The effects of exercise conditioning in normal and overweight pregnant women on blood pressure and heart rate variability

Exercise Intervention to Mitigate the Cardiovascular Sequence of Pregnancy Complications

Pregnancy issues such as gestational hypertension, preeclampsia, and gestational diabetes mellitus (GDM) are significant contributors to long-term cardiovascular diseases (CVDs) in women. Recent research has proved the impact of exercise on improving cardiovascular outcomes, particularly in women with pregnancy-related disorders. This review explores the outcomes of various exercise interventions on cardiovascular health in pregnant women. Among these, aerobic exercise has been widely studied, with results from observational studies and randomized controlled trials (RCTs) showing its positive outcomes on cardiovascular health in pregnant women, especially with complications. It has been found that regular aerobic exercise has been associated with reduced hypertension and improved endothelial function, particularly in women with a history of preeclampsia. Evidently, aerobic exercise results in better blood pressure regulation and enhanced vascular health that directly attends to the risk of cardiovascular diseases associated with pregnancy complications. Another form of exercise is resistance training, which despite being studied less, has shown potential benefits as well. Some advantages of resistance exercise have been found to improve muscle strength and overall enhancement in metabolic control. This is important, especially in women with GDM whereby improvement in insulin sensitivity reduces the overall risk of type 2 diabetes and future CVDs. Combined exercise that incorporates both aerobic and resistance elements has been known to offer the most comprehensive benefits. Various studies suggest that a combinatory approach maximizes the positive cardiovascular effects. Practicing women have experienced better overall heart health, with improved blood pressure regulation, enhanced endothelial function, and reduced metabolic risks. However, despite these findings, there are challenges such as small sample sizes and limited follow-up durations that hinder the generalizability of current research. Importantly, previous studies targeting exercise interventions for women experiencing complications during pregnancy have been limited in evidence by small sample sizes, short follow-ups, and lack of diversity. Such broader, more diverse populations were needed to reflect the various health risks and responses to exercise. Future research must include multi-center RCTs, diverse exercise regimens, and digital health tools for monitoring exercise adherence. This warrants future large-scale, multicenter trials that are necessary to establish more definitive evidence. Additionally, clinicians should consider including tailored exercise programs in care plans for women with pregnancy complications to mitigate long-term cardiovascular risks.

Exercise effects on maternal vascular health and blood pressure during pregnancy and postpartum: a systematic review and meta-analysis

AIMS

This systematic review aimed to assess the effects of exercise training during pregnancy and the postpartum period on maternal vascular health and blood pressure (BP).

METHODS AND RESULTS

The outcome of interest was pulse wave velocity (PWV), flow-mediated dilation (FMD), and BP from pregnancy to 1-year postpartum. Five databases, including Ovid MEDLINE, EMBASE, CINAHL, Web of Science, and Cochrane Library, were systematically searched from inception to August 2023. Studies of randomized controlled trials (RCTs) comparing the effects of prenatal or postpartum exercise to a non-exercise control group were included. The risk of bias and the certainty of evidence were assessed. Random-effects meta-analyses and sensitivity analyses were conducted. In total, 20 RCTs involving 1221 women were included. Exercise training, initiated from Week 8 during gestation or between 6 and 14 weeks after delivery, with the programme lasting for a minimum of 4 weeks up to 6 months, showed no significant impact on PWV and FMD. However, it resulted in a significant reduction in systolic BP (SBP) [mean difference (MD): -4.37 mmHg; 95% confidence interval (CI): -7.48 to -1.26; P = 0.006] and diastolic BP (DBP) (MD: -2.94 mmHg; 95% CI: -5.17 to -0.71; P = 0.01) with very low certainty. Subgroup analyses revealed consistent trends across different gestational stages, types of exercise, weekly exercise times, and training periods.

CONCLUSION

Exercise training during pregnancy and the postpartum period demonstrates a favourable effect on reducing maternal BP. However, further investigations with rigorous methodologies and larger sample sizes are needed to strengthen these conclusions.

Autonomic modulation of heart rate during physical activity in pregnant women: A systematic review of literature

BACKGROUND

There are important physiological changes in the heart rate autonomic modulation in pregnant women and these changes may affect the way their bodies respond to exercise stimulus. The objective of this review is to verify the physical exercise influence on autonomic modulation of heart rate in pregnant women.

METHODS

This study is a Systematic Review. The electronic databases used to search for the studies were Cochrane Library, MEDLINE via PUBMED, Regional Health Portal and EMBASE. Experimental studies that evaluated heart-rate variability in pregnant women practicing physical exercises were included. And articles that addressed only fetal heart-rate variability, case reports, congress abstracts, clinical trial protocols without results, preprints, and gray literature were excluded. There were no language or publication year restrictions. The descriptors used in the Search were Cardiac Chronotropism, Sympathetic Nervous System, Pregnancy, and Physical Exercise. For statistical analysis, the fixed effect model was used.

RESULTS

A total of 3106 articles were found, and 12 studies were included, which 5 were nonrandomized clinical trials, 4 were randomized clinical trials, and 3 were cross-sectional studies. Three hundred and four pregnant women were included in the studies. The application of physical exercise was varied, but in general they used aerobic exercises and with increased variability of the heart rate and reflex on the autonomic modulation of heart rate.

CONCLUSION

Most studies demonstrate benefits heart rate in pregnant women, but limited research makes it hard to compare specific types of exercise and larger studies are needed to identify the best exercise.

Influence of Physical Activity during Pregnancy on Maternal Hypertensive Disorders: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Gestational hypertension is a notable concern with ramifications for maternal and fetal health. Preemptive measures, including physical activity (PA), are crucial. There is a pressing need for comprehensive investigations into the impact of various forms of PA on hypertensive disorders. A systematic review and meta-analysis (CRD42022372468) following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines was performed. Our review exclusively considered randomized clinical trials (RCTs) between 2010 and 2023, using the following databases: EBSCO, including Academic Search Premier, Education Resources Information Center, PubMed/MEDLINE, SPORTDiscus, and OpenDissertations; Clinicaltrials.gov; Web of Science; Scopus; the Cochrane Database of Systematic Reviews; and the Physiotherapy Evidence Database (PEDro). The primary outcome was hypertensive disorders occurring during pregnancy (14 studies). Diagnosed preeclampsia (15 studies) and blood pressure levels were also examined (17 studies). PA during pregnancy was significantly associated with a reduced risk of hypertensive disorders (RR = 0.44, 95% CI = 0.30, 0.66). The data also indicate a positive correlation between PA during pregnancy and both systolic (MD = -2.64, 95% CI = -4.79, -0.49) and diastolic (MD = -1.99, 95% CI = -3.68, -0.29) blood pressure levels. The relationship between PA and the incidence of diagnosed preeclampsia did not demonstrate a statistically significant association (RR = 0.81, 95% CI = 0.59, 1.11; p = 0.20). Random effects were used for all analyses. PA during pregnancy promises to improve maternal health by reducing the risk of gestational hypertension and positively affecting systolic and diastolic blood pressure.

A socio-ecological model of factors influencing physical activity in pregnant women: a systematic review

Physical activity (PA) is safe for most pregnant women, improving both maternal fitness and birth outcomes. Despite evidence of benefits, most pregnant women eliminate or reduce PA during pregnancy. This systematic review aimed to analyze the factors affecting maternal PA during pregnancy with reference to a socio-ecological model. A systematic search of relevant published studies between 2001 and 2022 was conducted through PubMed, Scopus, Web of Science, Academic Search Ultimate, Medline, and SPORTDiscus with full text via the EBSCO platform. A total of 32 studies that met the inclusion criteria were reviewed. The findings revealed that various study designs can lead to different outcomes in terms of what is identified as a PA facilitator or barrier. The factors that positively influenced PA in pregnant women were: higher levels of education, knowledge, and skills, as well as access to mass media. Conversely, lower levels of education, lack of knowledge and skills, low income, pregnancy discomforts, limited time, safety concerns, and societal perceptions of PA in pregnancy acted as barriers. Additionally, family, colleagues/friends, and partners could either support or hinder PA. Factors affecting overall maternal PA were somewhat different from those affecting the moderate-to-vigorous intensity of PA. Pregnant women receive little organizational and policy support. There is an urgent need to provide accessible information and resource systems for pregnant women. Since most pregnant women are motivated to engage in PA and susceptible to family advice, interventions should not be limited only to pregnant women, but should involve a family member, especially partners. There is a need to take global, systemic actions to promote an active lifestyle in pregnancy. Addressing safety concerns related to PA during pregnancy should be a significant part of these promotional activities.

Effects of physical exercise on blood pressure during pregnancy

Objective

Effect of physical exercise on pregnant women currently has become a hot topic in prenatal health care. In this study, A meta-analysis was conducted on account of Randomized Controlled Trial (RCT). It focused on evaluating the effect of physical exercise intervention on blood pressure so that could provide certain evidence for health care during pregnancy.

Methods

Results of relevant studies were retrieved from PubMed, Embase, Web of Science and the Cochrane Library, and all of these included studies were evaluated according to the Cochrane collaboration’s tool for assessing the risk of bias. Stata 15.1 was used for meta-analysis, and mean difference (MD) was used as statistic for pooled analysis. The effect values were combined by conventional meta-analysis and Bayesian meta-analysis respectively, and the consistency of pooled results was considered as well.

Results

A total of 18 RCT studies were included in the quantitative analysis. The conventional meta-analysis showed differences in blood pressure between intervention group and control group (P < 0.05). Systolic and diastolic blood pressures of intervention group were 3.19 mmHg (95% CI: -5.13, -1.25) and 2.14 mmHg (95% CI: -4.26, -0.03) lower than that of control group, respectively. Bayesian meta-analysis showed that both systolic and diastolic pressure among intervention group decreased by 3.34 mmHg (95% CrI: -5.15, -1.56) and 2.14 mmHg (95% CrI: -3.79, − 0.50), respectively. Subgroup analysis supported that as long as healthy pregnant women participated in exercises, their blood pressure could be slightly regulated, while hypertension susceptible pregnant women significantly lowered blood pressure.

Conclusion

Exercise intervention during pregnancy is beneficial to lower or normalize blood pressure, and this research provides clues for follow-up studies.

Effects of aerobic, strength, and combined training during pregnancy in the blood pressure: A systematic review and meta-analysis

Gestational hypertension can lead to fetal complications, and, if untreated, high blood pressure during pregnancy may cause eclampsia and even death in the mother and fetus. Exercise is a strategy for preventing blood pressure disorders. There is little knowledge about the physiological impacts of different physical types of training on blood pressure during pregnancy. For that, this meta-analysis aimed to compare the effects of different physical exercise modalities (i.e., aerobic training-AT, strength training-ST, and combined training-AT + ST) on systolic blood pressure (SBP) and diastolic blood pressure (DBP) of pregnant women. A search was performed on PUBMED, LILACS, CINAHL, Sport discus, EMBASE, SCOPUS, and Cochrane Central Register of Controlled Trials to identify researchers. From 3,450 studies, 20 and 19 were included in the qualitative and quantitative analyses. AT studies presented a medium effect size (ES) on SBP [-0.29 (-2.95 to 2.36) p = 0.83], with substantial heterogeneity (I2 = 64%), and had a large impact on DBP [-1.34 (-2.98 to 0.30) p = 0.11], with moderate heterogeneity (I2 = 30%). ST researchers showed a large ES on SBP [-1.09 (-3.66 to 1.49) p = 0.41], with a reduced heterogeneity (I2 = 0%), and a medium ES on DBP [-0.26 (-2.77 to 2.19) p = 0.83] with moderate heterogeneity (I2 = 38%). AT + ST studies had a large ES on SBP [-1.69 (-3.88 to 0.49) p = 0.13] and DBP [-01.29 (-2.26 to 0.31) p = 0.01] with considerable (I2 = 83%) and moderate heterogeneity (I2 = 47%), respectively. These findings are essential for developing new research protocols to avoid gestational hypertension and preeclampsia. AT + ST had a large impact on the SBP and DBP reduction; however, there is a need for more similar procedures to reduce heterogeneity between studies, promoting consensual results. Systematic Review Registration: [PROSPERO], identifier [CRD42021256509].

Relationship of health practices with depression and maternal-fetal attachment in adolescent pregnant women: A prospective study

AIM

To determine the relationship of health practices with depression and maternal-fetal attachment in adolescent pregnant women.

METHODS

This prospective study was conducted on 316 adolescent pregnant women with medical records at the health centers in Tehran, Iran. The participants were selected through the complete enumeration. Data were collected using the socio-demographic and obstetrics questionnaire, the Health Practices Questionnaire-II (HPQ-II), the Edinburgh Postnatal Depression Scale (EPDS), and the Cranley's Maternal-Fetal Attachment Scale (MFAS). The data were analyzed with the Pearson correlation test, the independent t-test, one-way ANOVA, and the general linear model.

RESULTS

The mean scores of health practices, depression, and maternal-fetal attachment were 135.3 (SD 9.1, range 34-170), 10.1 (SD 5.4, range 0-30), and 91.6 (SD 8.6, range 24-120), respectively. The results of Pearson correlation test showed that health practices had a significant relationship with depression (r = -0.29) and maternal-fetal attachment (r = 0.37). Results of general linear model showed that an increase in the health practices score led to a significant decrease in depression score during pregnancy [β = -0.10; 95% CI: -0.17 to -0.04] and a significant increase in maternal-fetal attachment score [β = 0.30; 95% CI: 0.19 to 0.40].

CONCLUSION

There is significant relationship between health practices and depression, as well as maternal-fetal attachment in adolescent pregnant women. Therefore, intervention to improve one of them may improve the other one(s).

Walking for hypertension

BACKGROUND

Increased physical activity has been recommended as an important lifestyle modification for the prevention and control of hypertension. Walking is a low-cost form of physical activity and one which most people can do. Studies testing the effect of walking on blood pressure have revealed inconsistent findings.

OBJECTIVES

To determine the effect of walking as a physical activity intervention on blood pressure and heart rate.

SEARCH METHODS

We searched the following databases up to March 2020: the Cochrane Hypertension Specialised Register, CENTRAL (2020, Issue 2), Ovid MEDLINE, Ovid Embase, CINAHL, PsycINFO, SPORTDiscus, PEDro, the WHO International Clinical Trials Registry Platform, and ClinicalTrials.gov. We also searched the following Chinese databases up to May 2020: Index to Taiwan Periodical Literature System; National Digital Library of Theses and Dissertation in Taiwan; China National Knowledge Infrastructure (CNKI) Journals, Theses & Dissertations; and Wanfang Medical Online. We contacted authors of relevant papers regarding further published and unpublished work. The searches had no language restrictions.

SELECTION CRITERIA

Randomised controlled trials of participants, aged 16 years and over, which evaluated the effects of a walking intervention compared to non-intervention control on blood pressure and heart rate were included.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Where data were not available in the published reports, we contacted authors. Pooled results for blood pressure and heart rate were presented as mean differences (MDs) between groups with 95% confidence intervals (CIs). We undertook subgroup analyses for age and sex. We undertook sensitivity analyses to assess the effect of sample size on our findings.

MAIN RESULTS

A total of 73 trials met our inclusion criteria. These 73 trials included 5763 participants and were undertaken in 22 countries. Participants were aged from 16 to 84 years and there were approximately 1.5 times as many females as males. The characteristics of walking interventions in the included studies were as follows: the majority of walking interventions was at home/community (n = 50) but supervised (n = 36 out of 47 reported the information of supervision); the average intervention length was 15 weeks, average walking time per week was 153 minutes and the majority of walking intensity was moderate. Many studies were at risk of selection bias and performance bias. Primary outcome We found moderate-certainty evidence suggesting that walking reduces systolic blood pressure (SBP) (MD -4.11 mmHg, 95% CI -5.22 to -3.01; 73 studies, n = 5060). We found moderate-certainty evidence suggesting that walking reduces SBP in participants aged 40 years and under (MD -4.41 mmHg, 95% CI -6.17 to -2.65; 14 studies, n = 491), and low-certainty evidence that walking reduces SBP in participants aged 41 to 60 years (MD -3.79 mmHg, 95% CI -5.64 to -1.94, P < 0.001; 35 studies, n = 1959), and those aged 60 years of over (MD -4.30 mmHg, 95% CI -6.17 to -2.44, 24 studies, n = 2610). We also found low certainty-evidence suggesting that walking reduces SBP in both females (MD -5.65 mmHg, 95% CI -7.89 to -3.41; 22 studies, n = 1149) and males (MD -4.64 mmHg, 95% CI -8.69 to -0.59; 6 studies, n = 203). Secondary outcomes We found low-certainty evidence suggesting that walking reduces diastolic blood pressure (DBP) (MD -1.79 mmHg, 95% CI -2.51 to -1.07; 69 studies, n = 4711) and heart rate (MD -2.76 beats per minute (bpm), 95% CI -4.57 to -0.95; 26 studies, n = 1747). We found moderate-certainty evidence suggesting that walking reduces DBP for participants aged 40 years and under (MD -3.01 mmHg, 95% CI -4.44 to -1.58; 14 studies, n = 491) and low-certainty evidence suggesting that walking reduces DBP for participants aged 41 to 60 years (MD -1.74 mmHg, 95% CI -2.95 to -0.52; 32 studies, n = 1730) and those aged 60 years and over (MD -1.33 mmHg, 95% CI -2.40 to -0.26; 23 studies, n = 2490). We found moderate-certainty evidence that suggests walking reduces DBP for males (MD -2.54 mmHg, 95% CI -4.84 to -0.24; 6 studies, n = 203) and low-certainty evidence that walking reduces DBP for females (MD -2.69 mmHg, 95% CI -4.16 to -1.23; 20 studies, n = 1000). Only 21 included studies reported adverse events. Of these 21 studies, 16 reported no adverse events, the remaining five studies reported eight adverse events, with knee injury being reported five times.

AUTHORS' CONCLUSIONS

Moderate-certainty evidence suggests that walking probably reduces SBP. Moderate- or low-certainty evidence suggests that walking may reduce SBP for all ages and both sexes. Low-certainty evidence suggests that walking may reduce DBP and heart rate. Moderate- and low-certainty evidence suggests walking may reduce DBP and heart rate for all ages and both sexes.

Is pelvic floor muscle training able to alter the response of cardiovascular autonomic modulation and provide a possible cardiovascular benefit to pregnant women?

AIMS

To evaluate the acute and chronic effect of an exercise protocol of pelvic floor muscles (PFMs) contraction on the heart period (HP) and systolic arterial pressure (SAP) variabilities and baroreflex sensitivity (BRS) at rest in pregnant women; and to evaluate if this progressive exercise protocol was well-tolerated by the pregnant women studied.

METHODS

We evaluated 48 women at 18 weeks of pregnancy by vaginal palpation, vaginal manometry, and cardiopulmonary exercise test. They were divided in control (CG; 31.75 ± 3.91 years) and training groups (TG; 30.71 ± 3.94 years). At 19 and 36 weeks of pregnancy, electrocardiogram and noninvasive peripheral SAP data were collected at rest before and after 10 PFM contractions. TG performed PFMT from the 20th to the 36th week. HP and SAP variabilities were analyzed by spectral and symbolic analysis. The baroreflex was evaluated by cross-spectral analysis between the HP and SAP series.

RESULTS

The groups did not differ in relation to VO₂ , HP and SAP variabilities, and BRS at the beginning of the protocol. TG increased the endurance of the PFM after training. PFM contraction did not change the HP and SAP variabilities, and BRS at the 18th week. After the training, the TG presented lower SAP mean, lower BF of SAP variability, and higher BRS than CG.

CONCLUSIONS

Acute PFM contractions did not alter HP and SAP variabilities and BRS, but PFMT resulted in a lower SAP mean and higher BRS in trained pregnant when compared to the untrained.

Predictors of health practices among a group of Iranian adolescent pregnant women: a cross-sectional study

Introduction The health practices of pregnant women can affect maternal and fetal health, and pregnancy outcomes. Understanding the predictors of health practices in adolescent pregnant women can help improve these practices. The present study aimed to determine the predictors of health practices in adolescent pregnant women. Materials and methods This cross-sectional study was conducted on 316 adolescent pregnant women in health centers of Tehran (capital of Iran). The participants were selected through the census method. The data were collected using the socio-demographic, obstetrics and health practices questionnaires and analyzed using Pearson correlation coefficient, independent t-test, one-way ANOVA, and general linear model. Results The mean score of health practice was 135.29 ± 9.08, ranging from 34 to 170. The highest and the lowest mean score pertained to the avoidance of harmful drugs and opiates subscale (29.79) and the balance of rest and exercise subscale (13.15), respectively. The general linear model showed that a lower level of education, a history of abortion, lack of involvement in pre-pregnancy counseling, and delayed attendance for prenatal care, reduced the health practice score. However, high level of emotional support from the spouse increased the health practice score. Conclusions The findings highlighted the factors effective on health practices including involvement in pre-pregnancy counseling, early prenatal care and emotional support for the adolescent pregnant woman.

Determination of minimal recording period to assess resting heart rate variability during pregnancy

Traditionally, resting heart rate variability (rHRV) is measured for 10 min using the last 5 min for analyses (e.g., criterion period). It is unknown whether the measurement period can be shortened in pregnant women as there are currently no established standards. We aimed to compare shorter time segments (e.g., from the 1st to 10th minutes) of the parasympathetic index natural logarithm transformation of root mean square of successive R–R differences (Ln rMSSD) with the criterion period in pregnant and nonpregnant women. Twelve pregnant (age: 30.8 ± 3.4 years; gestational age: 20.1 ± 5.0 weeks) and 15 nonpregnant women (age: 29.8 ± 4.0 years) were included. rHRV was measured using a portable heart rate monitor for 10 min while sitting. Ln rMSSD difference/agreement between shorter time segments and criterion period was analyzed. The result observed between the 4th–5th minutes was the shortest time segment not different from/highly agreed with the criterion period in pregnant women (difference [95% confidence interval (CI)]: −0.10 [−0.22 to 0.02]/bias ± 1.96 × SD: −0.06 [−0.38 to 0.25]). In nonpregnant women, the 2nd–3rd-minute segment was the shortest with similar results (difference [95% CI]: −0.04 [−0.15 to 0.07]/bias ± 1.96 × SD: −0.03 [−0.39 to 0.32]). The Ln rMSSD was found to be stable from the 5th–10th minutes and the 3rd–10th minutes in pregnant and nonpregnant women, respectively. A shortened rHRV assessment can increase its applicability in clinical/exercise-training settings.

Novelty Ln rMSSD can be measured for 5 min in pregnant women, with the last 1-min segment analyzed. The last 1-min segment from 3 min can be used for rHRV measurement in nonpregnant women. The shortened rHRV assessment can facilitate its applicability in clinical/exercise-training settings.

Physical activity and associated factors among pregnant women in Ethiopia: facility-based cross-sectional study

BACKGROUND

Regular physical activity (PA) has health benefits, including reducing the risk of complications during pregnancy. In Ethiopia, little is known about PA status and its determinants among pregnant women. The purpose of this study was to assess PA status and associated factors among pregnant women attending antenatal care at public and private health facilities in Mekelle, Ethiopia.

METHODS

A facility-based cross-sectional study was conducted. Data was collected from 299 pregnant women using a structured questionnaire. Study participants were selected using a simple random sampling technique. A binary logistic regression was modeled to investigate the statistical significance of independent variables with PA status during pregnancy. Factors associated with PA status were estimated using adjusted odds ratios with 95% confidence intervals and statistical significance was declared at p-value < 0.05.

RESULTS

79.3% of the study participants were classified as sedentary. The age group of 26-35 years (AOR: 2.69, 95% CI: 1.07-6.78), attending non-formal education (AOR: 13.50, 95% CI: 2.65-68.91), and women who did not work outside the home (AOR: 5.23, 95% CI: 1.34-20.38) were significantly associated with a higher risk of sedentary activity status. Pregnant women who were married (AOR: 0.26, 95% CI: 0.09-0.73), had two children (AOR: 0.13, 95% CI: 0.03-0.59), traveled an hour or more to health facilities (AOR: 0.31, 95% CI: 0.11-0.89) were protected from being sedentary.

CONCLUSION

Sedentary PA status was highly prevalent during pregnancy. Pregnant women in the age group of 26-35 years, with a non-formal education, and women who did not work outside the home had a greater risk of reporting being sedentary. Those who were married, had two children, and traveled an hour or more to health facilities were less likely to be sedentary. Stakeholders (Tigrai regional health bureau, Mekelle University, local NGOs working with pregnant women and societies at large) should give higher emphasis on designing appropriate strategies including educational interventions to overcome barriers to PA during pregnancy.

Adolescent pregnant women's health practices and their impact on maternal, fetal and neonatal outcomes: a mixed method study protocol

Background

Considering that individuals’ health practices can affect the health of both mothers and babies, this study is designed to: (a) assess adolescent pregnant women’s health practices and their relationship with maternal, fetal, and neonatal outcomes; (b) explore the perception of adolescent pregnant women about their own health practices; and (c) recommend some strategies to improve adolescent pregnant women’s health practices during pregnancy.

Methods/design

This mixed-method study with the sequential explanatory design has two phases. The first phase (quantitative phase) is a prospective study to assess the adolescent pregnant women’s health practices and its relationship with maternal, fetal, and neonatal outcomes who live in Tehran, the capital city of Iran. A cluster sampling method will be used to select 316 adolescent pregnant women who visit health centers in Tehran. The second phase is a qualitative study designed to explore the adolescent pregnant women’s perception of important aspects and factors of health practices that can affect their health outcomes. In this phase, purposive sampling and in-depth individual interviews will be conducted for data collection. The conventional content analysis approach will be employed for data analysis. In addition to literature review and nominal group technique, the findings of the qualitative and quantitative phases, will be used to recommend some strategies to support adolescent pregnant women to improve their health practices during pregnancy.

Discussion

This is the first study looking into health practices in adolescent pregnant women which will be performed via a mixed-method approach, aiming to develop health practices improvement strategies. It is worth noting that there is no strategic guideline in Iran’s health system for improvement of health practices of adolescents. Therefore, it is hoped that the strategy proposed in the current study can enhance health practices of adolescents during pregnancy and ultimately improve their pregnancy and childbirth outcomes.

Ethical code

IR.TBZMED.REC.1397.670.

Origins in the Womb: Potential Role of the Physical Therapist in Modulating the Deleterious Effects of Obesity on Maternal and Offspring Health Through Movement Promotion and Prescription During Pregnancy

Maternal obesity and associated metabolic disease contribute to adverse outcomes in women and their offspring, and many of these outcomes have significant acute and chronic implications for both mother and neonate. Targeted movement (ie, physical activity or exercise training) during pregnancy has been shown to be safe and effective for improving many of these outcomes in women at a healthy weight and women who are obese. However, movement prescription and advice during pregnancy are often not addressed by health care providers; this situation creates a unique opportunity for physical therapists to use their expertise in movement with patients who are pregnant. The objective of this article is to briefly review the adverse maternal and neonatal outcomes associated with maternal obesity, the benefits of intentional maternal movement during pregnancy for women who are obese, the evidence-based guidelines for prescribing intentional movement during pregnancy for women who are obese, and the potential for physical therapists to become the driving force behind a necessary increase in movement levels in women who are pregnant. Physical therapists can play a significant role in encouraging movement in women who are healthy and women who have metabolic challenges during pregnancy and thus assist in combating the vicious cycle of obesity by improving maternal and offspring health.

The influence of physical activity during pregnancy on maternal, fetal or infant heart rate variability: a systematic review

Background

Physical activity (PA) during pregnancy has been shown to be associated with several positive effects for mother, fetus, and offspring. Heart rate variability (HRV) is a noninvasive and surrogate marker to determine fetal overall health and the development of fetal autonomic nervous system. In addition, it has been shown to be significantly influenced by maternal behavior. However, the influence of maternal PA on HRV has not yet been systematically reviewed. Therefore, the aim of this systematic review was to assess the influence of regular maternal PA on maternal, fetal or infant HRV.

Methods

A systematic literature search following a priori formulated criteria of studies that examined the influence of regular maternal PA (assessed for a minimum period of 6 weeks) on maternal, fetal or infant HRV was performed in the databases Pubmed and SPORTDiscus. Quality of each study was assessed using the standardized Quality Assessment Tool for Quantitative Studies (QATQS).

Results

Nine articles were included into the present systematic review: two intervention studies, one prospective longitudinal study, and six post-hoc analysis of subsets of the longitudinal study. Of these articles four referred to maternal HRV, five to fetal HRV, and one to infant HRV. The overall global rating for the standardized quality assessment of the articles was moderate to weak. The articles regarding the influence of maternal PA on maternal HRV indicated contrary results. Five of five articles regarding the influence of maternal PA on fetal HRV showed increases of fetal HRV on most parameters depending on maternal PA. The article referring to infant HRV (measured one month postnatal) showed an increased HRV.

Conclusions

Based on the current evidence available, our overall conclusion is that the hypothesis that maternal PA influences maternal HRV cannot be supported, but there is a trend that maternal PA might increase fetal and infant HRV (clinical conclusion). Therefore, we recommend that further, high quality studies addressing the influence of maternal PA on HRV should be performed (methodological conclusion).

Influence of physical exercise on baroreceptor sensitivity during pregnancy

BACKGROUND

Baroreceptor sensitivity (BRS) refers to the magnitude of change in the heart rate in response to change in blood pressure (e.g. upon standing). The impact of regular antenatal exercise on maternal BRS is unclear.

AIMS

To determine whether supervised weekly exercise influences BRS, and to determine if posture and calculation method are important in antenatal BRS measurement.

STUDY DESIGN AND SUBJECTS

Eighty-one healthy pregnant women were randomly assigned to an exercise or control group. The exercise group attended weekly classes from the 20th week of pregnancy onwards.

OUTCOME MEASURES

Cardiovascular assessments (beat-to-beat blood pressure, heart rate) were performed at 12-16, 26-28, 34-36 weeks and 12 weeks following birth. BRS was calculated using two methods ("sequence" and "beat-to-beat").

RESULTS

Fifty-one women (63%) completed the study. Mean BRS reduced progressively in all women (p < 0.025) and was lowest in those who exercised (0.046 < p < 0.002). Postnatal increases in BRS were independent of posture. Training-induced BRS (beat-to-beat) reduction occurred earlier than BRS (sequence), and only BRS (sequence) was affected by posture. Heart rate variability reduced with advancing gestation (p < 0.002) and was more pronounced in the exercise group (p < 0.029).

CONCLUSIONS

Weekly exercise exaggerated the reductions in BRS and HRV during pregnancy and is likely linked to diminished parasympathetic activity.

Differences in autonomic neural activity during exercise between the second and third trimesters of pregnancy

AIM

To test the hypothesis that autonomic neural activity in pregnant women during exercise varies according to gestational age.

METHODS

This cross-sectional study involved 20 healthy women in their second (n = 13) or third (n = 7) trimester of pregnancy. Incremental cardiopulmonary exercise testing was performed with an electromagnetic cycle ergometer. Heart rate variability was analyzed by frequency analysis software.

RESULTS

The low-frequency to high-frequency (LF/HF) ratio, an indicator of the sympathetic nervous system, was significantly higher in third trimester than in second trimester subjects (P < 0.05) at 1, 2, and 3 min of incremental exercise testing. In contrast, the HF/total power ratio, an indicator of rapidly acting parasympathetic activity, was significantly higher in second trimester than in third trimester subjects (P < 0.05) at 2 and 3 min. In addition, a negative correlation was found between gestational age and the 'accumulation half-time' of the LH/HF ratio, the time point at which the sum of the LF/HF ratio reached 50% of that accumulated in the total 6 min of exercise testing (r = -0.49, P = 0.028).

CONCLUSIONS

The autonomic response to exercise in pregnant women differs between the second and third trimesters. These differences should be considered when prescribing exercise to pregnant women.

Cardiac Physiology of Pregnancy

Although the physiology of the heart and vascular system has not changed, there are many things we have learned and are still learning today. Research related to heart adaptations during pregnancy has been performed since the 1930s. Since the mid-1950s, researchers began to look at changes in the maternal cardiovascular system during exercise while pregnant. Research related to exercise during pregnancy and offspring heart development began and has continued since the 1970s. We will review the normal female cardiovascular system adaptations to pregnancy in general. Additionally, topics related to maternal cardiac adaptations to pregnancy during acute exercise, as well as the chronic conditioning response from exercise training will be explored. Since physical activity during pregnancy influences fetal development, the fetal cardiac development will be discussed in regards to acute and chronic maternal exercise. Similarly, the influence of various types of maternal exercise on acute and chronic fetal heart responses will be described. Briefly, the topics related to how and if there is maternal-fetal synchrony will be explained. Lastly, the developmental changes of the fetal cardiovascular system that persist after birth will be explored. Overall, the article will discuss maternal cardiac physiology related to changes with normal pregnancy, and exercise during pregnancy, as well as fetal cardiac physiology related to changes with normal development, and exercise during pregnancy as well as developmental changes in offspring after birth.

Influence of antenatal physical exercise on heart rate variability and QT variability

OBJECTIVE

We sought to characterise the influence of an antenatal exercise programme on ECG-derived cardiac variables.

METHODS

Fifity-one healthy pregnant women were recruited and randomly assigned (2 × 2×2 design) to an exercise group or a control group. Exercising groups attended weekly classes from the 20th week of pregnancy onwards. Cardiovascular assessments (heart rate variabiliy (HRV), QT, and the QT variability index (QTVI)) were performed at 12-16, 26-28, 34-36 weeks and 12 weeks following birth, during supine rest and exercise conditions.

RESULTS

Advancing gestation was associated with an increased maternal heart rate (p = 0.001), shorter QT interval (p = 0.003), diminished HRV (p = 0.002) and increased QTVI (p = 0.002). Each of these changes was reversed within 12 weeks postpartum (p < 0.004). The Exercise group displayed exaggerated changes for all variables (except QT) but only during supine rest in the third trimester (p < 0.029).

CONCLUSION

Advancing gestation is associated with a shift in HRV/QTVI towards values that have been associated with an elevated risk of arrhythmia. A 20-week exercise programme undertaken between mid and late pregnancy exaggerated these changes during rest in the third trimester of pregnancy.

Influence of antenatal physical exercise on haemodynamics in pregnant women: a flexible randomisation approach

Background

Normal pregnancy is associated with marked changes in haemodynamic function, however the influence and potential benefits of antenatal physical exercise at different stages of pregnancy and postpartum remain unclear. The aim of this study was therefore to characterise the influence of regular physical exercise on haemodynamic variables at different stages of pregnancy and also in the postpartum period.

Methods

Fifity healthy pregnant women were recruited and randomly assigned (2 × 2 × 2 design) to a land or water-based exercise group or a control group. Exercising groups attended weekly classes from the 20th week of pregnancy onwards. Haemodynamic assessments (heart rate, cardiac output, stroke volume, total peripheral resistance, systolic and diastolic blood pressure and end diastolic index) were performed using the Task Force haemodynamic monitor at 12–16, 26–28, 34–36 and 12 weeks following birth, during a protocol including postural manoeurvres (supine and standing) and light exercise.

Results

In response to an acute bout of exercise in the postpartum period, stroke volume and end diastolic index were greater in the exercise group than the non-exercising control group (p = 0.041 and p = 0.028 respectively). Total peripheral resistance and diastolic blood pressure were also lower (p = 0.015 and p = 0.007, respectively) in the exercise group. Diastolic blood pressure was lower in the exercise group during the second trimester (p = 0.030).

Conclusions

Antenatal exercise does not appear to substantially alter maternal physiology with advancing gestation, speculating that the already vast changes in maternal physiology mask the influences of antenatal exercise, however it does appear to result in an improvement in a woman’s haemodynamic function (enhanced ventricular ejection performance and reduced blood pressure) following the end of pregnancy.

Trial registration

ClinicalTrials.gov NCT02503995. Registered 20 July 2015.

Diet or exercise, or both, for preventing excessive weight gain in pregnancy

BACKGROUND

This is an update of a Cochrane review first published in 2012, Issue 4. Excessive weight gain during pregnancy is associated with poor maternal and neonatal outcomes including gestational diabetes, hypertension, caesarean section, macrosomia, and stillbirth. Diet or exercise interventions, or both, may reduce excessive gestational weight gain (GWG) and associated poor outcomes; however, evidence from the original review was inconclusive.

OBJECTIVES

To evaluate the effectiveness of diet or exercise, or both, interventions for preventing excessive weight gain during pregnancy and associated pregnancy complications.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (5 November 2014), contacted investigators of the previously identified ongoing studies and scanned reference lists of retrieved studies.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of diet or exercise, or both, interventions for preventing excessive weight gain in pregnancy.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and risk of bias, extracted data and checked them for accuracy. We organised RCTs according to the type of interventions and pooled data using the random-effects model in the Review Manager software. We also performed subgroup analyses according to the initial risk of adverse effects related to poor weight control. We performed sensitivity analysis to assess the robustness of the findings.

MAIN RESULTS

We included 65 RCTs, out of which 49 RCTs involving 11,444 women contributed data to quantitative meta-analysis. Twenty studies were at moderate-to-high risk of bias. Study interventions involved mainly diet only, exercise only, and combined diet and exercise interventions, usually compared with standard care. Study methods varied widely; therefore, we estimated the average effect across studies and performed sensitivity analysis, where appropriate, by excluding outliers and studies at high risk of bias.Diet or exercise, or both, interventions reduced the risk of excessive GWG on average by 20% overall (average risk ratio (RR) 0.80, 95% confidence interval (CI) 0.73 to 0.87; participants = 7096; studies = 24; I² = 52%). This estimate was robust to sensitivity analysis, which reduced heterogeneity, therefore we graded this evidence as high-quality. Interventions involving low glycaemic load diets, supervised or unsupervised exercise only, or diet and exercise combined all led to similar reductions in the number of women gaining excessive weight in pregnancy.Women receiving diet or exercise, or both interventions were more likely to experience low GWG than those in control groups (average RR 1.14, 95% CI 1.02 to 1.27; participants = 4422; studies = 11; I² = 3%; moderate-quality evidence). We found no difference between intervention and control groups with regard to pre-eclampsia (RR 0.95, 95% CI 0.77 to 1.16; participants = 5330; studies = 15; I² = 0%; high-quality evidence); however, maternal hypertension (not a pre-specified outcome) was reduced in the intervention group compared with the control group overall (average RR 0.70, 95% CI 0.51 to 0.96; participants = 5162; studies = 11; I² = 43%; low-quality evidence).There was no clear difference between groups with regard to caesarean delivery overall (RR 0.95, 95% CI 0.88 to 1.03; participants = 7534; studies = 28; I² = 9%; high-quality evidence); although the effect estimate suggested a small difference (5%) in favour of the interventions. In addition, for combined diet and exercise counselling interventions there was a 13% (-1% to 25%) reduction in this outcome (borderline statistical significance).We found no difference between groups with regard to preterm birth overall (average RR 0.91, 95% CI 0.68 to 1.22; participants = 5923; studies = 16; I² = 16%; moderate-quality evidence); however limited evidence suggested that these effect estimates may differ according to the types of interventions, with a trend towards an increased risk for exercise-only interventions.We found no clear difference between intervention and control groups with regard to infant macrosomia (average RR 0.93, 95% CI 0.86 to 1.02; participants = 8598; studies = 27; I² = 0%; high-quality evidence), although the effect estimate suggested a small difference (7% reduction) in favour of the intervention group. The largest effect size occurred in the supervised exercise-only intervention group (RR 0.81, 95% CI 0.64 to 1.02; participants = 2445; studies = 7; I² = 0%), which approached statistical significance (P = 0.07). Furthermore, in subgroup analysis by risk, high-risk women (overweight or obese women, or women with or at risk of gestational diabetes) receiving combined diet and exercise counselling interventions experienced a 15% reduced risk of infant macrosomia (average RR 0.85, 95% CI 0.73 to 1.00; participants = 3252; studies = nine; I² = 0; P = 0.05; moderate-quality evidence)There were no differences in the risk of poor neonatal outcomes including shoulder dystocia, neonatal hypoglycaemia, hyperbilirubinaemia, or birth trauma (all moderate-quality evidence) between intervention and control groups; however, infants of high-risk women had a reduced risk of respiratory distress syndrome if their mothers were in the intervention group (RR 0.47, 95% CI 0.26 to 0.85; participants = 2256; studies = two; I² = 0%; moderate-quality evidence).

AUTHORS' CONCLUSIONS

High-quality evidence indicates that diet or exercise, or both, during pregnancy can reduce the risk of excessive GWG. Other benefits may include a lower risk of caesarean delivery, macrosomia, and neonatal respiratory morbidity, particularly for high-risk women receiving combined diet and exercise interventions. Maternal hypertension may also be reduced. Exercise appears to be an important part of controlling weight gain in pregnancy and more research is needed to establish safe guidelines. Most included studies were carried out in developed countries and it is not clear whether these results are widely applicable to lower income settings.

Physical activity during pregnancy and the risk of gestational diabetes mellitus: a systematic review and meta-analysis of randomised controlled trials

OBJECTIVES

We performed a systematic review and meta-analysis to assess the effects of physical activity in preventing gestational diabetes mellitus (GDM).

SEARCH STRATEGY

We searched the literature in six electronic databases and bibliographies of relevant articles.

SELECTION CRITERIA

We included randomised controlled trials on pregnant women who did not have GDM and other complications previously and had increased physical activity as the only intervention. The risk of developing GDM was documented separately for the intervention and control groups.

DATA COLLECTION AND ANALYSIS

Two reviewers extracted data and assessed quality independently. Data from the included trials were combined using a fixed-effects model. The effect size was expressed as relative risk (RR) and 95% CI.

MAIN RESULTS

Of the 1110 studies identified, six randomised controlled trials met the inclusion criteria. In three trials, the incidence of GDM was lower in the intervention group than in the control group, whereas two trials showed a higher incidence of GDM in the intervention group and the remaining trial found no GDM in either the intervention or control group. The meta-analysis resulted in a relative risk (RR) of GDM of 0.91 (95% CI 0.57 to 1.44), suggesting no significant difference in the risk of developing GDM between the intervention and the control groups. No indication of publication bias was found.

CONCLUSIONS

Evidence was insufficient to suggest that physical activity during pregnancy might be effective to lower the risk of developing GDM.

Relationship Between Maternal Fetal Attachment and State Anxiety of Pregnant Women in the Preterm Labor

PURPOSE

The Purpose of this study was to investigate relationships between maternal fetal attachment and state anxiety for pregnant women in preterm labor.

METHODS

The subjects consisted of 56 pregnant women in preterm labor on C hospital. The data were analyzed using SPSS computer program that includes descriptive statistics, mean, standard deviation, t-test, ANOVA, Scheffe? test and Pearson correlation coefficient.

RESULTS

Age distribution was 30~39 years of age. Mean score of maternal fetal attachment was 91.50. The group whose planned pregnancy was highest showed higher maternal fetal attachment. The primigravida group showed high maternal fetal attachment. Most frequently practiced attachment item was: "I'm really looking forward to seeing what the baby looks like". The next was was: "I enjoy watching my tummy jiggle as the baby kicks inside". There was no difference in degree of anxiety by general and obstetrical characteristics. There was statistically significant of negative correlation between maternal fetal attachment and state anxiety for pregnant women with preterm labor.

CONCLUSION

Findings provide useful information for further studies in reducing anxiety and intervention programs relating to pregnancy and preterm labor. To increase maternal fetal attachment of pregnant women with preterm labor, it is necessary to standardize prenatal education program.

Exercise in obese pregnant women: positive impacts and current perceptions

Overweight and obesity have significant implications during pregnancy and childbirth. The objective of this review was to provide a comprehensive overview of the effect of physical activity on pregnancy outcomes, the change of physical activity during pregnancy, and women's perception of being physically active during pregnancy, with a particular focus on women who are overweight or obese. Many studies have investigated the beneficial effect of exercise during pregnancy, including reduced risk of gestational diabetes, preeclampsia, and operative birth, in addition to improved cardiovascular function, overall fitness, psychological well-being, and mood stability. Benefits for the infant include reduced risks of prematurity and improved fetal growth, although there is more limited information about longer-term health benefits for both women and infants. The existing literature examining physical activity patterns during pregnancy has generally focused on women of all body mass index categories, consistently indicating a reduction in activity over the course of pregnancy. However, the available literature evaluating physical activity during pregnancy among women who are overweight or obese is more limited and contradictory. A number of studies identified barriers preventing women from being active during pregnancy, including pregnancy symptoms, lack of time, access to child care, and concerns about their safety and that of their unborn baby. Conversely, significant enablers included positive psychological feelings, family influence, and receiving advice from health professionals. Very few studies have provided insights about perceptions of being active during pregnancy in the overweight and obese population. There is a need for a detailed description of physical activity patterns during pregnancy in women who are overweight or obese, and more randomized trials evaluating exercise interventions for women who are overweight or obese, with a focus on clinical outcomes.

Exercise and physical activity in the prevention of pre-eclampsia: systematic review

Exercise and physical activity have been studied and suggested as a way to reduce or minimize the effects of pre-eclampsia. Our aim was to evaluate the association between exercise and/or physical activity and occurrence of pre-eclampsia. We conducted electronic searches without year of publication and language limitations. This was a systematic review designed according to PRISMA. Different databases accessed were as follows: PubMed®; Latin-American and Caribbean Literature in Health Sciences (LILACS); Scientific Electronic Library On-line (SciELO); Physiotherapy Evidence Database (PEDro); and ISI web of Knowledge(SM) . The Medical Subject Headings (MeSH) were as follows: ("exercise" OR "motor activity" OR "physical activity") AND ("pre-eclampsia" OR "eclampsia" OR "hypertension, pregnancy-induced"). Inclusion criteria were studies conducted in adults who were engaged in some physical activity. The selection and methodological evaluation were carried out by two independent reviewers. Risk assessment was made by the odds ratio (OR) and incidence of pre-eclampsia in the population who performed physical activity/exercise. A total of 231 articles were found, 214 of which were excluded based on title and full-text, so that 17 remained. Comparison of six case-control studies showed that physical activity had a protective effect on the development of pre-eclampsia [OR 0.77, 95% confidence interval (CI) 0.64-0.91, p < 0.01]. The 10 prospective cohort studies showed no significant difference (OR 0.99, 95% CI 0.93-1.05, p= 0.81). The only randomized clinical trial showed a protective effect on the development of pre-eclampsia in the stretching group (OR 6.34, 95% CI 0.72-55.37, p= 0.09). This systematic review indicates a trend toward a protective effect of physical activity in the prevention of pre-eclampsia.

Effects of aerobic exercise training on variability and heart rate kinetic during submaximal exercise after gastric bypass surgery--a randomized controlled trial

BACKGROUND

This study aimed to determine whether morbidly obese women have an alteration of heart rate (HR) kinetics and HR variability (HRV) during the 6-min walk test (6MWT) and if an aerobic exercise training can modify these indexes after gastric bypass surgery (GBS).

DESIGN AND METHODS

Nineteen morbidly obese women were randomized to a trained (TG) or control group and 12 women of eutrophic group (EG) were also evaluated. The obese women were tested on two occasions: 1 week before and 4 months after GBS through record of HR and R-R intervals during 6MWT for analysis HR kinetics. The TG underwent an aerobic exercise training program on a treadmill (1-h session, totaling 36 sessions over 12-week).

RESULTS

Both obese groups demonstrated a significant reduction of rMSSD and slower HR kinetics during the 6MWT when compared to the EG. In addition, only the TG demonstrated a significant improvement in HRV indexes, walking distance, faster time constant and mean response time of HR during 6MWT after training (p < 0.05).

CONCLUSION

Morbidly obese women have slower HR kinetics and altered cardiac modulation during submaximal exercise. However, aerobic exercise training can produce beneficial adaptations in HRV and faster HR kinetics following GBS.

The influence of maternal-fetal attachment and health practices on neonatal outcomes in low-income, urban women

Maternal-fetal attachment (MFA) has been associated with health practices during pregnancy, but less is known about this relationship in low-income women, and no identified studies have examined this relationship to neonatal outcomes. This longitudinal descriptive study was conducted to examine the relationships among MFA, health practices during pregnancy, and neonatal outcomes in a sample of low-income, predominantly African-American women and their neonates. MFA was associated with health practices during pregnancy and adverse neonatal outcomes. Health practices during pregnancy mediated the relationships of MFA and adverse neonatal outcomes. The results support the importance of examining MFA in our efforts to better understand the etiology of health disparities in neonatal outcomes.

Improving pregnancy outcome in obese women

The global pandemic of maternal obesity presents a major challenge for healthcare providers, and has significant short- and long-term implications for both maternal and fetal health. Currently, the evidence-base underpinning many of the interventions either currently in use or recommended to improve pregnancy outcome in obese women is limited. The nature and timing of these interventions vary widely, ranging from simple advice to more intensive dietary and exercise programmes, cognitive behavioural therapy and drug trials. In addition, a growing number of very severely obese women now enter pregnancy having had surgical interventions. Although surgical interventions such as gastric bypass or banding may be associated with improved pregnancy outcomes, these women have particular nutritional requirements, which need to be addressed to optimise pregnancy outcome. Until the outcomes of ongoing current trials are reported and provide a firm evidence base on which to base future intervention strategies and guide evidence based care for obese pregnant women, pregnancy outcome is best optimised by high-risk antenatal care delivered by healthcare providers who are experienced in supporting these high-risk women.

DNA damage and health in pregnancy

In healthy pregnancy reactive oxygen species and antioxidants remain in balance and DNA damage is repaired effectively. However, pregnancy is an inflammatory state exhibiting increased susceptibility to oxidative stress such that this balance can be easily disrupted. Increased DNA damage has been shown to be involved in many pathological states including pregnancy complications. Modern lifestyles including exposure to pollutants, poor diet, and lack of exercise cause excess inflammation, oxidative stress, and ultimately DNA damage. There is a growing body of literature providing evidence that these lifestyle changes are increasing our risk of infertility, miscarriage, and late-gestation pregnancy complications. Moreover, baseline DNA damage rises with age and couples in developed societies are delaying childbirth, placing them at further risk. In order to understand the effect of lifestyle and DNA damage on pregnancy health we require large prospective studies, with the collection of samples prior to conception and endpoints of time-to-pregnancy, early pregnancy loss, and late-gestation maternal and fetal health.