Analysis of CTG patterns in cases with metabolic acidosis at birth with and without neonatal neurological alterations.

OBJECTIVE: To determine cardiotocographic patterns in newborns with metabolic acidosis, based on clinical signs of neurological alteration (NA) and the need for hypothermic treatment. METHODS: All term newborns with metabolic acidosis in a single center from 2016 to 2020 were included in the study. Three segments of intrapartum CTG (cardiotocography) were considered (first 30 min of active labor, 90 to 30 min before birth, and last 30 min before delivery) and a longitudinal analysis of CTG pattern was performed according to the 2015 FIGO classification. RESULTS: Three hundred and twenty-four neonates with metabolic acidosis diagnosed at birth were divided into three groups: the first group included all neonates with any clinical sign of neurological alteration, requiring hypothermia according to the recommendation of the Italian Society of Neonatology (group TNA-Treated neurological Alteration, n = 17), the second encompassed neonates with any clinical sign of neurological alteration not requiring hypothermia (group NTNA-Not Treated neurological Alteration, n = 83), and the third enclosed all neonates without any sign of clinical neurological involvement (group NoNA-No neurological Alteration, n = 224). The most frequent alterations of CTG in TNA group were late decelerations, reduced variability, bradycardia, and tachysystole. Unexpectedly, from the longitudinal analysis of the CTG, 49% of all cases with metabolic acidosis never showed a pathological CTG with normal trace at the beginning of labor followed by normal or suspicious trace in the final part of labor, the same as in TNA and NTNA groups (10 and 39%, respectively). CONCLUSIONS: CTG has limited specificity in identifying cases of acidosis at birth, even in babies who will develop NA.

Admission Cardiotocography and Neonatal Outcomes at a Tertiary Health Facility in Southwestern Nigeria.

BACKGROUND: Admission cardiotocography (CTG), a noninvasive procedure, is used to indicate the state of oxygenation of the fetus on admission into the labor ward. OBJECTIVE: This study assessed the association of admission CTG findings with neonatal outcome at a tertiary health facility. MATERIALS AND METHODS: A prospective, observational study of 206 pregnant women who were admitted into the labor ward with singleton live pregnancies. Information on the demographic characteristics, obstetrics and medical history, admission CTG tracing, and neonatal outcome was obtained using a structured data collection form. Data were analyzed using the SPSS software version 20.0 with the level of significance set at P < 0.05. RESULTS: The admission CTG findings were normal in 73.3%, suspicious in 13.6%, and pathological in 13.1% of the women. The occurrence of low birth weight, special care baby unit (SCBU) admission, asphyxiated neonates, neonatal death, and prolonged hospital admission was significantly more frequent among those with pathological admission CTG results compared with normal and suspicious results (P < 0.05). The incidence of vaginal delivery was more common when the CTG findings were normal, whereas all women with pathological CTG result had a cesarean delivery. CONCLUSION: Admission CTG was effective in identifying fetuses with a higher incidence of perinatal asphyxia. Neonatal outcome such as low birth weight, APGAR score, SCBU admission, and prolonged hospital admission was significantly associated with pathological CTG findings. In the absence of facilities for further investigations, prompt intervention for delivery should be ensured if admission CTG is pathological.

Résumé Contexte:La cardiotocographie d'admission (CTG), une procédure non invasive, est utilisée pour indiquer l'état d'oxygénation du fœtus lors de son admission en salle de travail.Objectif:Cette étude a évalué l'association entre les résultats du CTG à l'admission et l'issue néonatale dans un établissement de santé tertiaire.Matériels et méthodes:Une étude observationnelle prospective portant sur 206 femmes enceintes admises en salle de travail avec des grossesses vivantes uniques. Des informations sur les caractéristiques démographiques, les antécédents obstétricaux et médicaux, le traçage CTG à l'admission et les résultats néonatals ont été obtenues à l'aide d'un formulaire de collecte de données structuré. Les données ont été analysées à l'aide du logiciel SPSS version 20.0 avec le niveau de signification fixé à P <0,05.Résultats:Les résultats du CTG à l'admission étaient normaux chez 73,3 %, suspects chez 13,6 % et pathologiques chez 13,1 % des femmes. La survenue d'un faible poids à la naissance, d'une admission dans une unité de soins spéciaux pour bébés (SCBU), de nouveau-nés asphyxiés, de décès néonatals et d'une hospitalisation prolongée était significativement plus fréquente chez les personnes ayant des résultats CTG d'admission pathologiques par rapport aux résultats normaux et suspects (P < 0,05). L'incidence des accouchements par voie basse était plus fréquente lorsque les résultats du CTG étaient normaux, alors que toutes les femmes présentant un résultat pathologique du CTG avaient accouché par césarienne.Conclusion:L'admission CTG s'est avérée efficace pour identifier les fœtus présentant une incidence plus élevée d'asphyxie périnatale. Les résultats néonatals tels qu'un faible poids à la naissance, le score APGAR, l'admission au SCBU et l'hospitalisation prolongée étaient significativement associés aux résultats pathologiques du CTG. En l'absence de moyens permettant des investigations plus approfondies, une intervention rapide pour l'accouchement doit être assurée si l'admission du CTG est pathologique.

Rapid detection of fetal compromise using input length invariant deep learning on fetal heart rate signals.

Standard clinical practice to assess fetal well-being during labour utilises monitoring of the fetal heart rate (FHR) using cardiotocography. However, visual evaluation of FHR signals can result in subjective interpretations leading to inter and intra-observer disagreement. Therefore, recent studies have proposed deep-learning-based methods to interpret FHR signals and detect fetal compromise. These methods have typically focused on evaluating fixed-length FHR segments at the conclusion of labour, leaving little time for clinicians to intervene. In this study, we propose a novel FHR evaluation method using an input length invariant deep learning model (FHR-LINet) to progressively evaluate FHR as labour progresses and achieve rapid detection of fetal compromise. Using our FHR-LINet model, we obtained approximately 25% reduction in the time taken to detect fetal compromise compared to the state-of-the-art multimodal convolutional neural network while achieving 27.5%, 45.0%, 56.5% and 65.0% mean true positive rate at 5%, 10%, 15% and 20% false positive rate respectively. A diagnostic system based on our approach could potentially enable earlier intervention for fetal compromise and improve clinical outcomes.

Gestational buprenorphine-naloxone exposure and fetal neurobehavior.

BACKGROUND: Buprenorphine-naloxone treatment may confer substantial benefits for the treatment of opioid use disorder (OUD) during pregnancy including lower risk for overdose/death, less diversion potential and reduced use of other substances. Treatment may also result in less severe Neonatal Abstinence Syndrome (NAS), but little is known about the effects of this medication on fetal neurodevelopment. METHODS: The purpose of the current study is to evaluate neurobehaviors among fetuses exposed to buprenorphine-naloxone at four time points over the second and third trimesters of gestation in pregnant women with OUD on buprenorphine-naloxone therapy. Sixty minutes of continuous fetal monitoring via fetal actocardiograph with a single wide array abdominal transducer took place at times of peak and trough buprenorphine-naloxone levels in 24 pregnant women. Data collection, which included measures of fetal heart rate and motor activity, was conducted between 24 and 36 weeks gestation, with the majority (84.6%) monitored at two or more gestational ages. Medication dose and other substance use was monitored throughout the study and infant NAS severity was assessed. RESULTS: Fetal heart rate (FHR), FHR variability, accelerations in FHR, and motor activity were suppressed when buprenorphine-naloxone levels were at pharmacologic peak as compared to trough concentrations at 36 weeks, but not earlier in gestation. Maternal medication dose was unrelated to infant NAS severity. CONCLUSIONS: Conclusions: There were evident subclinical fetal neurophysiological responses at times of peak maternal buprenorphine/naloxone levels in later gestation, similar to those previously described for buprenorphine only. Further studies evaluating the effects of these changes in fetal neurobehaviors on the longer-term infant development are needed.

Fetal bradycardia in open versus fetoscopic prenatal repair of spina bifida.

OBJECTIVE: To compare the occurrence of fetal bradycardia in open versus fetoscopic fetal spina bifida surgery. METHODS: This is a single-institution retrospective cohort study of patients undergoing open (n = 25) or fetoscopic (n = 26) spina bifida repair between 2017 and 2022. From October 2017 to June 2020, spina bifida repairs were performed via an open classical hysterotomy, and from November 2020 to June 2022 fetoscopic repairs were performed following transition to this technique. Fetal heart rate (FHR) in beats per minute (bpm) was recorded via echocardiography every 15 min during the procedure. Cohort characteristics, fetal bradycardia and maternal physiologic parameters were compared between the groups. RESULTS: Fetuses undergoing an open repair more frequently developed bradycardia defined as <110 bpm (32% vs. 3.8%, p = 0.008), and a trend was observed for FHR decreases more than 25 bpm from baseline (20% vs. 3.8%, p = 0.073). Profound bradycardia less than 80 bpm was rare, occurring in only three operations (two in open, one in fetoscopic repair) with two fetuses (one in each group) requiring emergency cesarean delivery. CONCLUSION: When compared to open fetal surgery, fetal bradycardia occurred less frequently in fetoscopic surgery despite a significantly greater anesthetic exposure and the use of the intraamniotic carbon dioxide insufflation.

The benefit of active management in true knot of the umbilical cord: a retrospective study.

PURPOSE: To compare perinatal outcomes between active and routine management in true knot of the umbilical cord (TKUC). METHODS: A retrospective study of singletons born beyond 22 6/7 weeks with TKUC. Active management included weekly fetal heart rate monitoring(FHRM) ≥ 30 weeks and labor induction at 36-37 weeks. Outcomes in active and routine management were compared, including composite asphyxia-related adverse outcome, fetal death, labor induction, Cesarean section (CS) or Instrumental delivery due to non-reassuring fetal heart rate (NRFHR), Apgar5 score < 7, cord Ph < 7, neonatal intensive care unit (NICU) admission and more. RESULTS: The Active (n = 59) and Routine (n = 1091) Management groups demonstrated similar rates of composite asphyxia-related adverse outcome (16.9% vs 16.8%, p = 0.97). Active Management resulted in higher rates of labor induction < 37 weeks (22% vs 1.7%, p < 0.001), CS (37.3% vs 19.2%, p = 0.003) and NICU admissions (13.6% vs 3%, p < 0.001). Fetal death occurred exclusively in the Routine Management group (1.8% vs 0%, p = 0.6). CONCLUSION: Compared with routine management, weekly FHRM and labor induction between 36 and 37 weeks in TKUC do not appear to reduce neonatal asphyxia. In its current form, active management is associated with higher rates of CS, induced prematurity and NICU admissions. Labor induction before 37 weeks should be avoided.

Elicitation of fetal ECG from abdominal recordings using Blind Source Separation techniques and Robust Set Membership Affine Projection algorithm for signal quality enhancement.

BACKGROUND: The utilization of non-invasive techniques for fetal cardiac health surveillance is pivotal in evaluating fetal well-being throughout the gestational period. This process requires clean and interpretable fetal Electrocardiogram (fECG) signals. METHOD: The proposed work is the novel framework for the elicitation of fECG signals from abdominal ECG (aECG) recordings of the pregnant mother. The comprehensive approach encompasses pre-processing of the raw ECG signal, Blind Source Separation techniques (BSS), Decomposition techniques like Empirical Mode Decomposition (EMD), and its variants like Ensemble Empirical Mode Decomposition (EEMD), and Complete Ensemble Empirical Mode Decomposition with Additive Noise (CEEMDAN). The Robust Set Membership Affine Projection (RSMAP) Algorithm is deployed for the enhancement of the obtained fECG signal. RESULT: The results show significant improvements in the elicited fECG signal with a maximum Signal Noise Ratio (SNR) of 31.72 dB and correlation coefficient = 0.899, Maximum Heart Rate(MHR) obtained in the range of 108-142 bpm for all the records of abdominal ECG signals. The statistical test gave a p-value of 0.21 accepting the null hypothesis. The Abdominal and Direct Fetal Electrocardiogram Database (ABDFECGDB) from PhysioNet has been used for this analysis. CONCLUSION: The proposed framework demonstrates a robust and effective method for the elicitation and enhancement of fECG signals from the abdominal recordings.

Effect of dural puncture epidural block technique on fetal heart rate variability during labor analgesia.

PURPOSE: To explore the effect of dural puncture epidural (DPE) block technique on fetal heart rate variability (HRV) during labor analgesia. METHODS: Sixty full-term primiparas who were in our hospital from April 2021 to October 2021 were selected and randomized into epidural analgesia (CEA) and dural puncture epidural analgesia (DPEA) groups (n = 30). After a successful epidural puncture, routine epidural catheter (EC) was performed in CEA group, and spinal anesthesia needle (as an EC) was used to puncture the dura mater to subarachnoid space in DPE group. Anesthetics were injected through EC. The time when the temperature sensation plane reached T10 (W1) and visual analog pain score (VAS), baseline heart rate score, amplitude variation score, cycle variation score, acceleration score, deceleration score, and total score of the first contraction after W1 were recorded. Apgar scores at 1 min, 5 min, and 10 min of neonates after delivery were recorded. RESULTS: The onset time of anesthesia in CEA group was significantly longer than that in DPEA group (p < .05). However, there are no significant differences in W1, VAS, baseline heart rate score, amplitude variation score, cycle variation score, acceleration score, deceleration score, and total score of the first contraction after W1 between the two groups (p > .05). Moreover, the Apgar scores at 1 min, 5 min and 10 min of neonates after delivery were not notably different between the two groups (p > .05). CONCLUSION: Compared with CEA, DPE block technique in labor analgesia relieves maternal pain without adverse effects on fetal HRV and newborns.

[Retrospective study of 60 cases of uterine rupture at the Maternity Center of Monastir, Tunisia]. / Etude rétrospective sur 60 cas de rupture utérine du centre de maternité de Monastir, Tunisie.

Uterine rupture is a life-threatening obstetric complication. The purpose of this study was to investigate the epidemiological features, maternal and foetal prognosis and different treatment options for uterine rupture in healthy and scarred uteri. We conducted a retrospective monocentric descriptive and analytical study of 60 cases of uterine rupture collected in the Department of Gynaecology-Obstetrics of the Center of Maternity and Neonatology, Monastir, from 2017 to 2021. Patients were classified according to the presence or absence of a uterine scar. Sixty patients were enrolled in the study. The majority of cases of rupture occurred in patients with scarred uterus (n=55). The most common clinical sign was abnormal foetal heart rate. No maternal deaths were recorded and perinatal mortality rate was 11%. Mean BMI, fetal macrosomia rate and mean parity were significantly higher in the healthy uterus group than in the scarred uterus group (p=0.033, 0.018, and 0.013, respectively). The maternal complications studied (post-partum haemorrhage, hysterectomy, blood transfusion, prolonged hospitalisation) were significantly more frequent in patients with unscarred uterine rupture (p=0.039; p=0.032; p=0.009; p=0.025 respectively). Uterine rupture is a life-threatening obstetrical event for the foetus and the mother. Fetal heart rate abnormality is the most common sign associated with uterine rupture. Management is based on conservative treatment in most cases. Patients with scarred uterus have a better prognosis.

Risk Factors Are Not Very Risky Once a Normal Embryonic Heart Rate is Seen in Early Pregnancy.

OBJECTIVES: To assess first-trimester prognosis when an early pregnancy sonogram demonstrates a normal embryonic heart rate and to determine how a number of risk factors affect prognosis. METHODS: Our study population consisted of 6597 first-trimester scans with gestational age (GA) ≤ 7.0 weeks (all with crown-rump length [CRL] <10 mm), normal embryonic heart, and known first-trimester outcome. We recorded GA; CRL; heart rate; first-trimester outcome; maternal age; presence, absence, and size of subchorionic hematoma; presence or absence of vaginal bleeding; and presence, absence, and size of uterine fibroids. We assessed first-trimester outcome in the study population and subsets based on the above data. RESULTS: First-trimester outcome was successful in 6030 of the 6597 cases (91.4%). The prognosis was somewhat worse with each of the following risk factors: maternal age ≥35 years, large subchorionic hematoma, and large or multiple uterine fibroids (P < .02, chi-squared or Cochran's test for trend, for all of these items). The rate of successful outcome was in the range of 83-88% with each of these risk factors and 93.8% in the absence of any of these factors. CONCLUSIONS: The presence of a normal embryonic heart rate on an early first-trimester sonogram is a reassuring finding, indicating a likelihood of good first-trimester outcome of at least 83% even in the presence of risk factors, and of over 90% in the absence of such factors.

Fetal magnetocardiographic recordings with a prototype bed-based array system of optically-pumped magnetometers.

OBJECTIVE: To record and extract features of fetal cardiac activities with a semi-rigid prototype optically-pumped magnetometers (OPM) sensor array. METHODS: Fetal magnetocardiography (fMCG) data were collected from 15 pregnant women between 28 and 40 weeks gestation. Mothers were lying flat in a customized bed with sensors touching their abdomen from below using a prototype grid. fMCG was extracted to perform standard fetal heart rate variability (FHRV) analysis. RESULTS: fMCG was observed in 13 of the 15 pregnant women. OPM FHRV indicators were in the range of previous SQUID studies. CONCLUSION: Semi-rigid prototype OPM system has the ability to record quality fMCG. fMCG is capable of identifying lethal cardiac rhythm disturbances in the fetus. Our novel application of OPM technology may lower costs and increase maternal comfort, thus expanding fMCG's generalizability.

Transcutaneous Discrimination of Fetal Heart Rate from Maternal Heart Rate: A Fetal Oximetry Proof-of-Concept.

Intrapartum care uses electronic fetal heart rate monitoring (EFHRM) for over 50 years to indirectly assess fetal oxygenation. However, this approach has been associated with an increase in cesarean delivery rates and limited improvements in neonatal hypoxic outcome. To address these shortcomings, a novel transabdominal fetal pulse oximeter (TFO) is being developed to provide an objective measurement of fetal oxygenation. Previous studies have evaluated the performance of TFO on pregnant ewe. Building on the animal model, this study aims to determine whether TFO can successfully capture human fetal heart rate (FHR) signals during non-stress testing (NST) as a proof-of-concept. Eight ongoing pregnancies meeting specific inclusion criteria (18-40 years old, singleton, and at least 36 weeks' gestation) were enrolled with consent. Each study session was 15 to 20 min long. Reference maternal heart rate (MHR) and FHR were obtained using finger pulse oximetry and cardiotocography for subsequent comparison. The overall root-mean-square error was 9.7BPM for FHR and 4.4 for MHR, while the overall mean-absolute error was 7.6BPM for FHR and 1.8 for MHR. Bland-Altman analysis displayed a mean bias ± standard deviation between TFO and reference of -3.9 ± 8.9BPM, with limits of agreement ranging from -21.4 to 13.6 BPM. Both maternal and fetal heart rate measurements obtained from TFO exhibited a p-value < 0.001, showing significant correlation with the reference. This proof-of-concept study successfully demonstrates that TFO can accurately differentiate maternal and fetal heart signals in human subjects. This achievement marks the initial step towards enabling fetal oxygen saturation measurement in humans using TFO.

Effect of Direct and Mediated through Maternal Organism Activation of the Catecholaminergic System on Heart Rate Parameters in Rat Fetuses.

We performed a comparative analysis of direct and mediated through the maternal organism effects of elevated catecholamine concentration on changes in the cardiac activity parameters in female rats and their fetuses on gestation days 18 and 20 under in vivo conditions. Administration of L-DOPA, a precursor of catecholaminergic transmitters, did not cause chronotropic effects in fetuses. Analysis of HR variability showed that in fetuses, irrespective of the administration route, there was an increase in nervous influences while the leading role of humoral-metabolic factors in the regulation of HR was preserved. In females receiving L-DOPA injection on day 18 of gestation, a decrease in humoral-metabolic and an increase in nerve effects were observed; in rats injected with L-DOPA on day 20 of gestation, an increase in sympathetic influences was found. Administration of L-DOPA to fetuses provoked a slight increase in the power of all components of the heart rhythm periodogram spectrum in females on day 18 of gestation and their decrease on day 20. Changes in the parameters of HR variability in females can confirm the hypothesis that in the "mother-fetus" system, the heart rhythm in the mother can be affected by both maternal and fetal influences presumably through the humoral-metabolic regulation.

How pregnant women with diabetes experience telemonitoring of the fetal heart rate - An interview study.

OBJECTIVES: The use of telemonitoring in healthcare is generally increasing. Women with complicated pregnancies are using telemonitoring as an alternative to conventional management, encompassing hospitalization or frequent outpatient clinic visits. However, there is sparse evidence on how pregnant women experience monitoring of their unborn babies at home. Women might feel uncomfortable with this responsibility, and moreover they might miss face-to-face contact with healthcare personnel. STUDY DESIGN: The study setting was a Danish hospital with a tertiary obstetric unit attending approximately 3400 births annually. A qualitative study design with interview as method included 11 pregnant women with type 1 diabetes or Gestational Diabetes Mellitus. This design was used to investigate how pregnant women with complicated pregnancies experienced telemonitoring of the fetus. Reflexive thematic analysis was used to analyze the pregnant women's experiences of telemonitoring. RESULTS: Women with type 1 diabetes or Gestational Diabetes Mellitus found the advantages of telemonitoring to outweigh the disadvantages. They experienced telemonitoring as time-saving and that telemonitoring decreased the level of stress. Moreover, telemonitoring supports positive collaboration with healthcare professionals. The women also experienced a lack of coordination of consultations between different departments at the hospital and challenges with timing, feedback, and technical issues. Moreover, the women requested an opportunity to discuss family formation and emotions. CONCLUSIONS: Pregnant women with type 1 diabetes or Gestational Diabetes Mellitus benefit from the use of telemonitoring. To further improve the implementation and use of telemonitoring clinical implications, consider how timing and coordination of care, technical equipment, and feedback mechanisms could be improved.

Multicentric intelligent cardiotocography signal interpretation using deep semi-supervised domain adaptation via minimax entropy and domain invariance.

BACKGROUND AND OBJECTIVE: Obstetricians use Cardiotocography (CTG), which is the continuous recording of fetal heart rate and uterine contraction, to assess fetal health status. Deep learning models for intelligent fetal monitoring trained on extensively labeled and identically distributed CTG records have achieved excellent performance. However, creation of these training sets requires excessive time and specialist labor for the collection and annotation of CTG signals. Previous research has demonstrated that multicenter studies can improve model performance. However, models trained on cross-domain data may not generalize well to target domains due to variance in distribution among datasets. Hence, this paper conducted a multicenter study with Deep Semi-Supervised Domain Adaptation (DSSDA) for intelligent interpretation of antenatal CTG signals. This approach helps to align cross-domain distribution and transfer knowledge from a label-rich source domain to a label-scarce target domain. METHODS: We proposed a DSSDA framework that integrated Minimax Entropy and Domain Invariance (DSSDA-MMEDI) to reduce inter-domain gaps and thus achieve domain invariance. The networks were developed using GoogLeNet to extract features from CTG signals, with fully connected, softmax layers for classification. We designed a Dynamic Gradient-driven strategy based on Mutual Information (DGMI) to unify the losses from Minimax Entropy (MME), Domain Invariance (DI), and supervised cross-entropy during iterative learning. RESULTS: We validated our DSSDA model on two datasets collected from collaborating healthcare institutions and mobile terminals as the source and target domains, which contained 16,355 and 3,351 CTG signals, respectively. Compared to the results achieved with deep learning networks without DSSDA, DSSDA-MMEDI significantly improved sensitivity and F1-score by over 6%. DSSDA-MMEDI also outperformed other state-of-the-art DSSDA approaches for CTG signal interpretation. Ablation studies were performed to determine the unique contribution of each component in our DSSDA mechanism. CONCLUSIONS: The proposed DSSDA-MMEDI is feasible and effective for alignment of cross-domain data and automated interpretation of multicentric antenatal CTG signals with minimal annotation cost.

Mapping Early Brain-Body Interactions: Associations of Fetal Heart Rate Variation with Newborn Brainstem, Hypothalamic, and Dorsal Anterior Cingulate Cortex Functional Connectivity.

The autonomic nervous system (ANS) regulates the body's physiology, including cardiovascular function. As the ANS develops during the second to third trimester, fetal heart rate variability (HRV) increases while fetal heart rate (HR) decreases. In this way, fetal HR and HRV provide an index of fetal ANS development and future neurobehavioral regulation. Fetal HR and HRV have been associated with child language ability and psychomotor development behavior in toddlerhood. However, their associations with postbirth autonomic brain systems, such as the brainstem, hypothalamus, and dorsal anterior cingulate cortex (dACC), have yet to be investigated even though brain pathways involved in autonomic regulation are well established in older individuals. We assessed whether fetal HR and HRV were associated with the brainstem, hypothalamic, and dACC functional connectivity in newborns. Data were obtained from 60 pregnant individuals (ages 14-42) at 24-27 and 34-37 weeks of gestation using a fetal actocardiograph to generate fetal HR and HRV. During natural sleep, their infants (38 males and 22 females) underwent a fMRI scan between 40 and 46 weeks of postmenstrual age. Our findings relate fetal heart indices to brainstem, hypothalamic, and dACC connectivity and reveal connections with widespread brain regions that may support behavioral and emotional regulation. We demonstrated the basic physiologic association between fetal HR indices and lower- and higher-order brain regions involved in regulatory processes. This work provides the foundation for future behavioral or physiological regulation research in fetuses and infants.