Effectiveness of Non-Pharmacological Interventions for Overweight or Obese Infertile Women: A Systematic Review and Meta-Analysis

Obesity and female infertility

Infertility is a significant global health issue, with a negative impact on people's wellbeing and human rights. Despite the longstanding association between obesity and infertility, there remains uncertainty, about the precise mechanisms underpinning this association and best management strategies. In this article, we aimed to address these uncertainties by reviewing the recent literature, and focusing on studies which evaluated live birth rates. We found that just over half of the studies, investigating the relationship between preconception maternal weight and live birth rates found an inverse correlation. There was, however, insufficient evidence, that preconception maternal lifestyle or pharmacological interventions in obese women with infertility, resulted in improved live birth rates. The implications for clinical practice and future research are highlighted. For example, the need to consider some flexibility in applying strict preconception body mass index targets, limiting access to fertility treatment, and a need for large clinical trials of new pharmacological options and bariatric surgery.

Addressing Obesity in Preconception, Pregnancy, and Postpartum: A Review of the Literature

PURPOSE OF REVIEW

Reproductive-aged women (aged 19 to 50 years) are a key population warranting focused research for the prevention of overweight and obesity. This review highlights the importance of addressing weight before, during and after pregnancy.

RECENT FINDINGS

Obesity decreases fertility during the preconception period; increases the risk of adverse pregnancy outcomes including gestational diabetes, pre-eclampsia and caesarean section and postpartum weight retention; and increases the long-term health risks for both the mother and offspring. Despite overwhelming efficacy evidence on solutions, there are significant implementation gaps in translating this evidence into pragmatic models of care and real-world solutions. Interventions during preconception, pregnancy and postpartum are likely to be cost-effective or cost-saving, with future investigation needed in the preconception and postpartum period. International clinical guidelines and public health policies are needed for a concerted effort to prevent unhealthy weight gain in these life stages and to reverse the significant adverse health outcomes for women and the next generation.

Effects of nutrition on metabolic and endocrine outcomes in women with polycystic ovary syndrome: an umbrella review of meta-analyses of randomized controlled trials

CONTEXT

Numerous meta-analyses have been conducted on the effects of nutritional interventions on various health outcomes in women with polycystic ovary syndrome (PCOS). However, the strength of the evidence and its clinical significance are unclear.

OBJECTIVE

This umbrella review aimed to summarize the effects of nutritional interventions on women with PCOS and assess the strength of the evidence.

DATA SOURCES

PubMed, Scopus, and Web of Science were searched from inception until March 17, 2021.

DATA EXTRACTION

Meta-analyses of randomized clinical trials (RCTs) that examined the impact of dietary modifications or supplementations on women with PCOS were selected. Data extraction, quality assessments of the meta-analyses, and evaluation of the strength of the evidence were conducted independently by 2 investigators and confirmed by a third.

DATA ANALYSIS

Twenty-eight RCT meta-analyses were included, reporting 40 different outcomes. Lower carbohydrate, Dietary Approaches to Stop Hypertension, or lower glycemic index/load diets in women with PCOS significantly improved some anthropometric and metabolic characteristics (with very low to low certainty). Probiotics/synbiotics reduced fasting plasma glucose, fasting insulin (FI), and homeostasis model assessment-estimated insulin resistance (HOMA-IR) (with moderate to high certainty). Curcumin supplementation decreased fasting plasma glucose, FI, and HOMA-IR (with moderate certainty). Fish oil supplementation decreased FI and HOMA-IR, and omega-3 reduced triglycerides (with moderate certainty). There were also improvements in FI after taking vitamin D or inositol supplements (with moderate certainty). Supplementation with fish oil increased adiponectin (with high certainty), and probiotics/synbiotics reduced total testosterone (with moderate certainty). In subfertile women with PCOS, inositol increased the ovulation rates (with moderate certainty).

CONCLUSION

There was no high-certainty evidence that diets alone in women with PCOS improved health or reproductive outcomes. Supplementation with vitamin D, probiotics/synbiotics, omega-3, inositol, and curcumin showed favorable effects on some metabolic outcomes. Probiotics/synbiotics possibly reduces total testosterone, and inositol stimulates ovulation in women with PCOS.

REGISTRATION

PROSPERO registration no. CRD42021251496.

The impact of a group based, remotely delivered weight loss intervention in women with polycystic ovary syndrome on ovulation, quality of life and body composition

Background

Obesity and visceral adiposity are associated with anovulation. The most common cause of anovulatory infertility in women of reproductive age is polycystic ovary syndrome (PCOS). We conducted this formative study to examine the effects of a remotely delivered, group-based lifestyle program for women with overweight/obesity and PCOS on ovulation, PCOS related quality of life (PCOSQ) and body composition.

Methods

Women with anovulatory infertility caused by PCOS (N = 12) were enrolled in a 6-month high-intensity weight management intervention. Participants were asked to attend 45 min., group behavioral lifestyle sessions, delivered remotely by a registered dietitian weekly across the 6-mo. study and comply with a reduced energy diet, increased physical activity (225 min/wk.), and self-monitoring of weight, physical activity and diet. Diets consisted of five portion-controlled meals (three shakes + two entrees), at least five servings of fruits/vegetables, and ad libitum non-caloric beverages daily. Wilcoxon signed-rank tests were used to assess changes in outcomes across the intervention.

Results

Twelve women received the weight loss intervention (mean age = 32.7 ± 4.2 yrs., BMI = 36.8 ± 4.5 kg/m², 92% college educated), and 8 completed the intervention. Eight (67%) women reported ovulating during the intervention with an average time to ovulation of 57 ± 45 days. Women lost an average of 3.85 ± 5.94 kg (p = 0.02), decreased their BMI (−1.61 ± 1.09 kg/m²; p = 0.04), and waist circumference (−4.54 ± 3.03 cm; p = 0.04) over the 6-mo. intervention. Additionally, self-reported menstrual problems measured by PCOSQ significantly improved over the study (p = 0.03).

Conclusion

A multicomponent group-based, remotely delivered, lifestyle intervention delivered remotely is a feasible and potentially scalable option to achieve clinically relevant (>3%) weight loss in women with PCOS.

Clinical trial registration

www.clinicaltrials.gov, identifier: NCT03677362.

Evaluating interventions and adjuncts to optimize pregnancy outcomes in subfertile women: an overview review

BACKGROUND

There is a wealth of information regarding interventions for treating subfertility. The majority of studies exploring interventions for improving conception rates also report on pregnancy outcomes. However, there is no efficient way for clinicians, researchers, funding organizations, decision-making bodies or women themselves to easily access and review the evidence for the effect of adjuvant therapies on key pregnancy outcomes in subfertile women.

OBJECTIVE AND RATIONALE

The aim was to summarize all published systematic reviews (SRs) of randomized controlled trials (RCTs) of interventions in the subfertile population, specifically reporting on the pregnancy outcomes of miscarriage and live birth. Furthermore, we aimed to highlight promising interventions and areas that need high-quality evidence.

SEARCH METHODS

We searched the Cochrane Database of Systematic Reviews and PubMed clinical queries SR filter (inception until July 2021) with a list of key words to capture all SRs specifying or reporting any miscarriage outcome. Studies were included if they were SRs of RCTs. The population was subfertile women (pregnant or trying to conceive) and any intervention (versus placebo or no treatment) was included. We adopted Grading of Recommendations, Assessment, Development and Evaluation (GRADE) for determining the quality of the evidence. Exclusion criteria were overview reviews, reviews that exclusively reported on women conceiving via natural conception, reviews including non-randomized study designs or reviews where miscarriage or live birth outcomes were not specified or reported.

OUTCOMES

The primary outcome was miscarriage, defined as pregnancy loss <24 weeks of gestation. Data were also extracted for live birth where available. We included 75 published SRs containing 121 251 participants. There were 14 classes of intervention identified: luteal phase, immunotherapy, anticoagulants, hCG, micronutrients, lifestyle, endocrine, surgical, pre-implantation genetic testing for aneuploidies (PGT-As), laboratory techniques, endometrial injury, ART protocols, other adjuncts/techniques in the ART process and complementary interventions. The interventions with at least moderate-quality evidence of benefit in reducing risk of miscarriage or improving the chance of a live birth are: intrauterine hCG at time of cleavage stage embryo transfer, but not blastocyst transfer, antioxidant therapy in males, dehydroepiandrosterone in women and embryo medium containing high hyaluronic acid. Interventions showing potential increased risk of miscarriage or reduced live birth rate are: embryo culture supernatant injection before embryo transfer in frozen cycles and PGT-A with the use of fluorescence in situ hybridization.

WIDER IMPLICATIONS

This review provides an overview of key pregnancy outcomes from published SRs of RCTs in subfertile women. It provides access to concisely summarized information and will help clinicians and policy makers identify knowledge gaps in the field, whilst covering a broad range of topics, to help improve pregnancy outcomes for subfertile couples. Further research is required into the following promising interventions: the dose of progesterone for luteal phase support, peripheral blood mononuclear cells for women with recurrent implantation failure, glucocorticoids in women undergoing IVF, low-molecular-weight heparin for unexplained subfertility, intrauterine hCG at the time of cleavage stage embryo or blastocyst transfer and low oxygen concentrations in embryo culture. In addition, there is a need for high-quality, well-designed RCTs in the field of reproductive surgery. Finally, further research is needed to demonstrate the integrated effects of non-pharmacological lifestyle interventions.

Recent Advances in Treatment of Recurrent Spontaneous Abortion

Importance

Recurrent spontaneous abortion (RSA) is a distressing condition experienced by approximately 1% of women trying to conceive. However, the treatment of RSA is a challenge both for clinicians and patients.

Objective

The aim of this review is to discuss the medical and surgical approach to the management of RSA, including those caused by anatomical, genetic, male, infectious, endocrine, and immune factors.

Evidence Acquisition

A literature search using MeSH terms for each topic was undertaken using PubMed, supplemented by hand searching for additional references. Retrieved articles were reviewed, synthesized, and summarized.

Results

Available treatments target hypothetical risk factors for RSA, although the effectiveness of many treatment options is controversial. Intervention should depend on the benefit-to-risk ratio of the proposed treatment.

Conclusions and Relevance

The etiology of RSA is heterogeneous, and patients often lack specific clinical manifestations, which has hindered the progress in predicting and preventing RSA to some extent. Despite intensive workup, at least 50% of couples do not have a clear underlying pathology. In addition, an evidence-based treatment is not available in most patients even if abnormal test results are present. Many new treatment directions are also still actively exploring; empirical and combined multiple treatments are still the main methods.

Target Audience

Obstetricians and gynecologists, family physicians.

Learning Objectives

After completing this activity, the learner should be better able to describe common risk factors for RSA; formulate individualized treatment plans to improve pregnancy outcomes; and propose supportive treatment recommendations for patients with unclear causes.

Pharmacological and non-pharmacological strategies for obese women with subfertility

BACKGROUND

Clinicians primarily recommend weight loss for obese women seeking pregnancy. The effectiveness of interventions aimed at weight loss in obese women with subfertility is unclear.

OBJECTIVES

To assess the effectiveness and safety of pharmacological and non-pharmacological strategies compared with each other, placebo, or no treatment for achieving weight loss in obese women with subfertility.

SEARCH METHODS

We searched the CGF Specialised Register, CENTRAL, MEDLINE, Embase, PsycINFO, and AMED from inception to 18 August 2020. We also checked reference lists and contacted experts in the field for additional relevant papers.

SELECTION CRITERIA

We included published and unpublished randomised controlled trials in which weight loss was the main goal of the intervention. Our primary effectiveness outcomes were live birth or ongoing pregnancy and primary safety outcomes were miscarriage and adverse events. Secondary outcomes included clinical pregnancy, weight change, quality of life, and mental health outcome.

DATA COLLECTION AND ANALYSIS

Review authors followed standard Cochrane methodology.

MAIN RESULTS

This review includes 10 trials. Evidence was of very low to low quality: the main limitations were due to lack of studies and poor reporting of study methods. The main reasons for downgrading evidence were lack of details by which to judge risk of bias (randomisation and allocation concealment), lack of blinding, and imprecision. Non-pharmacological intervention versus no intervention or placebo Evidence is insufficient to determine whether a diet or lifestyle intervention compared to no intervention affects live birth (odds ratio (OR) 0.85, 95% confidence interval (CI) 0.65 to 1.11; 918 women, 3 studies; I² = 78%; low-quality evidence). This suggests that if the chance of live birth following no intervention is assumed to be 43%, the chance following diet or lifestyle changes would be 33% to 46%. We are uncertain if lifestyle change compared with no intervention affects miscarriage rate (OR 1.54, 95% CI 0.99 to 2.39; 917 women, 3 studies; I² = 0%; very low-quality evidence). Evidence is insufficient to determine whether lifestyle change compared with no intervention affects clinical pregnancy (OR 1.06, 95% CI 0.81 to 1.40; 917 women, 3 studies; I² = 73%; low-quality evidence). Lifestyle intervention resulted in a decrease in body mass index (BMI), but data were not pooled due to heterogeneity in effect (mean difference (MD) -3.70, 95% CI -4.10 to -3.30; 305 women, 1 study; low-quality evidence; and MD -1.80, 95% CI -2.67 to -0.93; 43 women, 1 study; very low-quality evidence). Non-pharmacological versus non-pharmacological intervention We are uncertain whether intensive weight loss interventions compared to standard care nutrition counselling affects live birth (OR 11.00, 95% CI 0.43 to 284; 11 women, 1 study; very low-quality evidence), clinical pregnancy (OR 11.00, 95% CI 0.43 to 284; 11 women, 1 study; very low-quality evidence), BMI (MD -3.00, 95% CI -5.37 to -0.63; 11 women, 1 study; very low-quality evidence), weight change (MD -9.00, 95% CI -15.50 to -2.50; 11 women, 1 study; very low-quality evidence), quality of life (MD 0.06, 95% CI -0.03 to 0.15; 11 women, 1 study; very low-quality evidence), or mental health (MD -7.00, 95% CI -13.92 to -0.08; 11 women, 1 study; very low-quality evidence). No study reported on adverse events . Pharmacological versus pharmacological intervention For metformin plus liraglutide compared to metformin we are uncertain of an effect on the adverse events nausea (OR 7.22, 95% CI 0.72 to 72.7; 28 women, 1 study; very low-quality evidence), diarrhoea (OR 0.31, 95% CI 0.01 to 8.3; 28 women, 1 study; very low-quality evidence), and headache (OR 5.80, 95% CI 0.25 to 133; 28 women, 1 study; very low-quality evidence). We are uncertain if a combination of metformin plus liraglutide vs metformin affects BMI (MD 2.1, 95% CI -0.42 to 2.62; 28 women, 1 study; very low-quality evidence) and total body fat (MD -0.50, 95% CI -4.65 to 3.65; 28 women, 1 study; very low-quality evidence). For metformin, clomiphene, and L-carnitine versus metformin, clomiphene, and placebo, we are uncertain of an effect on miscarriage (OR 3.58, 95% CI 0.73 to 17.55; 274 women, 1 study; very low-quality evidence), clinical pregnancy (OR 5.56, 95% CI 2.57 to 12.02; 274 women, 1 study; very low-quality evidence) or BMI (MD -0.3, 95% CI 1.17 to 0.57, 274 women, 1 study, very low-quality evidence). We are uncertain if dexfenfluramine versus placebo affects weight loss in kilograms (MD -0.10, 95% CI -2.77 to 2.57; 21 women, 1 study; very low-quality evidence). No study reported on live birth, quality of life, or mental health outcomes. Pharmacological intervention versus no intervention or placebo We are uncertain if metformin compared with placebo affects live birth (OR 1.57, 95% CI 0.44 to 5.57; 65 women, 1 study; very low-quality evidence). This suggests that if the chance of live birth following placebo is assumed to be 15%, the chance following metformin would be 7% to 50%. We are uncertain if metformin compared with placebo affects gastrointestinal adverse events (OR 0.91, 95% CI 0.32 to 2.57; 65 women, 1 study; very low-quality evidence) or miscarriage (OR 0.50, 95% CI 0.04 to 5.80; 65 women, 1 study; very low-quality evidence) or clinical pregnancy (OR 2.67, 95% CI 0.90 to 7.93; 96 women, 2 studies; I² = 48%; very low-quality evidence). We are also uncertain if diet combined with metformin versus diet and placebo affects BMI (MD -0.30, 95% CI -2.16 to 1.56; 143 women, 1 study; very low-quality evidence) or waist-to-hip ratio (WHR) (MD 2.00, 95% CI -2.21 to 6.21; 143 women, 1 study; very low-quality evidence). Pharmacological versus non-pharmacological intervention No study undertook this comparison.

AUTHORS' CONCLUSIONS

Evidence is insufficient to support the use of pharmacological and non-pharmacological strategies for obese women with subfertility. No data are available for the comparison of pharmacological versus non-pharmacological strategies. We are uncertain whether pharmacological or non-pharmacological strategies effect live birth, ongoing pregnancy, adverse events, clinical pregnancy, quality of life, or mental heath outcomes. However, for obese women with subfertility, a lifestyle intervention may reduce BMI. Future studies should compare a combination of pharmacological and lifestyle interventions for obese women with subfertility.