverse delivery and neonatal outcomes. It is important to additionally consider the risk of all other co-existing conditions frequently encountered in PCOS women, as these risks are additive and place women with PCOS at significantly increased risk of adverse pregnancy outcomes.

STUDY FUNDING/COMPETING INTEREST(S)

No specific funding was obtained for this study. The authors have no conflicts of interest to disclose.

The implications of vitamin content in the plasma in reference to the parameters of carbohydrate metabolism and hormone and lipid profiles in PCOS

So far, there have been no analyses of correlations between the level of water-soluble vitamins in women with polycystic ovary syndrome (PCOS) and hormone and lipid profiles as well as carbohydrate metabolism. The unpopular concept that PCOS may also be conditioned by a chronic infection leads to a suspicion that water-soluble vitamins may be involved in the struggle against PCOS. This is why the aim of this research was to determine whether there are any indications that could confirm this hypothesis. The study included 64 women of Caucasian race: 50 patients aged 29.52 ± 7.01 years with PCOS, diagnosed according to the Rotterdam criteria. The control group consisted of 14 women aged 30.23 ± 6.3 years with correct BMI. HPLC Infinity1260 Binary LC (Agilent Technologies, Waldbronn, Germany) was used to analyze nine vitamins. The vitamins were separated using the gradient method, a buffer of 25 mM HK2PO4 with pH equal to 7.0, and 100 % methanol buffer. The acquired results were compared using Statistica 12.0 (Statsoft, Tulsa, Oklahoma, USA). Non-parametric tests were used: Mann-Whitney tests for comparisons between groups (PCOS and control group, CG), in which p < 0.05 was considered statistically significant. Subsequently, we performed a correlation matrix of the biochemical parameters of blood with vitamins at p ≤ 0.05. Higher concentrations of ascorbic acid were observed in PCOS. The content of the remaining vitamins was higher in the control group, and the statistical differences were significant in reference to thiamine, riboflavin, pyridoxine and folic acid in comparison to the control group. A significant positive correlation was observed between vitamin C and testosterone/insulin, another between riboflavin and androstenedione/testosterone, next between biotin and thyrotropic hormone (TSH), between pantothenic acid and dehydroepiandrosteron (DHEA-SO4), and finally between pyridoxine and androstenedione. A negative correlation was observed in the case of niacin with sex hormone binding protein (SHBG) and high density lipoprotein (HDL). Water-soluble vitamins play an important role in the therapy of women with PCOS through the reduction of antioxidative stress and low-intensity inflammation caused by various factors, including chronic infection.

Fundamental Concepts and Novel Aspects of Polycystic Ovarian Syndrome: Expert Consensus Resolutions

Polycystic ovary syndrome (PCOS) is a very common endocrine and metabolic disorder with the involvement of both genetic and environmental factors. Although much has been clarified on its pathogenesis, diagnosis, clinical manifestations, and therapy, there are still areas of uncertainty. To address fundamental concepts, novel aspects and hypotheses, and future perspectives, including the possible additional benefits of treatment with nutraceuticals, an expert consensus panel formed by endocrinologists and gynecologists was established. After an independent review of the literature, the panel convened electronically on February 3, 2020, and six resolutions were created, debated, and agreed upon discussion, and finally approved in their final form in a consensus livestream meeting held on April 15. The summary of the resolutions are: (1) PCOS is a well-established medical condition that negatively affects reproduction, general health, sexual health, and quality of life; (2) the symptoms and signs of PCOS appear early in life especially in female newborns from PCOS carriers; (3) women with PCOS have significantly increased risk of pregnancy-related complications including gestational diabetes mellitus; (4) a male PCOS equivalent exists, and it may impact on metabolic health and probably on reproduction; (5) the evidence supports that medical therapy for PCOS is effective, rational, and evidence-based; (6) the evidence supports a major research initiative to explore possible benefits of nutraceutical therapy for PCOS. The proposed resolutions may be regarded as points of agreement based on the current scientific evidence available.

Polycystic Ovary Syndrome and NC-CAH: Distinct Characteristics and Common Findings. A Systematic Review

Background: Twenty-one-hydroxylase-deficient non-classic adrenal hyperplasia (NC-CAH) is a very common autosomal recessive syndrome with prevalence between 1:1,000 and 1:2,000 individuals and the frequency varies according to ethnicity. On the other hand, polycystic ovary syndrome has a familial basis and it is inherited under a complex hereditary trait. This syndrome affects 6 to 10% of women in reproductive age and it is the most common endocrine disorder in young women. Our aim was to investigate, through a systematic review, the distinct characteristics and common findings of these syndromes. Methods: The search period covered January 1970 to November 2018, using the scientific databases PubMed. Inclusion criteria were adult women patients with PCOS or NC-CAH. Search terms were "polycystic ovary syndrome," "PCOS," "non-classical adrenal hyperplasia," "NC-CAH," "21-hydroxylase deficiency." From an initial 16,255 titles, the evaluations led to the final inclusion of 97 papers. Results: The clinical features of NC-CAH are hirsutism and ovulatory and menstrual dysfunction therefore; differentiation between these two syndromes is difficult based on clinical grounds only. Additionally, NC-CAH and PCOS are both associated with obesity, insulin resistance, and dyslipidaemia. Reproductive abnormalities are also common between these hyperandrogenemic disorders since in patients with NC-CAH polycystic ovarian morphology and subfertility are present as they are in women with PCOS. The diagnosis of PCOS, is confirmed once other disorders that mimic PCOS have been excluded e.g., conditions that are related to oligoovulation or anovulation and/or hyperandrogenism, such as hyperprolactinaemia, thyroid disorders, non-classic congenital adrenal hyperplasia, and androgen-producing neoplasms. Conclusions: The screening tool to distinguish non-classic adrenal hyperplasia from PCOS is the measurement of 17-hydroxyprogesterone levels. The basal levels of 17-hydroxyprogesterone may overlap, but ACTH stimulation testing can distinguish the two entities. In this review these two common endocrine disorders are discussed in an effort to unveil their commonalities and to illuminate their shadowed distinctive characteristics.