Low birth weight may increase body fat mass in adult women with polycystic ovarian syndrome

Immune Dysfunction in Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in reproductive-aged individuals with ovaries. It is associated with anovulation and increased risk to fertility and metabolic, cardiovascular, and psychological health. The pathophysiology of PCOS is still inadequately understood, although there is evidence of persistent low-grade inflammation, which correlates with associated visceral obesity. Elevated proinflammatory cytokine markers and altered immune cells have been reported in PCOS and raise the possibility that immune factors contribute to ovulatory dysfunction. Because normal ovulation is modulated by immune cells and cytokines in the ovarian microenvironment, the endocrine and metabolic abnormalities associated with PCOS orchestrate the accompanying adverse effects on ovulation and implantation. This review evaluates the current literature on the relationship between PCOS and immune abnormalities, with a focus on emerging research in the field.

Exposure to Famine During Early Life and Abdominal Obesity in Adulthood: Findings from the Great Chinese Famine During 1959⁻1961

Undernutrition during early life may lead to obesity in adulthood. This study was conducted to examine the relationship between famine exposure during early life and the risk of abdominal obesity in adulthood. A total of 18,984 and 16,594 adults were surveyed in 2002 and 2010-2012 in two nationally representative cross-sectional surveys, namely China Nutrition and Health Survey, respectively. The risk of abdominal obesity was evaluated for participants born during 1956-1961 and compared with that of participants born during 1962-1964. The overall prevalence of abdominal obesity in adulthood showed a positive association with famine exposure during early life. The odds ratios of famine exposure were 1.31 (1.19-1.44) and 1.28 (1.17-1.40) in 2002 during fetal life and infancy and 1.09 (1.00-1.19) in 2012 during fetal life, respectively. The relationships between famine exposure and abdominal obesity across the famine exposure groups were distinct among females and those who lived in urban areas and were physical inactive (p < 0.05). Exposure to famine during early life was associated with increased risks of abdominal obesity in adulthood, which was partially alleviated by healthy lifestyle factors (e.g., physical activity).

Birthweight and PCOS: systematic review and meta-analysis

STUDY QUESTION

Are intrauterine conditions, reflected in birthweight, associated with the development of polycystic ovary syndrome (PCOS)?

SUMMARY ANSWER

Our study indicates that a low birthweight as a summary measure of intrauterine environment may be associated with PCOS when diagnosed according to the Rotterdam criteria.

WHAT IS ALREADY KNOWN

The etiology of PCOS is still largely unknown. Besides subfertility, women diagnosed with PCOS have an increased risk of chronic health issues. PCOS has been linked to adverse prenatal conditions, including a low birthweight.

STUDY DESIGN SIZE DURATION

A systematic search of the literature and meta-analysis of pooled data was undertaken, according to the preferred reporting items for systematic reviews and meta-analysis (PRISMA) and meta-analysis of observational studies in epidemiology (MOOSE) guidelines.

PARTICIPANTS/MATERIALS SETTING METHOD

The following online databases were systematically searched: PubMed, EMBASE, CINAHL (via EBSCO) and Cochrane library up to 10 June 2017, with no language or date restrictions.

MAIN RESULTS AND THE ROLE OF CHANCE

A total of 1484 studies were identified of which 16 met the inclusion criteria and 14 provided data for meta-analysis. The exposure variable birthweight was either analyzed as a categorical variable using the birthweight categories <2.5, 2.5-4 and >4 kg, or as a continuous variable. We composed a birthweight category consisting of birthweights <2.5 kg plus birthweights >4 kg, reflecting extreme birthweights. In a subset analysis, we investigated the association between a low birthweight and PCOS while differentiating between Rotterdam and NIH criteria. When diagnosed according to the Rotterdam criteria, women born with birthweights lower than 2.5 kg had an odds ratio [95% CI] of 1.76 [1.14,2.70] for PCOS compared to women born with birthweights higher than 2.5 kg. For the latter analysis, we were able include 1252 women (I ² = 16%). There was no significant effect of birthweight on PCOS when diagnosed according to NIH criteria.

LIMITATIONS REASONS FOR CAUTION

The funnel plot of the studies providing data for the meta-analysis and the subset analysis indicates a publication bias.

WIDER IMPLICATIONS OF THE FINDINGS

A low birthweight could be a risk factor for PCOS when diagnosed according to the Rotterdam criteria.

STUDY FUNDING/COMPETING INTERESTS

None.

TRIAL REGISTRATION NUMBER

The protocol of this study was registered at PROSPERO under registration number CRD42016048972.

Exposure to famine in early life and the risk of obesity in adulthood in Qingdao: Evidence from the 1959-1961 Chinese famine

BACKGROUND AND AIMS

We aimed to evaluate the association between famine exposure during early life and obesity and obesity_max (obese at the highest weight) in adulthood.

METHODS AND RESULTS

Data were from two population-based cross-sectional surveys conducted in 2006 and 2009 in Qingdao, China. A total of 8185 subjects born between 1/1/1941 and 12/31/1971 were categorized into unexposed (born between 01/01/1962 and 12/31/1971), fetal/infant exposed (born between 01/01/1959 and 12/31/1961), childhood exposed (born between 01/01/1949 and 12/31/1958) and adolescence exposed (born between 01/01/1941 and 12/31/1948) according to their age when exposed to the Chinese famine from 1959 to 1961. Obesity was defined as BMI (body mass index) ≥28.0 and obesity_max was defined as BMI_max (BMI at the highest weight) ≥28.0. We compared fetal/infant exposed, childhood exposed and adolescence exposed to the unexposed using logistic regression models to assess the effect of famine exposure on later obesity and obesity_max. Fetal/infant exposed (OR = 1.59, P < 0.001), childhood exposed (OR = 1.42, P < 0.01) and adolescence exposed (OR = 1.86, P < 0.01) all had higher risks of obesity than the unexposed. Exposure groups were more likely to be obese at their highest weight than the unexposed, and ORs (95%CIs) for obesity_max in the fetal/infant exposed, childhood exposed and adolescence exposed were 1.49(1.20-1.86), 1.24(1.02-1.49) and 1.64 (1.40-1.93), respectively. Similar results were found in both men and women.

CONCLUSION

Exposure to famine in early life was associated with increased risks of obesity and obesity_max in adulthood. Preventing undernutrition in early life appears beneficial to reduce the prevalence of later obesity.