Effects of smoking and fetal hypokinesia in early pregnancy

The Lower Limb Movements of the Fetus in Uterus: A Narrative Review

The fetus movements play an important role in fetal well-being. With the continuous advancement of real-time scanning machines, it is feasible to observe the fetus movement in detail. The characteristics of fetal lower limb movements in prenatal examination have not been systematically investigated. This review proposes the patterns of fetal lower limb movements, the maternal influence on fetal lower limb movements, and the application of fetal lower limb movements for the diagnosis of prenatal diseases. A systematic search of literature on the lower limb movements of the fetus in uterus was performed in the databases, namely, Web of Science and Scopus. Thirty-four publications were selected. This review demonstrates that isolated fetal lower limb movements are rare and always accompanied with the movements of other body segments. Detection of the presence of fetal leg movements seems to be of no diagnostic value for fetuses with prenatal diseases. The isolated lower limb movement was statistically significant different between fetuses of low- and high-risk pregnant women. The coordinated movements of the fetal lower limbs and other parts should be considered when analyzing fetal movements in the future study.

Foetal mouth movements: Effects of nicotine

AIM

To assess whether foetal mouth movement frequency changes across gestation and whether there are differences between cigarette and e-cigarette exposure conditions in comparison to a non-exposed group of foetuses.

METHOD

Pregnant women underwent 4-dimensional (4D) foetal ultrasound scans at 32 weeks (106 scans) and 36 weeks of gestational age (87 scans) at James Cook University Hospital, UK. The 4D scans were coded using the Fetal Observable Movement System (FOMS). Measures of maternal smoking status, stress, depression, anxiety, attachment and time of scan were also collected. There were four exposure groups: non-smokers, light smokers (<10 per day), heavy smokers (11-20 per day) and e-cigarette users.

RESULTS

No significant differences in relative frequency of mouth movements between the exposure groups at 32- and 36 weeks of gestational age were found. Foetal mouth movements declined from 32 to 36 weeks of gestation for non-exposed and e-cigarette-exposed foetuses.

CONCLUSION

Due to variability in foetal behaviour, examining mouth movements alone may not be the most appropriate method for assessing group differences. However, in line with other research, mouth movement frequency declined between 32- and 36 weeks of gestational age. A combination of foetal behavioural assessments is needed to assess the effects of cigarette and e-cigarette exposure on foetal neurobehavioural development.

Maternal buprenorphine treatment and fetal neurobehavioral development

BACKGROUND

Gestational opioid use/misuse is escalating in the United States; however, little is understood about the fetal effects of medications used to treat maternal opioid use disorders.

OBJECTIVE

The purpose of this study was to determine the effect of maternal buprenorphine administration on longitudinal fetal neurobehavioral development.

STUDY DESIGN

Forty-nine buprenorphine-maintained women who attended a substance use disorder treatment facility with generally uncomplicated pregnancies underwent fetal monitoring for 60 minutes at times of trough and peak maternal buprenorphine levels. Data were collected at 24, 28, 32, and 36 weeks gestation. Fetal neurobehavioral indicators (ie, heart rate, motor activity, and their integration [fetal movement-fetal heart rate coupling]) were collected via an actocardiograph, digitized and quantified. Longitudinal data analysis relied on hierarchic linear modeling.

RESULTS

Fetal heart rate, heart rate variability, and heart rate accelerations were significantly reduced at peak vs trough maternal buprenorphine levels. Effects were significant either by or after 28 weeks gestation and tended to intensify with advancing gestation. Fetal motor activity and fetal movement-fetal heart rate coupling were depressed from peak to trough at 36 weeks gestation. Polysubstance exposure did not significantly affect fetal neurobehavioral parameters, with the exception that fetuses of heavier smokers moved significantly less than those of lighter smokers at 36 weeks gestation. By the end of gestation, higher maternal buprenorphine dose was related to depression of baseline fetal cardiac measures at trough.

CONCLUSION

Maternal buprenorphine administration has acute suppressive effects on fetal heart rate and movement, and the magnitude of these effects increases as gestation progresses. Higher dose (≥13 mg) appears to exert greater depressive effects on measures of fetal heart rate and variability. These findings should be balanced against comparisons to gestational methadone effects, relatively good outcomes of buprenorphine-exposed infants, and recognition of the benefits of medication-assisted treatment for pregnant women with opioid use disorders in optimizing pregnancy outcomes.

Breech presentation at term and associated obstetric risks factors-a nationwide population based cohort study

PURPOSE

The aim of this study was to estimate whether breech presentation at term was associated with known individual obstetric risk factors for adverse fetal outcome.

METHODS

This was a retrospective, nationwide Finnish population-based cohort study. Obstetric risks in all breech and vertex singleton deliveries at term were compared between the years 2005 and 2014. A multivariable logistic regression model was used to determine significant risk factors.

RESULTS

The breech presentation rate at term for singleton pregnancies was 2.4%. The stillbirth rate in term breech presentation was significantly higher compared to cephalic presentation (0.2 vs 0.1%). The odds ratios (95% CIs) for fetal growth restriction, oligohydramnios, gestational diabetes, a history of cesarean section and congenital fetal abnormalities were 1.19 CI (1.07-1.32), 1.42 CI (1.27-1.57), 1.06 CI (1.00-1.13), 2.13 (1.98-2.29) and 2.01 CI (1.92-2.11).

CONCLUSIONS

The study showed that breech presentation at term on its own was significantly associated with antenatal stillbirth and a number of individual obstetric risk factors for adverse perinatal outcomes. The risk factors included oligohydramnios, fetal growth restriction, gestational diabetes, history of caesarean section and congenital anomalies.

Ultrasound observations of subtle movements: a pilot study comparing foetuses of smoking and nonsmoking mothers

AIM

One way to assess foetal health of smokers is to ask mothers to count perceived movements, an unreliable method hiding differences in prenatal development. The aim of this pilot study was to assess subtle foetal movements in ultrasound scans and establish whether they differ in foetuses of mothers who smoked and nonsmoking mothers.

METHODS

This longitudinal pilot study recruited twenty mothers (16 nonsmoking; 4 smoking) scanned four times from 24 to 36 weeks gestation (80 ultrasound scans). Two types of fine-grained movements were coded offline and analysed using a Poisson log-linear mixed model.

RESULTS

Foetuses of smoking mothers showed a significantly higher rate of mouth movements compared to foetuses of nonsmoking mothers (p = 0.02), after controlling for maternal stress and depression. As pregnancy progressed, these differences between the smoking and nonsmoking groups widened. Differences between the two groups in the rate of foetal facial self-touch remained constant as pregnancy progressed and were borderline significant (p = 0.07).

CONCLUSION

Rates of foetal mouth movement and facial self-touch differ significantly between smokers and nonsmokers. A larger study is needed to confirm these results and to investigate specific effects, including the interaction of maternal stress and smoking. Additionally, the feasibility of this technique for clinical practice should be assessed.

Smoking, the xenobiotic pathway, and clubfoot

BACKGROUND

Isolated clubfoot is a common orthopedic birth defect that affects approximately 135,000 newborns worldwide. It is characterized by ankle equinus, hindfoot varus, and forefoot adductus. Although numerous studies suggest a multifactorial etiology, the specific genetic and environmental components have yet to be delineated. Maternal smoking during pregnancy is the only common environmental factor consistently shown to increase the risk for clubfoot. Moreover, a positive family history of clubfoot, in conjunction with maternal smoking, increases the risk 20-fold. These findings suggest that genetic variation in smoking metabolism (xenobiotic) genes may increase susceptibility to clubfoot. Based on this reasoning, we interrogated eight candidate genes from the xenobiotic metabolism.

METHODS

Twenty-two single-nucleotide polymorphisms and two null alleles in these genes (CYP1A1, CYP1A2, CYP1B1, CYP2A6, EPHX1, NAT2, GSTM1, and GSTT1) were genotyped in a dataset composed of non-Hispanic white and Hispanic multiplex and simplex families.

RESULTS

Only rs1048943/CYP1A1 had significantly altered transmission in the aggregate and multiplex non-Hispanic white datasets (p = 0.003 and p = 0.009, respectively). Perturbation of CYP1A1 can cause an increase in harmful, adduct-forming metabolic intermediates. A significant interaction between EPHX1 and NAT2 was also found (p = 0.007). Importantly, for CYP1A2, significant maternal (p = 0.03; relative risk [RR] = 1.24; 95% confidence interval [CI], 1.04-1.44) and fetal (p = 0.01; RR = 1.33; 95% CI, 1.13-1.54) genotypic effects were identified, suggesting that both maternal and fetal genotypes can negatively impact limb development. No association was found between maternal smoking status and variation in xenobiotic metabolism genes.

CONCLUSION

Together, these results suggest that xenobiotic metabolism genes are unlikely to play a major role in clubfoot; however, perturbation of this pathway may still play a contributory role.

First-trimester fetal heart rate in mothers with opioid addiction

AIM

To investigate the difference in fetal heart rate of opioid-dependent mothers compared to non-dependent mothers in the first trimester of pregnancy.

DESIGN

The data of 74 consecutive singleton pregnancies of mothers enrolled in a maintenance programme for opioid-dependent women was matched to 74 non-exposed singleton pregnancies by maternal age, crown-rump length, smoking status, ethnic background and mode of conception.

MEASUREMENT

Fetal heart rate measured as part of first-trimester screening by Doppler ultrasound between 11+0 and 13+6 gestational weeks was compared retrospectively.

FINDINGS

The mean fetal heart rate in opioid-dependent mothers was 156.0 beats per minute (standard deviation 7.3) compared to 159.6 (6.5) in controls. The difference in fetal heart rate was significant (P = 0.02). There was a significant difference in mean maternal body mass index (P = 0.01) but not in mean nuchal translucency (P = 0.3), gestational age (0.5), fetal gender (P = 0.3) and parity (P = 0.3) between both groups. Fifty-five per cent (41 of 74) of cases were taking methadone, 30% (22 of 74) buprenorphine and 15% (11 of 74) were taking slow-release morphines throughout the pregnancy.

CONCLUSIONS

In fetuses of opioid-dependent mothers a decreased fetal heart rate can already be observed between 11+0 and 13+6 gestational weeks. The effect of opioid intake needs to be taken into consideration when interpreting fetal heart rate in opioid-dependent mothers at first-trimester screening.

The potential of 4D sonography in the assessment of fetal neurobehavior--multicentric study in high-risk pregnancies

OBJECTIVE

An evolving challenge for obstetrician is to better define normal and abnormal fetal neurological function in utero in order to better predict antenatally which fetuses are at risk for adverse neurological outcome.

PATIENTS AND METHODS

Prenatal neurological assessment in high-risk fetuses using four-dimensional ultrasound applying the recently developed Kurjak antenatal neurodevelopmental test (KANET). Postnatal neurological assessment was performed using Amiel Tison's neurological assessment at term (ATNAT) for all live-borns and general movement (GM) assessment for those with borderline and abnormal ATNAT.

RESULTS

Inclusion criteria were met by 288 pregnant women in four centers of whom 266 gave birth to a live-born baby. It was revealed that 234 fetuses were neurologically normal, 7 abnormal and 25 borderline. Out of 7 abnormal fetuses ATNAT was borderline in 5 and abnormal in 2, whereas GM assessment was abnormal in 5 and definitely abnormal in 2. Out of 25 KANET borderline fetuses, ATNAT was normal in 7, borderline in 17 and abnormal in 1, whereas the GM assessment was as follows: normal optimal in 4, normal suboptimal in 20, and abnormal in 1. In summary, out of 32 borderline and abnormal fetuses ATNAT was normal in 7, borderline in 22 and abnormal in 3; GM assessment was normal optimal in 4, normal suboptimal in 20, abnormal in 6 and definitely abnormal in 2.

CONCLUSION

The sonographic test requires further studies before being recommended for wider clinical practice.

Fetal and offspring arrhythmia following exposure to nicotine during pregnancy

Although recent studies have demonstrated prenatal nicotine can increase cardiovascular risk in the offspring, it is unknown whether exposure to nicotine during pregnancy also may be a risk for development of arrhythmia in the offspring. In addition, in previous studies of fetal arrhythmia affected by smoking, only two patterns, bradycardia and tachycardia, were observed. The present study examined acute effects of maternal nicotine on the fetal arrhythmia in utero, and chronic influence on offspring arrhythmia at adult stage following prenatal exposure to nicotine. Nicotine was administered to pregnant ewes and rats. In the fetal sheep, intravenous nicotine not only induced changes of fetal heart rate, but also caused cardiac cycle irregularity, single and multiple dropped cardiac cycles. Although maternal nicotine had no influence on fetal blood pH, lactic acid, hemocrit, Na(+), K(+) levels and plasma osmolality, fetal blood PO(2) levels were significantly decreased following maternal nicotine in ewes. In offspring rats at 4-5 months after birth, prenatal exposure to nicotine significantly increased heart rate and premature ventricular contraction in restraint stress. In addition, arrhythmias induced by injection of nicotine were higher in the offspring prenatal exposure to nicotine in utero. The results provide new evidence that exposure to nicotine in pregnancy can cause fetal arrhythmia in various patterns besides tachycardia and bradycardia, the possible mechanisms for nicotine-induced fetal arrhythmia included in utero hypoxia. Importantly, following exposure to nicotine significantly increased risk of arrhythmia in the adult offspring. The finding offers new insight for development of cardiac rhythm problems in fetal origins.