Impact of body mass index versus physical activity and calorie intake on assisted reproduction outcomes

The role of maternal physical activity on in vitro fertilization outcomes: a systematic review and meta-analysis

PURPOSE

This systematic review is designed to summarize the evidence concerning the impact of maternal physical activity on the reproductive outcomes following assisted reproduction techniques (ART), namely in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI).

METHODS

We searched for eligible studies on PubMed, EMBASE databases and the Cochrane Library from their inception until September 2021. Our primary outcomes were live birth rate and miscarriage, while secondary ones included clinical pregnancy and implantation rates. The quality of the evidence was evaluated using a study-specific adaptation of the Robins I tool.

RESULTS

Quantitative data from 10 cohort studies (CS) and 2 randomized control trials (RCT), involving 3431 women undergoing ART treatments, were included in the analyses. The pooled results exhibited uncertainty regarding the effect of physical activity on live birth rate per woman (OR 1.15, 95% CI 0.92-1.43, p = 0.23, I² = 61%, 9 studies) and miscarriage rates (OR 0.79, 95% CI 0.44-1.43, p = 0.43, I² = 44%, 6 studies). However, physical activity was associated with significantly improved clinical pregnancy rate after ART (OR 1.39, 95% CI 1.08-1.79, p = 0.0009, I² = 68%, 10 studies), whereas implantation rate after ART almost reached statistical significance (OR = 1.95, 95% CI 0.99-3.82, p = 0.05, I² = 77%).

CONCLUSION

The current evidence is still insufficient to firmly conclude on the effect of maternal physical activity on live birth, miscarriage and implantation rates. Although clinical pregnancy rates favored physical activity in this group of patients, these results must be undertaken with caution due to the low quality and the high heterogeneity of the studies included.

Predictive value of cytoplasmic granulation patterns during in vitro fertilization in metaphase II oocytes: part II, donor oocyte cycles

OBJECTIVE

To determine whether the ooplasm granulation patterns of donor oocytes, like those of oocytes from poor-prognosis patients, are predictive of in vitro fertilization (IVF) outcomes.

DESIGN

Retrospective cohort study.

SETTING

Academically affiliated private clinical infertility and research center.

PATIENT(S)

770 fresh and 381 vitrified-thawed metaphase II oocytes from young donors (aged 21.0-34.6 years) used for IVF during 2017-2020.

INTERVENTION(S)

Determination of granulation patterns in every oocyte during intracytoplasmic sperm injection as fine, central, uneven, dispersed, and peripheral (thawed only).

MAIN OUTCOME MEASURE(S)

Fertilization, pregnancy, and live birth rates in fresh and thawed donor oocytes. Both overall and known-outcome analyses were performed for pregnancy and live birth.

RESULT(S)

In fresh donor oocytes, 2 pronuclei rates trended down from 96.1% to 90.2%, 88.9%, and 69.7% from fine to central, uneven, and dispersed granulations; overall pregnancy rates trended down from 50.4% to 29.0%, 17.7%, and 6.9%, as well as live birth rates (43.4%, 21.6%, 12.5%, and 6.4%), from fine to uneven, central, and dispersed granulations. Known pregnancy and known-live birth analyses showed similar findings. Thawed donor oocytes demonstrated similar trends in differences in fertilization, pregnancy, and live birth analyses with relatively worse outcomes. Peripheral granulation, unique to vitrification and thawing, always demonstrated the worst IVF outcomes. Moreover, granulation patterns were relatively disassociated from embryo morphological grades in fresh and largely disassociated in thawed donor oocytes.

CONCLUSION(S)

Predictive values of oocyte granulation patterns for fertilization, pregnancy, and live birth in IVF cycles are even more pronounced in young donors than results in older poor-prognosis patients, further supporting integration of oocyte granulation patterns into embryo selection.

Association between maternal prepregnancy body mass index and pregnancy outcomes following assisted reproductive technology: A systematic review and dose-response meta-analysis

This systematic review investigated dose-response relationship between maternal prepregnancy body mass index (BMI) and pregnancy outcomes following assisted reproductive technology, including clinical pregnancy rate (CPR), miscarriage rate (MR), and live birth rate (LBR). We searched four major databases and finally included 105 studies involving more than 271,632 pregnant women. We performed linear or nonlinear dose-response meta-analyses using random effects models. At per-woman level, pooling of unadjusted estimates shown an inverted J-shaped relationship between maternal BMI and CPR; pooling of adjusted estimates showed a linear association, suggesting statistical association between higher maternal BMI and lower CPR (adjusted OR [aOR] for 5-unit increase in BMI: 0.96, 95%CI: 0.94-0.98). At per-cycle level, linear dose-response relationship was found between maternal BMI and CPR (crude relative risk, RR, [cRR] for 5-unit increase in BMI 0.97, 0.96-0.98; aOR 0.96, 0.94-0.99). Linear dose-response relationship was established between maternal BMI and the outcomes of MR or LBR (higher BMI associated with higher MR [cRR 1.15, 1.08-1.22] and lower LBR [cRR 0.91, 0.88-0.94] at per-woman level). Sensitivity analyses showed no significant changes. In conclusion, there is dose-response relationship between maternal BMI and pregnancy outcomes following assisted reproductive technology. Higher BMI values may suggest suboptimal pregnancy outcomes.

Predictive value of cytoplasmic granulation patterns during in vitro fertilization in metaphase II oocytes: Part I, poor-prognosis patients

OBJECTIVE

To determine whether 4 cytoplasmic granulation patterns of human metaphase II oocytes have a predictive value for in vitro fertilization outcomes.

DESIGN

A retrospective cohort study.

SETTING

An academically affiliated private clinical infertility and research center.

PATIENT(S)

A total of 2,690 consecutive fresh autologous oocytes collected from women aged 41.2 ± 5.0 years between 2017 and 2019.

INTERVENTION(S)

Determination of granulation pattern in every oocyte during intracytoplasmic sperm injection as fine, central, dispersed, and newly introduced uneven granulations.

MAIN OUTCOME MEASURE(S)

Fertilization outcomes (2 pronuclei [2PN], <2PN, and >2PN rates), pregnancy, and live birth rates for different granulation patterns at different ages.

RESULT(S)

Fine granulation produced the highest 2PN rate, followed by central, uneven, and dispersed granulation (91.8%, 83.9%, 77.9%, and 54.8%, respectively). Differences in fertilization were surprisingly relatively independent of age and other variables. Overall, compared with fine granulation, dispersed granulation resulted in lower pregnancy rates (4.6% vs. 10.7%) and known-outcome analysis (1.3% vs. 5.6%) as well as lower live birth rates (3.0% vs. 8.9%) and known-outcome analysis (0.6% vs. 5.6%). The known-outcome analysis demonstrated that uneven granulation had lower live birth rates than fine granulation (2.3% vs. 5.6%). Unexpectedly, the ooplasm granulation patterns were largely disassociated from embryo morphologic grades.

CONCLUSION(S)

We, for the first time, demonstrated that 4 distinct cytoplasmic granulation patterns in metaphase II oocytes had, largely independent of age and other variables, a predictive value for fertilization, pregnancy, and live birth outcomes in in vitro fertilization cycles of poor-prognosis patients. These data suggest that upstream ooplasm granulation patterns deserve closer attention in terms of embryo selection.

Maternal physical activity and sedentary behaviour before and during in vitro fertilization treatment: a longitudinal study exploring the associations with controlled ovarian stimulation and pregnancy outcomes

PURPOSE

To evaluate the association of objectively measured physical activity (PA) and sedentary behaviour before and during in vitro fertilization (IVF) with controlled ovarian stimulation (COS) and pregnancy outcomes.

METHODS

This longitudinal study involved 107 infertile women undergoing IVF treatment. PA and sedentary behaviour were measured for 14 consecutive days using accelerometry as follows: (1) before IVF treatment, (2) during IVF at the implantation time, immediately after embryo transfer, and (3) after positive pregnancy test. Total screen time was assessed by questionnaires. COS results were measured as the number of oocytes and embryos obtained, and the study outcomes included positive hCG, clinical pregnancy, and live birth.

RESULTS

Compared with baseline activity levels, women significantly reduced their PA and increased sedentary behaviour during IVF (p ≤ 0.001). Higher average PA, light PA, and ratio between breaks in every ≥ 30-min blocks of sedentary time showed positive associations, while sedentary time, number, and time accumulated in blocks of ≥ 30 min of sedentary time associated negatively with oocyte and embryo counts (all p < 0.05). Women with high total screen time during non-work days (≥ 7 h) obtained 4.7 oocytes (p = 0.005) and 2.8 embryos (p = 0.008) less in COS. PA and sedentary behaviour before and during IVF did not affect the positive hCG, clinical pregnancy, and live birth outcomes.

CONCLUSION

Our study results suggest that higher time spent in PA and lower time spent in sedentary behaviour before entering assisted reproduction is associated with better COS outcomes, while activity levels before and during IVF do not affect the implantation, pregnancy, and live birth outcomes.

Determining the association between physical activity prior to conception and pregnancy rate: A systematic review and meta-analysis of prospective cohort studies

We investigated the association between physical activity (PA) before pregnancy and pregnancy rate according to intensity and amount of exercise. Eleven prospective cohort studies were included in this meta-analysis. Any amount of moderate-intensity PA was associated with a statistically higher rate of pregnancy compared to that in patients with no PA (p < .05). Any amount of vigorous PA was associated with decreased pregnancy rate; regular PA was associated with decreased infertility (p > .05). In contrast, vigorous PA was associated with increased infertility (p > .05). Therefore, women who are preparing for pregnancy are recommended to perform regular, moderate-intensity PA.

A systematic review and meta-analysis of lifestyle and body mass index predictors of successful assisted reproductive technologies

OBJECTIVE

Lifestyle (smoking, drinking alcohol) and body mass index (BMI) predictors of successful outcomes in assisted reproductive technology (ART) treatments were examined in this meta-analysis.

METHOD

A bibliographic search was undertaken using six databases. The review was informed by PRISMA/MOOSE guidelines. Meta-analytic data were analysed using random effects models.

RESULTS

We included 77 studies examining effects of BMI, smoking and drinking alcohol. Patients with a BMI< =24.9 were significantly more likely to achieve LB/pregnancy than with BMI> =25 OR = 1.219 (95% CI:1.128-1.319, z = 4.971, p < .001; I² = 53.779%, p = .001). Non-smokers were significantly more likely to achieve a LB or pregnancy than smokers OR = 1.457 (95% CI:1.228-1.727, z = 4.324, p < .001; I² = 51.883; p = .001). Meta-regression revealed the number of embryos transferred significantly moderated the effects of smoking on ART outcomes, and there was a trend indicating primary infertility and high BMI were also significant moderators. The evidence for drinking alcohol was inconclusive due to the small number of studies.

CONCLUSIONS

This meta-analysis confirms that ART treatment success can be predicted with lifestyle factors. Further, non-smokers' relative odds of pregnancy/live birth increase as more embryos were transferred but there was a trend that the odds of pregnancy/live birth decrease with primary infertility and high BMI.

The correlation between raised body mass index and assisted reproductive treatment outcomes: a systematic review and meta-analysis of the evidence

Background

Public funding for fertility services within the United Kingdom is limited, and therefore, strict guidance exists regarding who can be offered treatment under the National Health Service (NHS). Body mass index (BMI) is a universal criteria adopted by both the public and private sector.

This study addresses an important aspect of the impact of a raised BMI on fertility treatment outcomes. We standardise the analysis of the data by only including studies incorporating the WHO BMI criteria; the current reference point for clinicians and clinical commissioning groups in ascertaining which group of patients should receive treatment. This study is an update of the previous systematic review performed in 2010, with the inclusion of a larger number of cycles from central databases such as the Society for Assisted Reproductive Technology (SART).

Methods

An electronic literature search was conducted through the Cochrane, Medline and Embase libraries. Data extraction for each outcome measure was pooled and expressed as an odds ratio with 95% confidence intervals. Where clinical heterogeneity was evident, the random effects model was used to calculate the risk ratio and a fixed effects model was used for the remaining studies. A p value < 0.05 was considered statistically significant.

Results

A total of 49 studies have been identified and included in this systematic review. Overweight and obese (BMI ≥ 25 kg/m²) women have a statistically significant lower live birth rate (OR 0.81, 95% CI 0.74–0.89, p < 0.00001) following Assisted Reproductive Technology (ART) when comparisons are drawn to women with a normal BMI. An increase is also demonstrated in the number of miscarriages experienced by women with a BMI ≥ 30 kg/m² (OR 1.52, 95% CI 1.28–1.81, p < 0.00001).

Conclusion

Although this review concludes that a clear impact of BMI on ART outcomes is demonstrated, there remains questions as to the pathophysiology underlying these differences. This review supports the government’s stringent criteria regarding BMI categories under which NHS funding is made available for ART, through a clear description of poor reproductive outcomes in women with a BMI ≥ 30 kg/m².

Maternal physical activity before IVF/ICSI cycles improves clinical pregnancy rate and live birth rate: a systematic review and meta-analysis

OBJECTIVE

This meta-analysis was aimed to evaluate the association between maternal physical activity before IVF/ICSI cycles and reproductive outcomes.

METHODS

We searched databases of PubMed, EMBASE and Web of Science electronic databases, and ongoing trials up to November 2017 to identify studies that focused on the relationship between maternal physical activity before IVF/ICSI cycles and reproductive outcomes, including implantation rate, clinical pregnancy rate, miscarriage rate and live birth rate. Odds ratio (OR) with 95% confidence intervals, were calculated to assess the results of each outcome.

RESULTS

Eight published studies encompassing 3683 infertile couples undergoing IVF/ICSI treatment were included into the analysis. There was an increasing, but not statistically significant, trend in implantation rate for physically active women when compared with physically inactive women (OR = 1.95, 95% CI 0.99-3.83, I2 = 77%). No significant difference was found in miscarriage rate between physically active women and physically inactive women (OR = 0.76, 95% CI 0.41-1.44, I2 = 49%). However, rates of clinical pregnancy and live births in physically active women were significantly higher than those in physically inactive women (OR = 1.96, 95% CI 1.40, 2.73, I2 = 42% and OR = 1.95, 95% CI 1.06-3.59, I2 = 82%, respectively). Subgroup analysis helped to confirm these results.

CONCLUSIONS

Female physical activity before IVF/ICSI cycles was associated with increased rates of clinical pregnancy and live births, whereas only a small but not statistically significant increase was found in implantation rate, and no effect was shown on miscarriage rate.

Pregnancy complications in spontaneous and assisted conceptions of women with infertility and subfertility factors. A comprehensive review

In the literature, there is growing evidence that assisted reproductive techniques increase the risk of pregnancy complications in subfertile couples. Moreover, many concomitant preconception risk factors for subfertility are frequently present in the same subject and increase the risk of pregnancy complications. This review aimed to summarize in a systematic fashion the best current evidence regarding the effects of preconception maternal factors on maternal and neonatal outcomes. A literature search up to March 2016 was performed in IBSS, SocINDEX, Institute for Scientific Information, PubMed, Web of Science and Google Scholar. An evidence-based hierarchy was used to determine which articles to include and analyse. Available data show that the risk of pregnancy complications in spontaneous and assisted conceptions is likely multifactorial, and the magnitude of this risk is probably very different according specific subgroups of patients. Notwithstanding the only moderate level and quality of the available evidence, available data suggest that the presence and the treatment of specific preconception cofactors of subfertility should be always taken into account both in clinical practice and for scientific purposes.

Health beliefs and stages of changes to improve behaviors among obese and overweight women undergoing preconception care

Background:

Beginning and continuing pregnancy with obesity and being overweight has some known side effects for the mother and the fetus. Preventing these complications requires medical interventions before pregnancy. Because designing health improvement interventions requires understanding of the related factors of the behavior, the aim of this study was to determine the relation between health beliefs of women regarding the risks of obesity for pregnancy and stages of behavioral changes in women under preconception care.

Materials and Methods:

This study was a cross-sectional study that was conducted on 120 obese and overweight women under preconception care. Health belief structures including perceived sensitivity/intensity, perceived benefits, perceived barriers, and perceived self-efficacy were measured using a questionnaire, and its relation with stages of nutrition and physical activity behavior changes was evaluated according to a transtheoretical model.

Results:

Results showed a significant correlation between the stage of nutrition behavioral change and perceived sensitivity/intensity, perceived benefits, and self-efficacy (P < 0.05). In addition, the stage of physical activity behavioral change showed a negative and significant correlation with perceived barriers and a positive and low-to-moderate significant correlation with other health belief structures (P < 0.05). Furthermore, the relation of perceived sensitivity/intensity with perceived benefits and self-efficacy was positive and significant, and that with perceived barriers was negative and significant (P < 0.01).

Conclusions:

Results showed that a health belief model could be a predictor of weight adjustment behaviors including nutrition and physical activity behaviors. Therefore, educational interventions based on a health belief model could be effective for improvement of these behaviors in obese and overweight women under preconception care.

Physical activity and body mass index among women who have experienced infertility

INTRODUCTION

The experience of infertility is a common medical condition in the developing countries. The aim of this retrospective epidemiologic study was to determine fertility status and parity in Babol, Iran and then identify physical activity and body mass index (BMI) among women who have experienced infertility.

MATERIAL AND METHODS

A total of 1,081 women aged 20-45 years were selected using cluster sampling. The current physical activity was measured using the original International Physical Activity Questionnaire short form. Lifestyle factors were compared between those who had experienced infertility (n = 168) and the rest of the women. A face-to-face household interview was conducted using a specially designed interview questionnaire.

RESULTS

After adjusting for suspected confounding factors, women with infertility experience had a 4.8-fold increased risk of obesity (OR = 2.02, CI = 0.70, 5.84) and almost a 3.8-fold increased risk of being overweight (OR = 2.11, CI = 0.72, 6.17) compared to women without infertility. No significant differences were found in Met-minutes of sedentary activity, intensity of walking, moderate, vigorous, and total physical activity, self-reported dietary intake, exercise, and level of physical activity between women with and without experience of infertility.

CONCLUSIONS

Since both obesity and infertility are increasing public health issues in Iranian women, more attention should be paid to lifestyle behaviors, especially gaining weight in women who have experienced infertility.