Maternal metabolic conditions as predictors of breastfeeding outcomes: Insights from an Australian cohort study.

INTRODUCTION: Breastfeeding represents an important opportunity to optimize health outcomes for both mother and infant, particularly in the context of maternal metabolic conditions such as diabetes and polycystic ovary syndrome. However, evidence suggests that women affected by these conditions breastfeed at reduced rates and durations. Our aim was to use the large, prospective, community-based Australian Longitudinal Study on Women's Health (ALSWH) to conduct an in-depth exploratory analysis of breastfeeding outcomes in Australian women affected by key maternal metabolic conditions. MATERIAL AND METHODS: Data from 12 920 pregnancies to 5605 women from the 1973-1978 birth cohort of the ALSWH were examined. Univariable and multivariable regression using generalized estimating equation models were applied to assess breastfeeding initiation and duration (outcome measures) in relation to key self-reported maternal metabolic diagnoses (pre-gestational type 1 and type 2 diabetes, gestational diabetes, and polycystic ovary syndrome; main explanatory variables). Key sociodemographic and clinical covariates were also considered. RESULTS: Results showed no significant association between specific maternal metabolic diagnoses (pre-gestational or gestational diabetes, or polycystic ovary syndrome) and breastfeeding outcomes. However, maternal body mass index emerged as a key predictor of suboptimal breastfeeding outcomes. Pregnancies affected by maternal obesity were associated with a 2.1-fold increase in the odds of not initiating breastfeeding, after adjusting for other key variables (95% CI 1.67 to 2.60, p < 0.01). Maternal overweight and obesity were, respectively, associated with an adjusted 1.4-fold (95% CI 1.20 to 1.55, p < 0.01) and 1.8-fold increase (95% CI 1.60 to 2.10, p < 0.01) in the odds of a breastfeeding duration less than 6 months. CONCLUSIONS: Maternal obesity, rather than any specific maternal metabolic condition, appears to be a key predictor of breastfeeding outcomes in Australian women.

Prolactin in Pregnancies Affected by Pre-Existing Maternal Metabolic Conditions: A Systematic Review.

Women affected by maternal pregestational diabetes mellitus (type 1 or type 2) or by polycystic ovary syndrome experience an increased risk of pregnancy complications, as well as suboptimal lactation outcomes. The hormone prolactin plays important roles in pregnancy and postpartum, both as a metabolic and lactogenic hormone. We aimed to explore, through a systematic review, the relationship between pregestational maternal metabolic conditions and prolactin levels in pregnancy and postpartum. MEDLINE via OVID, CINAHL Plus, and Embase were searched from inception to 9 May 2022. Eligible studies included women who were pregnant or up to 12 months postpartum and had a pre-existing diagnosis of type 1 or type 2 diabetes mellitus or polycystic ovary syndrome; with reporting of at least one endogenous maternal serum prolactin level during this time. Two independent reviewers extracted the data. Eleven studies met the eligibility criteria. The studies were too diverse and heterogeneous to enable meta-analysis. Overall, prolactin levels appeared to be lower in pregnancies affected by type 1 diabetes mellitus. There was little data in polycystic ovary syndrome or type 2 diabetes pregnancy, but prolactin increment across pregnancy in polycystic ovary syndrome emerged as an area for future study. During postpartum, lactation difficulties in women with metabolic disease present before pregnancy are well-described, but the relationship to prolactin remains unclear. Overall, preliminary evidence suggests that pre-existing maternal metabolic disease may alter prolactin dynamics in pregnancy and postpartum. Further well-designed studies in modern cohorts, with standardised collection and serial sampling across pregnancy and postpartum, are required to clarify these associations.

Human Placental Lactogen in Relation to Maternal Metabolic Health and Fetal Outcomes: A Systematic Review and Meta-Analysis.

Human placental lactogen (hPL) is a placental hormone which appears to have key metabolic functions in pregnancy. Preclinical studies have putatively linked hPL to maternal and fetal outcomes, yet-despite human observational data spanning several decades-evidence on the role and importance of this hormone remains disparate and conflicting. We aimed to explore (via systematic review and meta-analysis) the relationship between hPL levels, maternal pre-existing and gestational metabolic conditions, and fetal growth. MEDLINE via OVID, CINAHL plus, and Embase were searched from inception through 9 May 2022. Eligible studies included women who were pregnant or up to 12 months post-partum, and reported at least one endogenous maternal serum hPL level during pregnancy in relation to pre-specified metabolic outcomes. Two independent reviewers extracted data. Meta-analysis was conducted where possible; for other outcomes narrative synthesis was performed. 35 studies met eligibility criteria. No relationship was noted between hPL and gestational diabetes status. In type 1 diabetes mellitus, hPL levels appeared lower in early pregnancy (possibly reflecting delayed placental development) and higher in late pregnancy (possibly reflecting increased placental mass). Limited data were found in other pre-existing metabolic conditions. Levels of hPL appear to be positively related to placental mass and infant birthweight in pregnancies affected by maternal diabetes. The relationship between hPL, a purported pregnancy metabolic hormone, and maternal metabolism in human pregnancy is complex and remains unclear. This antenatal biomarker may offer value, but future studies in well-defined contemporary populations are required.

Where are we in understanding the natural history of polycystic ovary syndrome? A systematic review of longitudinal cohort studies.

STUDY QUESTION: What is the natural history of reproductive, psychological and oncological features in women with polycystic ovary syndrome (PCOS) in comparison to those without PCOS across the life course? SUMMARY ANSWER: Existing longitudinal data on changes in reproductive, psychological and oncological features in PCOS are inadequate and conflicting, but the limited evidence suggests that total testosterone (T) and dehydroepiandrosterone sulphate (DHEAS) levels decline more significantly in women with PCOS than in those without PCOS, and the risk of gestational diabetes is higher in pregnant women with PCOS compared to their counterparts without PCOS. WHAT IS KNOWN ALREADY: The progression of reproductive, psychological and oncological features in PCOS remains unclear, which limits prevention and early diagnosis strategies across the lifespan. Understanding the natural history of PCOS is one of the overarching priorities in PCOS research. STUDY DESIGN, SIZE, DURATION: This is a systematic review of longitudinal cohort studies with a narrative presentation of findings. Databases MEDLINE, EMBASE, Ovid PsycInfo, CINAHL PLUS and EBM reviews were searched between 15 January 2020 and 11 February 2021 with no language restrictions. Only studies published from the year 1990 to February 2021 were included. PARTICIPANTS/MATERIALS, SETTING, METHODS: In line with current guidelines for the assessment and management of PCOS, we included studies where participants were females with PCOS diagnosed according to the 2003 Rotterdam or the 1990 National Institutes of Health (NIH) consensus criteria. MAIN RESULTS AND THE ROLE OF CHANCE: A total of 21 longitudinal studies including 62 123 participants over four continents reported reproductive, psychological and/or oncological outcomes. Participants were females aged between 15 and 49 years at baseline, with follow-up periods ranging from 4 weeks to 32 years. Consistent evidence based on limited studies suggests that total T and DHEAS levels decline to a greater degree in women with PCOS compared to those without PCOS, and the risk gestational diabetes is higher in women with PCOS than in those without PCOS. Evidence reporting changes over time in the majority of the remaining outcomes was unclear due to conflicting and/or insufficient information. LIMITATIONS, REASONS FOR CAUTION: There was extreme heterogeneity between studies in terms of study setting, population characteristics, follow-up period, effect measures used and laboratory testing approaches. WIDER IMPLICATIONS OF THE FINDINGS: Understanding the natural history of PCOS and changes in diagnostic, reproductive, psychological and oncological features of PCOS across the lifespan is still a challenge and the existing literature is both limited and conflicting. It is important that future long-term prospective longitudinal studies are conducted in unselected and well-characterized populations. STUDY FUNDING/COMPETING INTEREST(S): This specific study was not funded. S.K. is supported by scholarships from the Research Training Program of the Commonwealth of Australia and Monash University; H.J.T. is supported by an Australian National Health and Medical Research Council fellowship; and A.E.J. is supported by the Australian National Health and Medical Research Council's Centre for Research Excellence in Women's Health in Reproductive Life. R.A. was employed by the American Society for Reproductive Medicine and is a consultant to Spruce Biosciences and Fortress Biotech. The other authors have no conflicts of interest to declare. REGISTRATION NUMBER: Prospero registration number: CRD42020165546.

Lactogenic hormones in relation to maternal metabolic health in pregnancy and postpartum: protocol for a systematic review.

INTRODUCTION: Maternal metabolic disease states (such as gestational and pregestational diabetes and maternal obesity) are reaching epidemic proportions worldwide and are associated with adverse maternal and fetal outcomes. Despite this, their aetiology remains incompletely understood. Lactogenic hormones, namely, human placental lactogen (hPL) and prolactin (PRL), play often overlooked roles in maternal metabolism and glucose homeostasis during pregnancy and (in the case of PRL) postpartum, and have clinical potential from a diagnostic and therapeutic perspective. This paper presents a protocol for a systematic review which will synthesise the available scientific evidence linking these two hormones to maternal and fetal metabolic conditions/outcomes. METHODS AND ANALYSIS: MEDLINE (via OVID), CINAHL and Embase will be systematically searched for all original observational and interventional research articles, published prior to 8 July 2021, linking hPL and/or PRL levels (in pregnancy and/or up to 12 months postpartum) to key maternal metabolic conditions/outcomes (including pre-existing and gestational diabetes, markers of glucose/insulin metabolism, postpartum glucose status, weight change, obesity and polycystic ovary syndrome). Relevant fetal outcomes (birth weight and placental mass, macrosomia and growth restriction) will also be included. Two reviewers will assess articles for eligibility according to prespecified selection criteria, followed by full-text review, quality appraisal and data extraction. Where possible, meta-analysis will be performed; otherwise, a narrative synthesis of findings will be presented. ETHICS AND DISSEMINATION: Formal ethical approval is not required as no primary data will be collected. The results will be published in a peer-reviewed journal and presented at conference meetings, and will be used to inform future research directions. PROSPERO REGISTRATION NUMBER: CRD42021262771.

Prolactin in relation to gestational diabetes and metabolic risk in pregnancy and postpartum: A systematic review and meta-analysis.

Context: Pre-clinical evidence suggests that prolactin has important metabolic functions in pregnancy and postpartum, in addition to lactogenic actions. Objective: To explore the relationship between prolactin and maternal metabolic outcomes in human pregnancy and postpartum, particularly in relation to gestational diabetes mellitus (GDM). Data sources: MEDLINE via OVID, CINAHL plus, Embase. Study selection: Eligible studies included women who were pregnant or up to 12 months postpartum, reporting at least one maternal serum prolactin level in relation to key metabolic outcomes including GDM, glycaemic parameters, obesity, and gestational weight gain. Data extraction: Two independent reviewers extracted data. Data synthesis: Twenty-six articles were included. Meta-analysis showed no relationship between maternal prolactin levels and GDM status, with a weighted mean difference of -2.14 ng/mL (95% CI -12.54 to 8.27 ng/mL, p=0.7) between GDM and controls in early pregnancy (n=3 studies) and -3.89 ng/mL (95% CI, -15.20 to 7.41 ng/mL, p=0.5) in late pregnancy (n=11 studies). In narrative synthesis of other outcomes (due to study heterogeneity and/or lack of data), prolactin levels were not associated with maternal glycaemic or weight-related parameters during pregnancy, but in the postpartum period (particularly with lactation) a high-prolactin environment was associated with low circulating insulin and beta-cell function, and increased insulin sensitivity. Conclusions: Current evidence from human studies does not clearly support a relationship between prolactin and metabolic parameters during pregnancy, including with GDM status. Elevated prolactin was associated with lower insulin and beta-cell function and higher insulin sensitivity in the post-partum period, but the direction of causality remains unclear. Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier [CRD42021262771].

Natural history of polycystic ovary syndrome: A systematic review of cardiometabolic outcomes from longitudinal cohort studies.

OBJECTIVE: Women with polycystic ovary syndrome (PCOS) have a worsened metabolic profile but the progression of cardiometabolic features over time is unclear. Understanding this natural history is a key priority in PCOS research and vital for guiding the prevention and management of this common condition. We explored cardiometabolic changes that are observed in women with PCOS compared to those without PCOS across the life course. DESIGN, PATIENTS AND MEASUREMENTS: A systematic review of longitudinal cohort studies was conducted across MEDLINE, EMBASE, Ovid PsycInfo, CINAHL PLUS and EBM reviews between 15 January 2020 and 11 February 2021. Eligible studies included participants with or without PCOS diagnosed according to the 2003 Rotterdam or the 1990 National Institutes of Health (NIH) criteria. We included studies that were published from the year 1990 to 2021 with data on cardiometabolic outcomes as per the PCOS core outcomes set. RESULTS: There were 31 longitudinal studies with 28,316 participants from four continents. At the start of follow up, participants were aged between 1 year and 49 years with a follow-up period ranging from 2 to 32 years. Changes in BMI and the risk of coronary heart disease were similar in adult women with and without PCOS. Women with PCOS had a higher risk of Type 2 diabetes than their non-PCOS counterparts. Evidence for the majority of all other outcomes was conflicting and with inadequate data. CONCLUSION: Understanding the natural history of PCOS and particularly changes in cardiometabolic features remains challenging. Existing literature is extensive but heterogeneous and inconsistent. Longitudinal studies in unselected populations are needed to provide high-quality data in this area.

Metabolic Conditions Including Obesity, Diabetes, and Polycystic Ovary Syndrome: Implications for Breastfeeding and Breastmilk Composition.

Breastfeeding is internationally recognized as the recommended standard for infant nutrition, informed by evidence of its multiple benefits for both mother and baby. In the context of common metabolic conditions such as polycystic ovary syndrome, diabetes (type 1, type 2, and gestational), and obesity, breastfeeding may be particularly beneficial for both mother and infant. However, there is evidence of delayed lactogenesis and reduced breastfeeding rates and duration in women with these conditions, and the effects of altered maternal metabolic environments on breastmilk composition (and potentially infant outcomes) are incompletely understood. In this review, we explore the relationships between maternal metabolic conditions, lactogenesis, breastfeeding, and breastmilk composition. We examine relevant potential mechanisms, including the central role of insulin both in lactogenesis and as a milk-borne hormone. We also describe the bioactive and hormonal components of breastmilk and how these may link maternal and infant health.

Metabolomic Biomarkers in Gestational Diabetes Mellitus: A Review of the Evidence.

Gestational diabetes mellitus (GDM) is the fastest growing type of diabetes, affecting between 2 to 38% of pregnancies worldwide, varying considerably depending on diagnostic criteria used and sample population studied. Adverse obstetric outcomes include an increased risk of macrosomia, and higher rates of stillbirth, instrumental delivery, and birth trauma. Metabolomics, which is a platform used to analyse and characterise a large number of metabolites, is increasingly used to explore the pathophysiology of cardiometabolic conditions such as GDM. This review aims to summarise metabolomics studies in GDM (from inception to January 2021) in order to highlight prospective biomarkers for diagnosis, and to better understand the dysfunctional metabolic pathways underlying the condition. We found that the most commonly deranged pathways in GDM include amino acids (glutathione, alanine, valine, and serine), carbohydrates (2-hydroxybutyrate and 1,5-anhydroglucitol), and lipids (phosphatidylcholines and lysophosphatidylcholines). We also highlight the possibility of using certain metabolites as predictive markers for developing GDM, with the use of highly stratified modelling techniques. Limitations for metabolomic research are evaluated, and future directions for the field are suggested to aid in the integration of these findings into clinical practice.

A case of hyperprolactinaemia in a patient with metastatic melanoma.

Ectopic prolactin production from a malignancy is infrequently reported. We report here a 60-year-old gentleman who presented with hyperprolactinaemia (9100 mIU/L) causing expressible galactorrhoea, decreased libido and fatigue thought to be due to ectopic prolactin secretion from a metastatic melanoma. Upon initiation of pembrolizumab, the patient's symptoms resolved and he became normoprolactinaemic. This corresponded with a partial response on radiological imaging. Although the core biopsy of the metastatic melanoma did not exhibit immunostaining for prolactin, we believe that only a subset of the tumour cells possesses prolactin-secreting capacity. This case illustrates the need to consider ectopic prolactin production for a solid malignant tumour as a rare cause of hyperprolactinaemia in patients with a normal pituitary MRI, in the absence of other causes.

Bisphosphonate Use and Fractures in Adults with Hypophosphatasia.

Adults with hypophosphatasia (HPP) may suffer femoral fractures resembling the atypical femoral fractures that can occur with long-term bisphosphonate treatment, and there is an emerging consensus that bisphosphonates should not be used in adults with HPP and low bone mass. However, the spectrum of HPP in adults is wide: ranging from the severely affected-who commonly have osteomalacia-through to the minimally affected. The former typically have biallelic and the latter, heterozygous ALPL mutations. We have reviewed reports of fractures in adults with genetically proven HPP which suggest that the risk of fracture is at least 200-fold greater in those with biallelic mutations. We also discuss two cases of postmenopausal women with heterozygous ALPL mutations. One had fractures and severe osteoporosis, but histology revealed no evidence of osteomalacia. The second had taken alendronate for 8 years, but despite profound suppression of bone turnover, histology again revealed no evidence of osteomalacia. The management of adults with HPP who have coexisting osteoporosis is challenging. More data are clearly needed, but we suggest that the risks of bisphosphonate therapy may be relatively low in patients who have heterozygous mutations and no histological evidence of osteomalacia. © 2019 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research © 2019 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research.

The apprenticeship model of clinical medical education: time for structural change.

The apprenticeship model, which forms the backbone of the current medical education system, has a strong historical precedent (and indeed multiple strengths). It is, however, important to acknowledge that its application to modern medicine is far from perfect, particularly with the breadth and complexity of current hospital systems. Demands on clinician resources, the sheer volume of knowledge our trainees must amass, short attachments and rigorous assessment schedules are all major challenges to a relatively simplistic educational system. Identifying and addressing these vulnerabilities is essential to enhancing the educational experiences of both undergraduate medical students and junior doctors.