The effect of yoga on birth outcomes of Chinese pregnancies with preeclampsia

Abstract

Objective

This study aimed to assess the association between prenatal yoga intervention and birth outcomes in Chinese pregnancies complicated by preeclampsia (PE). Specifically, it evaluated the relationship between yoga and neonatal outcomes such as Apgar scores, preterm birth, and low birth weight, as well as maternal hospitalization duration.

Methods

A prospective, non-randomized interventional study was conducted. A total of 136 pregnant women diagnosed with mild preeclampsia were enrolled at Qingdao Municipal Hospital between February 2025 and May 2025. The cohort primarily consisted of early-onset preeclampsia cases, with an overall mean gestational age at birth of 37.36 ± 2.01 weeks. Participants were allocated into two groups: the PE group (n = 82) and the PE + Yoga group (n = 54). The PE group received standard obstetric care, while the PE + Yoga group participated in a structured prenatal yoga program three times per week, starting at gestational weeks 28–32. Clinical data were collected, including maternal baseline characteristics, pregnancy-related factors, and birth outcomes. Neonatal parameters such as birth weight, length, and circumferences of the head and chest were recorded. Logistic regression analysis was used to evaluate the association between yoga and birth outcomes.

Results

Significant improvements were associated with the PE + Yoga group compared to the PE group. Neonates in the PE + Yoga group had significantly higher birth weight (2.59 ± 0.21 kg vs. 2.21 ± 0.26 kg, P < 0.001), greater birth length (49.41 ± 1.88 cm vs. 43.83 ± 2.20 cm, P < 0.001), and larger head and chest circumferences (P < 0.001 for both). The PE + Yoga group also showed a significantly lower incidence of low 5-minute Apgar scores (7.41% vs. 26.83%, P = 0.007), preterm birth (24.07% vs. 48.78%, P = 0.004), and low birth weight (27.78% vs. 59.76%, P < 0.001). Logistic regression analysis further indicated that yoga was associated with a significantly lower risk of low 5-minute Apgar scores (OR = 0.218, P = 0.008), preterm birth (OR = 0.333, P = 0.005), and low birth weight (OR = 0.259, P < 0.001). Additionally, maternal hospitalization duration was significantly shorter in the PE + Yoga group (8.44 ± 2.85 days vs. 10.17 ± 2.84 days, P = 0.001).

Conclusion

Prenatal yoga intervention was associated with significant improvements in neonatal and maternal outcomes in pregnancies complicated by preeclampsia. The findings suggest that yoga is linked to better fetal growth, a lower risk of preterm birth, and a decrease in maternal hospitalization duration, highlighting its potential role as an adjunct therapy in managing preeclampsia.

Background

Preeclampsia (PE) represents a prevalent and serious hypertensive complication during pregnancy, significantly influencing both maternal and neonatal health outcomes, with notable associations with increased risks of morbidity and mortality on a global scale [1, 2]. Preeclampsia, typically emerging after 20 weeks of pregnancy, is identified by newly developed hypertension alongside proteinuria or signs of dysfunction in vital organs. Affecting an estimated 2–8% of pregnancies worldwide, its occurrence appears notably higher in certain regions, particularly among Asian populations such as those in China [3]. Despite advances in prenatal care, the management of preeclampsia remains challenging, as its pathogenesis is complex and multifactorial, involving abnormal placentation, endothelial dysfunction, and maternal immune maladaptation [4, 5]. Notably, preeclampsia is linked to an increased likelihood of unfavorable birth outcomes, e.g., restricted fetal growth, preterm delivery, reduced birth weight, and, in severe cases, stillbirth [6–8].

Current clinical management strategies for preeclampsia primarily focus on blood pressure control, maternal-fetal monitoring, and timely delivery when indicated [3, 9]. However, there is growing interest in complementary interventions that may improve maternal well-being and optimize perinatal outcomes. Among these, prenatal yoga has gained increasing attention due to its potential benefits in promoting maternal relaxation [10], improving cardiovascular function [11], enhancing utero-placental perfusion [12], and reducing stress-related hormonal responses [13], all of which may have relevance in pregnancies complicated by hypertensive disorders.

Earlier research examining the impact of prenatal yoga has primarily concentrated on pregnant women without complications, highlighting potential benefits such as enhanced maternal well-being, lower levels of prenatal anxiety and depression, and a possible decrease in certain pregnancy-related complications [10, 11, 13, 14]. However, limited evidence exists regarding the impact of prenatal yoga specifically in high-risk pregnancies, such as those complicated by preeclampsia. Furthermore, data on the effect of yoga on neonatal outcomes in preeclamptic pregnancies, particularly in Chinese populations, remain scarce. Considering the high burden of adverse birth outcomes associated with preeclampsia and the increasing integration of complementary therapies into maternal care in China, it is essential to explore whether prenatal yoga could serve as a beneficial adjunctive intervention in this high-risk population.

Therefore, this study aimed to investigate the effect of a structured prenatal yoga program on birth outcomes among Chinese women with mild preeclampsia. By evaluating key neonatal parameters—including birth weight, birth length, head and chest circumference, as well as rates of low 5-minute Apgar score, preterm birth, and low birth weight—this study sought to provide evidence for the potential role of prenatal yoga in improving perinatal outcomes in pregnancies complicated by preeclampsia. Findings from this research are expected to contribute to the development of evidence-based guidelines for complementary care in high-risk pregnancies and provide practical insights into the integration of prenatal yoga into routine obstetric care for women with preeclampsia.

Methods

Study design and participants enrollment

This research was carried out as a prospective, non-randomized interventional study at Qingdao Municipal Hospital between February 2025 and May 2025, following approval from the Ethics Committee of Qingdao Municipal Hospital (No.: 2025-KY-019). Prior to participation, all enrolled individuals provided written informed consent. Pregnant women diagnosed with PE were identified and recruited during scheduled prenatal check-ups. The diagnosis adhered to the criteria set by the American College of Obstetricians and Gynecologists (ACOG) in the 2013 revision, characterized by newly developed hypertension—defined as systolic blood pressure reaching or exceeding 140 mmHg and/or diastolic blood pressure at or above 90 mmHg—manifesting after 20 weeks of pregnancy, along with either proteinuria (≥ 300 mg/24 h) or indications of maternal organ dysfunction.

In this prospective, non-randomized interventional study, a total of 136 eligible participants were enrolled and non-randomly allocated into two groups. Specifically, the assignment was determined based on their personal preference, clinical eligibility, and willingness to commit to the structured prenatal yoga program, which was deliberately chosen to reflect a real-world clinical scenario while strictly respecting patient autonomy. The PE group (n = 82) received standard obstetric care for preeclampsia, including regular blood pressure monitoring, routine prenatal check-ups, dietary counseling, and pharmacologic therapy when indicated. Crucially, when pharmacological intervention was required, participants in both the PE and PE + Yoga groups received identical, standardized, and guideline-compliant antihypertensive treatments. The clinical management regarding the initiation, choice of drug, dosage, and duration of antihypertensive medications was strictly protocol-driven and adhered to established clinical guidelines for all patients, thereby ensuring no systematic differences in medical therapy between the two groups. The PE+Yoga group (n = 54) received the same standard obstetric care combined with a structured prenatal yoga intervention.

Inclusion and exclusion criteria

Inclusion criteria: (1) Pregnancy with a single fetus; (2) Gestational age ranging from 28 to 36 weeks at the time of recruitment; (3) Diagnosis of mild preeclampsia, with no clinical indications of severe complications. Exclusion criteria: (1) Severe preeclampsia, identified by the presence of any of the following: marked hypertension (systolic blood pressure reaching ≥ 160 mmHg and/or diastolic blood pressure at or above 110 mmHg), thrombocytopenia (platelet count < 100,000/µL), significant hepatic dysfunction, progressive renal impairment, pulmonary edema, or newly developed neurological or visual symptoms; (2) Pre-existing chronic hypertension diagnosed before pregnancy; (3) Gestational diabetes mellitus requiring insulin management; (4) Diagnosed fetal structural anomalies or chromosomal disorders; (5) Obstetric conditions contraindicating physical activity, including placenta previa, placental abruption, or other complications; (6) Severe maternal systemic illness, such as notable cardiac, pulmonary, hepatic, or renal dysfunction; (7) Previous engagement in structured physical activity programs, including yoga, during the current pregnancy.

Clinical information collection

Comprehensive clinical data were collected at enrollment and during follow-up until delivery. Maternal baseline information, including age, height, pre-pregnancy weight, and BMI, was obtained through standardized medical record review and structured interviews. Pregnancy-related data such as mode of conception, and other pregnancy complications were also recorded. Indices associated with preeclampsia, such as systolic and diastolic blood pressure, protein levels in urine, and the gestational period at childbirth, were recorded. Additionally, hospitalization duration (in days) was documented as part of the clinical outcomes. Following birth, trained personnel assessed neonatal parameters, including weight, body length, and circumferences of the head and chest, by adhering to established measurement guidelines. These comprehensive anthropometric parameters were deliberately selected over birth weight alone to provide a multidimensional assessment of fetal growth dynamics in the context of preeclampsia-induced placental insufficiency. Specifically, birth length and head circumference are crucial for evaluating skeletal growth and potential brain-sparing effects, while chest circumference serves as a highly sensitive and validated surrogate marker for fetal lean body mass, internal organ development, and soft tissue accretion. All data were cross-checked against the hospital’s electronic medical records for accuracy. To minimize bias, data collectors were blinded to group allocation when recording neonatal measurements and Apgar scores.

Yoga intervention

Individuals enrolled in the PE+Yoga intervention participated in a structured prenatal yoga regimen specifically tailored for expectant mothers diagnosed with preeclampsia. This program, developed with a focus on maternal health, was facilitated by certified prenatal yoga professionals who had undergone training in maternal-fetal safety. Conducted under supervision, the sessions were scheduled three times weekly, with each session spanning approximately 60 min, beginning at gestational weeks 28 to 32 and extending through to childbirth. Consequently, to guarantee a sufficient therapeutic duration of the intervention prior to delivery, participants who were enrolled between gestational weeks 32 and 36 were exclusively allocated to the standard obstetric care group. The yoga program integrated gentle physical movements (asanas), controlled breathing techniques (pranayama), and structured relaxation practices, including meditation. Postures were designed to incorporate mild stretching, activation of pelvic floor muscles, and promotion of circulatory function while deliberately avoiding excessive intra-abdominal pressure and inverted positions. Breathing techniques prioritized slow, diaphragmatic respiration, aiming to enhance parasympathetic engagement and support optimal oxygen transfer between mother and fetus. Each session concluded with a guided relaxation component, intended to aid in reducing psychological stress and maternal anxiety. Sessions took place within a designated hospital-based prenatal exercise space, where maternal and fetal parameters—including maternal blood pressure, heart rate, and fetal heart rate—were systematically monitored before and after each session. Additionally, participants were provided with instructional materials to facilitate optional home-based practice; however, adherence to self-directed sessions was not formally recorded.

To ensure uniformity in patient care and to minimize potential performance and treatment bias, both the PE and PE + Yoga groups received identical standard obstetric care managed uniformly by the same designated obstetric team at Qingdao Municipal Hospital. All routine clinical management decisions were strictly standardized across both groups. Specifically, the initiation and adjustment of antihypertensive pharmacological treatments, the criteria for hospital admission, and the determination of the optimal timing for delivery were rigidly dictated by institutional clinical pathways based on the American College of Obstetricians and Gynecologists (ACOG) guidelines. By adhering strictly to these standardized protocols, the subjective discretion of individual clinicians was effectively mitigated, ensuring that any observed differences in maternal and neonatal outcomes could be more reliably attributed to the prenatal yoga intervention rather than variations in clinical management.

Birth outcomes

The principal neonatal outcomes evaluated in this study encompassed reduced 5-minute Apgar scores, premature delivery, and lower-than-average birth weight, representing fundamental parameters associated with neonatal status in pregnancies affected by preeclampsia. Importantly, as the study cohort was strictly limited to patients diagnosed with mild preeclampsia at baseline, all outcome measures were evaluated free from the confounding influence of severe disease categories. A diminished 5-minute Apgar score was specified as a reading below 7 at five minutes post-delivery, suggesting potential neonatal distress. Preterm birth was categorized as delivery taking place before the completion of 37 weeks of gestation. To ensure clinical accuracy and interpretability, preterm births were further systematically classified into spontaneous preterm birth and medically indicated (iatrogenic) preterm birth, accounting for the clinical rationale necessitating early delivery. Birth weight was classified as low when recorded below 2500 g, aligning with the established thresholds outlined by the World Health Organization (WHO). Furthermore, to provide a precise reflection of placental function and fetal growth dynamics, instances of low birth weight were explicitly distinguished between those resulting solely from prematurity and those driven by fetal growth restriction (FGR) or being small for gestational age (SGA).

All birth-related outcomes were meticulously documented for each participant following delivery, utilizing clinical records maintained by obstetric and neonatal care teams. Every newborn underwent a structured postnatal physical assessment conducted immediately upon birth by attending neonatologists, ensuring uniformity and reliability in outcome evaluation.

Statistical analysis

The statistical evaluation in this study was conducted utilizing SPSS software, version 26.0. Assessment of continuous variables involved testing for normality, with results presented either as mean ± standard deviation (SD) or median with interquartile range, contingent on data distribution. Comparisons between groups were carried out using independent sample t-tests when data followed a normal distribution, whereas the Mann-Whitney U test was applied for non-normally distributed data. Categorical variables were summarized as frequencies and corresponding percentages, with statistical differences assessed using either the chi-square test or Fisher’s exact test, depending on the expected cell counts. To explore the potential association between prenatal yoga participation and birth-related outcomes, logistic regression models were employed. All hypothesis tests were conducted with a two-tailed approach, and statistical significance was determined at P < 0.05.

Results

Baseline characteristics of the pregnancies with preeclampsia received or not received yoga intervention

The baseline characteristics of participants in the PE group and the pre-eclampsia with yoga intervention (PE + Yoga) group are summarized in Table 1. A total of 136 women with pre-eclampsia were enrolled, with 82 in the PE group and 54 in the PE + Yoga group. The mean age was 26.40 ± 2.85 years in the PE group and 26.65 ± 2.40 years in the PE + Yoga group (P = 0.601). Height and weight were similar between the two groups, with no significant differences in height (P = 0.176) and a marginal difference in weight (P = 0.066), with the PE + Yoga group being slightly heavier. The PE + Yoga group had a significantly higher BMI (25.59 ± 2.27 kg/m²) compared to the PE group (24.79 ± 1.51 kg/m²) (P = 0.015). Blood pressure (SBP and DBP) was similar between groups (SBP: P = 0.89, DBP: P = 0.614). Gestational age at enrollment was comparable (P = 0.632). The PE + Yoga group had a significantly shorter hospitalization duration (8.44 ± 2.85 days) compared to the PE group (10.17 ± 2.84 days) (P = 0.001). Delivery mode was largely cesarean in both groups, with no significant difference (P = 0.741). Crucially, throughout the continuous clinical follow-up period from enrollment to delivery, no participants in either the PE group or the PE + Yoga group progressed to severe preeclampsia.

Table 1.

Baseline characteristics of the pregnancy with pre-eclampsia received or not received yoga treatment

Clinical indices	PE group (n = 82)	PE + Yoga group (n = 54)	P
Age (yrs)	26.40 ± 2.85	26.65 ± 2.40	0.601
Height (cm)	162.00 ± 3.87	160.81 ± 6.29	0.176
Weight (kg)	64.96 ± 2.68	65.89 ± 3.16	0.066
BMI (kg/m2)	24.79 ± 1.51	25.59 ± 2.27	0.015
SBP (mmHg)	142.85 ± 1.46	142.89 ± 1.45	0.89
DBP (mmHg)	92.96 ± 2.10	93.15 ± 2.06	0.614
Gestation (Weeks)	36.93 ± 1.33	36.81 ± 1.33	0.632
Hospitalization duration (day)	10.17 ± 2.84	8.44 ± 2.85	0.001
Type of delivery [n(%)]			0.741
Normal	5 (6.10)	4 (7.41)
C-section	77 (93.90)	50 (92.59)

Continuous variables are presented as mean ± standard deviation (SD) and were compared using the independent t-test. Categorical variables are expressed as number (percentage) and were compared using the Chi-square test. Statistical significance was defined as P < 0.05

PE Preeclampsia, BMI Body Mass Index, SBP Systolic Blood Pressure, DBP Diastolic Blood Pressure, C-section Cesarean section

Comparison of the neonatal characteristics of the pregnancies with preeclampsia received or not received yoga intervention

The neonatal characteristics of newborns delivered by mothers with preeclampsia, with or without yoga intervention during pregnancy, are summarized in Table 2. Significant differences were observed between the PE group and the PE + Yoga group across multiple neonatal parameters. The mean birth weight of newborns in the PE + Yoga group was significantly higher compared to those in the PE group (2.59 ± 0.21 kg vs. 2.21 ± 0.26 kg, P < 0.001), suggesting a potential beneficial effect of prenatal yoga on fetal growth in pregnancies complicated by preeclampsia. Similarly, newborns in the PE + Yoga group exhibited significantly greater birth length (49.41 ± 1.88 cm) compared to those in the PE group (43.83 ± 2.20 cm), with the difference being highly statistically significant (P < 0.001). In addition, head circumference was significantly larger in the PE + Yoga group, with a mean of 34.17 ± 1.15 cm, compared to 30.77 ± 1.80 cm in the PE group (P < 0.001). Furthermore, chest circumference was also significantly greater in the PE + Yoga group (32.17 ± 1.99 cm) than in the PE group (27.75 ± 2.01 cm), with a P value of < 0.001.

Table 2.

Neonatal characteristics of the newborns from the pregnancy with preeclampsia received or not received yoga treatment

Neonatal characteristics	PE group (n = 82)	PE + Yoga group (n = 54)	P value
Birth weight (kg)	2.21 ± 0.26	2.59 ± 0.21	< 0.001
Birth length (cm)	43.83 ± 2.20	49.41 ± 1.88	< 0.001
Head circumference (cm)	30.77 ± 1.80	34.17 ± 1.15	< 0.001
Chest circumference (cm)	27.75 ± 2.01	32.17 ± 1.99	< 0.001
Gestational age at birth (weeks)	37.12 ± 2.19	37.72 ± 1.68	0.09

All data are continuous variables presented as mean ± standard deviation (SD), and comparisons between the two groups were performed using the independent t-test. Statistical significance was defined as P < 0.05

PE preeclampsia

The comparison of birth outcomes of the pregnancies with pre-eclampsia received or not received yoga intervention

The comparison of birth outcomes between the PE group and the preeclampsia with yoga intervention (PE + Yoga) group is shown in Table 3. Significant differences were observed between the two groups across several key neonatal outcomes. The incidence of low 5-minute Apgar scores was significantly lower in the PE + Yoga group, with only 7.41% (4/54) of neonates having a score of ≤ 7, compared to 26.83% (22/82) in the PE group (P = 0.007). This suggests that yoga intervention during pregnancy may contribute to improved neonatal health immediately after birth. In terms of preterm birth, a significant reduction in the incidence was observed in the PE + Yoga group. Specifically, 24.07% (13/54) of the births in the PE + Yoga group were preterm, compared to 48.78% (40/82) in the PE group (P = 0.004). This indicates that prenatal yoga may help prolong gestation in women with preeclampsia, reducing the risk of preterm birth. The rate of low birth weight (defined as birth weight < 2500 g) was also significantly lower in the PE + Yoga group, with 27.78% (15/54) of neonates having low birth weight, compared to 59.76% (49/82) in the PE group (P < 0.001).

Table 3.

The comparison of birth outcomes of the pregnancy with pre-eclampsia received or not received yoga

Birth outcomes	PE group (n = 82)	PE + Yoga group (n = 54)	P value
Low 5 min Apgar score [n(%)]			0.007
Yes	22 (26.83)	4 (7.41)
No	60 (73.17)	50 (92.59)
Preterm birth [n(%)]			0.004
Yes	40 (48.78)	13 (24.07)
No	42 (51.22)	41 (75.93)
Low birth weight [n(%)]			< 0.001
Yes	49 (59.76)	15 (27.78)
No	33 (40.24)	39 (72.22)

Categorical variables are expressed as number (percentage) and were compared using the Chi-square test or Fisher's exact test, as appropriate. Statistical significance was defined as P < 0.05

PE preeclampsia

Logistic regression analysis of the effect of prenatal yoga on birth outcomes

To further explore the impact of prenatal yoga intervention on birth outcomes in pregnancies complicated by preeclampsia, logistic regression analysis was conducted (Table 4). The analysis revealed that prenatal yoga significantly influenced several critical birth outcomes. For the outcome of low 5-minute Apgar score, yoga intervention was found to significantly reduce the risk (ß = -1.522, SE = 0.576, Wald X² = 6.979, P = 0.008), with an OR of 0.218 (95% CI: 0.071–0.675). This suggests that prenatal yoga was associated with a 78% reduction in the odds of a low 5-minute Apgar score in preeclamptic pregnancies. Similarly, yoga intervention was significantly protective against preterm birth (ß = -1.100, SE = 0.387, Wald X² = 8.058, P = 0.005), with an OR of 0.333 (95% CI: 0.156–0.711). This finding indicates that yoga treatment during pregnancy reduced the odds of preterm birth by approximately 67%. Furthermore, yoga was found to significantly decrease the likelihood of low birth weight (ß = -1.351, SE = 0.378, Wald X² = 12.759, P < 0.001), with an OR of 0.259 (95% CI: 0.123–0.544). This suggests that prenatal yoga may lower the risk of low birth weight by approximately 74% in pregnancies complicated by preeclampsia.

Table 4.

The influencing effects of yoga treatment on the birth outcome in pregnancy with pre-eclampsia assessed by Logistic regression analysis

Birth outcomes	ß	SE	Wald X2	P	OR	95% CI
Low 5 min Apgar score	-1.522	0.576	6.979	0.008	0.218	0.071 ~ 0.675
Preterm birth	-1.1	0.387	8.058	0.005	0.333	0.156 ~ 0.711
Low birth weight	-1.351	0.378	12.759	< 0.001	0.259	0.123 ~ 0.544

Univariable logistic regression analysis was performed to evaluate the effect of the prenatal yoga intervention (independent variable) on specific birth outcomes (dependent variables). Statistical significance was defined as P < 0.05

SE Standard Error, OR Odds Ratio, CI Confidence Interval

Discussion

Preeclampsia (PE) is a significant contributor to adverse maternal and neonatal health outcomes, posing substantial risks to both mother and fetus. The condition is associated with considerable morbidity and mortality, with a notably high occurrence observed in China [15, 16]. Despite advances in prenatal care, effective interventions to improve outcomes remain limited due to PE’s complex pathogenesis. Prenatal yoga has shown benefits in healthy pregnancies, such as reducing stress [17] and improving cardiovascular function [18], but evidence in high-risk pregnancies, especially PE, is scarce. This study explored the potential influence of a structured prenatal yoga program on birth-related parameters in Chinese pregnant women diagnosed with mild preeclampsia. The results indicated that participation in prenatal yoga was linked to favorable changes in several neonatal indicators, e.g., head and chest circumference, length, and birth weight. Additionally, observed trends suggested a reduced likelihood of adverse outcomes, including low 5-minute Apgar scores, preterm delivery, and lower-than-average birth weight. These observations contribute to the growing body of knowledge regarding prenatal yoga as a potential complementary approach in the broader management of pregnancies affected by preeclampsia.

The current study found that neonates born to mothers in the prenatal yoga group exhibited significantly higher birth weight, greater birth length, and larger head and chest circumferences compared to those in the standard care group. These findings are consistent with emerging evidence indicating that prenatal yoga may have beneficial effects on fetal growth and development [19]. One possible explanation is that prenatal yoga may help enhance maternal cardiovascular function [11, 20] and potentially improves uteroplacental circulation [12], thereby contributing to fetal nutrient and oxygen supply. In addition, the relaxation and stress-reducing effects of yoga may help mitigate the adverse impact of maternal stress hormones, such as cortisol, which have been implicated in impaired fetal growth in preeclamptic pregnancies [21, 22].

Newborns delivered by mothers who participated in the yoga intervention exhibited a statistically significant reduced likelihood of having low 5-minute Apgar scores, a commonly used measure associated with neonatal adaptation challenges at birth. This finding may reflect the potential combined benefits of an improved intrauterine environment and enhanced maternal coping mechanisms during labor. Prenatal yoga is thought to reduce maternal anxiety and enhance maternal-fetal bonding, factors that could theoretically influence the labor process and neonatal adaptation to extrauterine life [14, 23]. Additionally, yoga-induced improvements in maternal respiratory efficiency might enhance maternal-fetal oxygen exchange, which is particularly critical in the context of preeclampsia-related placental insufficiency [24, 25].

The observed reduction in preterm birth rate in the yoga group is of particular clinical relevance, given the well-established association between preeclampsia and preterm delivery [26]. The potential mechanisms underlying this observed effect may include improved uterine tone and reduced uterine irritability resulting from regular yoga practice [27, 28]. Moreover, the possibility that yoga lowers maternal stress and inflammatory responses may help prolong gestation, especially in pregnancies predisposed to stress-induced preterm delivery [29, 30]. These findings align with prior research demonstrating that prenatal yoga is associated with lower rates of preterm birth in low-risk and high-risk pregnancies alike [31, 32]. Meanwhile, the significantly lower incidence of low birth weight in the yoga group further supports the potential role of prenatal yoga in supporting fetal growth in preeclamptic pregnancies. Low birth weight in preeclampsia is primarily attributable to uteroplacental insufficiency and fetal growth restriction [33]. Yoga may mitigate this process through multiple pathways, including reduced oxidative stress, and enhanced fetal nutrient delivery [34]. In addition, the stress-reducing effect of yoga might modulate the hypothalamic-pituitary-adrenal axis, potentially preventing excessive fetal exposure to maternal stress hormones that have been implicated in fetal growth restriction [35].

Yoga has emerged as a widely practiced complementary therapy during pregnancy, with increasing evidence supporting its possible beneficial effects on maternal physical and psychological health [35]. In uncomplicated pregnancies, engagement in prenatal yoga has been associated with increased maternal flexibility, relief from back discomfort, improved emotional well-being through reduced anxiety and depressive symptoms, and overall enhancement of quality of life during gestation [36, 37]. Importantly, emerging data suggest that yoga may also confer benefits in high-risk pregnancies, including those complicated by gestational hypertension, gestational diabetes, and preeclampsia [31]. However, existing studies in high-risk populations remain limited in scope and methodological quality, highlighting the need for well-designed, population-specific investigations, such as the present study, to further clarify the role of prenatal yoga in potentially optimizing pregnancy outcomes in high-risk settings.

An important consideration in interpreting our findings is the specificity of the observed benefits. Because our study design did not include an active control group engaging in general physical activity, it is difficult to completely disentangle the unique effects of yoga from the broader cardiovascular and metabolic advantages of regular exercise. While general physical activity is widely recognized for improving endothelial function and maternal hemodynamics, prenatal yoga is distinguished by its specific mind-body components, including controlled breathing techniques (pranayama) and meditation. These specific elements may provide targeted benefits for pregnancies complicated by preeclampsia, such as enhanced autonomic nervous system modulation and stress reduction. Nevertheless, to prevent over-interpretation, the intervention in this study should be cautiously viewed as a structured, low-impact exercise program enriched with mind-body techniques. Future trials employing active exercise comparators are warranted to ascertain whether the observed improvements in maternal-fetal outcomes are exclusively yoga-specific or predominantly driven by increased physical activity.

This study has several strengths, including its focus on a clinically meaningful population (Chinese patients with preeclampsia), use of a standardized prenatal yoga protocol tailored to preeclamptic pregnancies, and comprehensive assessment of neonatal outcomes using objective clinical measurements. The inclusion of a control group receiving standard care also enhances the validity of the observed associations. This study has several limitations. Firstly, the non-randomized design may introduce selection bias, as participants’ voluntary enrollment could reflect higher baseline health awareness. However, this preference-based allocation ensured ethical compliance and real-world feasibility while avoiding attrition common in forced randomization. Secondly, the limited sample size restricts generalizability and subgroup analyses. Third, untracked home practice may introduce intervention exposure variability. Fourth, the lack of systematic baseline clinical severity markers, such as specific blood pressure and protein levels, limits granular inter-group comparisons. Fifth, due to sample size constraints, we could not adjust for the observed baseline imbalance in maternal BMI. As BMI independently affects perinatal outcomes, this unadjusted confounder may influence the observed associations, warranting cautious interpretation of yoga’s independent effects. Finally, focusing on mild preeclampsia restricts applicability to severe cases. Future research should utilize larger, multicenter randomized trials with diverse populations and comprehensive clinical tracking. Further mechanistic studies are warranted to elucidate physiological pathways. Integrating yoga into tailored antenatal care packages could enhance intervention sustainability and accessibility in clinical practice.

In conclusion, this study contributes new insights suggesting that participation in a structured prenatal yoga program may be linked to favorable neonatal growth indicators and a reduced likelihood of certain adverse birth outcomes, such as lower Apgar scores, preterm delivery, and lower-than-average birth weight, among Chinese women diagnosed with mild preeclampsia. These observations highlight the potential role of prenatal yoga as a viable and accessible supportive intervention that may contribute to improved perinatal health in pregnancies affected by preeclampsia.

Abbreviations

PE

Preeclampsia

ACOG

American College of Obstetricians and Gynecologists

BMI

Body Mass Index

WHO

World Health Organization

FGR

Fetal Growth Restriction

SGA

Small for Gestational Age

SD

Standard Deviation

SBP

Systolic Blood Pressure

DBP

Diastolic Blood Pressure

OR

Odds Ratio

CI

Confidence Interval

SE

Standard Error

Authors’ contributions

All authors contributed significantly to this work and supported the publication of the manuscript. Xin Zhou and Dechun Liu: conceptualization. Xin Wang and Hong Fu: writing - original draft preparation. Xin Zhou and Dechun Liu: editing, and revising. Xin Zhou and Dechun Liu: supervision. Xin Wang and Hong Fu contributed equally to this work.

Funding

This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

Data availability

The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.

Declarations

Ethics approval and consent to participate

This study was approved by the Ethics Committee of Qingdao Municipal Hospital (Approval No.: 2025-KY-019) and was conducted in strict accordance with the ethical principles outlined in the Declaration of Helsinki and its later amendments. Written informed consent was obtained from all participants prior to enrollment.

Consent for publication

Not applicable.

Competing interests

The authors declare no competing interests.