Is Obesity a Risk Factor for Disorders of Amniotic Fluid?

OBJECTIVES: Prior studies show conflicting evidence as to whether obesity in the absence of other medical or pregnancy-related conditions contributes to amniotic fluid disorders. The purpose of this study is to determine the association between late-pregnancy obesity with oligohydramnios (amniotic fluid index [AFI] ≤5 cm or maximum vertical pocket [MVP] <2 cm) and/or polyhydramnios (AFI ≥24 cm or MVP ≥8 cm). METHODS: This is a retrospective cohort study of 961 women with singleton gestations who had one or more obstetrical ultrasounds at a single institution at 36 0/7 weeks gestation or beyond between August 1, 2015, and May 1, 2020. Patients were included if they had valid pregnancy dating and a documented AFI and/or MVP. Patients were categorized based on body mass index or BMI (eg, normal, overweight, Class I Obesity, Class II Obesity, or Class III Obesity). RESULTS: A total of 6.2% of patients met criteria for oligohydramnios based on AFI, MVP or both (n = 60). There was no significant association between oligohydramnios and increasing BMI, regardless of obesity class (P = .21). In terms of polyhydramnios, 5.6% of patients met criteria based on AFI, MVP, or both (n = 54). Similarly, there was also no significant association between polyhydramnios and increasing BMI, regardless of obesity class (P = .66). CONCLUSIONS: Elevated maternal BMI was not significantly associated with disorders of amniotic fluid, regardless of the severity of obesity.

Prehypertension in early versus late pregnancy.

INTRODUCTION: Hypertensive disorders play a significant role in maternal morbidity and mortality. Limited data on prehypertension (preHTN) in pregnancy exist. We examine the risk of adverse outcomes in patients with preHTN in early (<20 weeks) versus late pregnancy (>20 weeks). MATERIALS AND METHODS: Retrospective cohort study of singleton gestations between August 2013 and June 2014. Patients were divided based on when they had the highest blood pressure in pregnancy, as defined per the Joint National Committee 7 (JNC-7). Groups were compared using χ2, Fisher's exact, Student's t-test, and Mann-Whitney U test with p < .05 used as significance. RESULTS: There were 125 control, 95 early preHTN, 136 late preHTN, and 21 chronic hypertension (CHTN). Early preHTN had an increased risk of pregnancy-related hypertension (PRH) (OR 12.26, p < .01) and composite adverse outcomes (OR 2.32, p < .01). Late preHTN had an increased risk for PRH (OR 4.39, p = .02) compared with normotensive and decreased risk for PRH (OR 0.26, p = .02), and composite adverse outcomes (OR 0.379, p = .04) compared with CHTN. Compared with late preHTN, early preHTN had more PRH (OR 2.85, p < .01), and composite adverse outcomes (OR 1.68, p = .04). CONCLUSIONS: Early prehypertension increases the risk of adverse obstetrical outcomes. Other than an increased risk of PRH, patients with late prehypertension have outcomes similar to normotensive women.

Erratum: Quark-level analogue of nuclear fusion with doubly heavy baryons.

This corrects the article DOI: 10.1038/nature21697.

Discovery of the Doubly Charmed Ξ_{cc} Baryon Implies a Stable bbu[over ¯]d[over ¯] Tetraquark.

Recently, the LHCb Collaboration discovered the first doubly charmed baryon Ξ_{cc}^{++}=ccu at 3621.40±0.78 MeV, very close to our theoretical prediction. We use the same methods to predict a doubly bottom tetraquark T(bbu[over ¯]d[over ¯]) with J^{P}=1^{+} at 10 389±12 MeV, 215 MeV below the B^{-}B[over ¯]^{*0} threshold and 170 MeV below the threshold for decay to B^{-}B[over ¯]^{0}γ. The T(bbu[over ¯]d[over ¯]) is therefore stable under strong and electromagnetic interactions and can only decay weakly, the first exotic hadron with such a property. On the other hand, the mass of T(ccu[over ¯]d[over ¯]) with J^{P}=1^{+} is predicted to be 3882±12 MeV, 7 MeV above the D^{0}D^{*+} threshold and 148 MeV above the D^{0}D^{+}γ threshold. T(bcu[over ¯]d[over ¯]) with J^{P}=0^{+} is predicted at 7134±13 MeV, 11 MeV below the B[over ¯]^{0}D^{0} threshold. Our precision is not sufficient to determine whether bcu[over ¯]d[over ¯] is actually above or below the threshold. It could manifest itself as a narrow resonance just at threshold.

Quark-level analogue of nuclear fusion with doubly heavy baryons.

The essence of nuclear fusion is that energy can be released by the rearrangement of nucleons between the initial- and final-state nuclei. The recent discovery of the first doubly charmed baryon , which contains two charm quarks (c) and one up quark (u) and has a mass of about 3,621 megaelectronvolts (MeV) (the mass of the proton is 938 MeV) also revealed a large binding energy of about 130 MeV between the two charm quarks. Here we report that this strong binding enables a quark-rearrangement, exothermic reaction in which two heavy baryons (Λc) undergo fusion to produce the doubly charmed baryon and a neutron n (), resulting in an energy release of 12 MeV. This reaction is a quark-level analogue of the deuterium-tritium nuclear fusion reaction (DT → 4He n). The much larger binding energy (approximately 280 MeV) between two bottom quarks (b) causes the analogous reaction with bottom quarks () to have a much larger energy release of about 138 MeV. We suggest some experimental setups in which the highly exothermic nature of the fusion of two heavy-quark baryons might manifest itself. At present, however, the very short lifetimes of the heavy bottom and charm quarks preclude any practical applications of such reactions.

Prehypertension in Early Pregnancy: What is the Significance?

Objective Hypertensive disorders play a significant role in maternal morbidity and mortality. There is limited data on prehypertension (pre-HTN) during the first half of pregnancy. We sought to examine the risk of adverse pregnancy outcomes in patients with prehypertension in early pregnancy (<20 weeks' gestational age). Study Design A retrospective cohort study of 377 patients between 2013 and 2014. Patients were divided based on the highest blood pressure in early pregnancy, as defined per the JNC-7 criteria. There were 261 control patients (69.2%), 95 (25.2%) pre-HTN patients, and 21 (5.6%) chronic hypertension (CHTN) patients. The groups were compared using X2, Fisher's Exact, Student t-test, and Mann-Whitney U test with p < 0.05 used as significance. Results Patients with pre-HTN delivered earlier (38.8 ± 1.9 weeks vs 39.3 ± 1.7 weeks), had more pregnancy related hypertension (odds ratio [OR], 4.62; confidence interval [CI], 2.30-9.25; p < 0.01) and composite maternal adverse outcomes (OR, 2. 10; 95% CI, 1.30-3.41; p < 0.01), NICU admission (OR, 2.21; 95% CI, 1.14-4.26; p = 0.02), neonatal sepsis (OR, 6.12; 95% CI, 2.23-16.82; p < 0.01), and composite neonatal adverse outcomes (OR, 2.05; 95% CI, 1.20-3.49; p < 0.01). Conclusion Although women with pre-HTN are currently classified as normal in obstetrics, they are more similar to women with CHTN. Pre-HTN in the first half of pregnancy increases the likelihood of adverse outcomes.

New Exotic Meson and Baryon Resonances from Doubly Heavy Hadronic Molecules.

We predict several new exotic doubly heavy hadronic resonances, inferring from the observed exotic bottomoniumlike and charmoniumlike narrow states X(3872), Z_{b}(10610), Z_{b}(10650), Z_{c}(3900), and Z_{c}(4020/4025). We interpret the binding mechanism as mostly molecularlike isospin-exchange attraction between two heavy-light mesons in a relative S-wave state. We then generalize it to other systems containing two heavy hadrons which can couple through isospin exchange. The new predicted states include resonances in meson-meson, meson-baryon, baryon-baryon, and baryon-antibaryon channels. These include those giving rise to final states involving a heavy quark Q=c,b and antiquark Q[over ¯]^{'}=c[over ¯],b[over ¯], namely, DD[over ¯]^{*}, D^{*}D[over ¯]^{*}, D^{*}B^{*}, B[over ¯]B^{*}, B[over ¯]^{*}B^{*}, Σ_{c}D[over ¯]^{*}, Σ_{c}B^{*}, Σ_{b}D[over ¯]^{*}, Σ_{b}B^{*}, Σ_{c}Σ[over ¯]_{c}, Σ_{c}Λ[over ¯]_{c}, Σ_{c}Λ[over ¯]_{b}, Σ_{b}Σ[over ¯]_{b}, Σ_{b}Λ[over ¯]_{b}, and Σ_{b}Λ[over ¯]_{c}, as well as corresponding S-wave states giving rise to QQ^{'} or Q[over ¯]Q[over ¯]^{'}.

Abnormal Biochemical Analytes Used for Aneuploidy Screening and Adverse Pregnancy Outcomes in Twin Gestations.

OBJECTIVE: The objective of this study was to determine if first- and second-trimester biochemical markers for aneuploidy have an association with adverse pregnancy outcomes in twin gestations. STUDY DESIGN: A retrospective cohort study of patients who presented with dichorionic diamniotic twin gestations was performed. Patients with first-trimester low pregnancy-associated plasma protein A (PAPP-A) or low free ß human chorionic gonadotropin (ß-hCG), or second-trimester elevated α-fetoprotein (AFP), elevated inhibin A, elevated hCG, or low unconjugated estradiol were identified. The rates of adverse pregnancy outcomes were compared between patients with or without abnormal analytes with p < 0.05 used as significance. RESULTS: In this study, 340 pregnancies were included. Patients with a low PAPP-A had an increased risk for delivery < 37 weeks. Patients with an elevated second-trimester hCG had an increased risk for spontaneous delivery < 28 weeks and neonatal intensive care unit (NICU) admission. Patients with an elevated inhibin A had an increased risk of spontaneous delivery at < 37 and NICU admission. Patients with an elevated AFP had an increased risk of a NICU admission. CONCLUSION: Certain abnormal aneuploidy markers are associated with an increased risk of adverse pregnancy outcomes in twin gestations.

Maternal serum analytes as predictors of IUGR with different degrees of placental vascular dysfunction.

OBJECTIVES: Our primary objective was to determine the association of maternal serum analytes in pregnancies complicated by intrauterine growth restriction (IUGR) stratified by umbilical artery (UA) Doppler versus pregnancies with appropriately grown for gestational age (AGA) and its potential use as screening model. METHODS: Retrospective cohort evaluating first and second trimester maternal serum aneuploidy screening markers in women complicated with IUGR [90 with absent or reversed end diastolic velocity (AREDV), 46 with UA systolic/diastolic ratio ≥95th percentile and 215 with normal UA Doppler] versus 2590 women with AGA fetuses (control). RESULTS: Extreme levels of each analyte were significantly more common in the IUGR/AREDV group than in AGA group: inhibin A >97th percentile [≥2.27 multiples of the median (MoM)], OR: 41 (95% CI: 21-80); unconjugated estriol <3rd percentile (≤0.6 MoM), OR: 17.2 (95% CI: 8.1-42); AFP >97th percentile (≥1.88 MoM), OR: 15 (95% CI: 8.2-27); PAPP-A <3rd percentile (≤0.33 MoM), OR: 13 (95% CI: 6.6-25.5); and free-beta human chorionic gonadotrophin second trimester >97th percentile (≥3.24 MoM), OR: 11.6 (95% CI: 4.2-32). In a subgroup of pregnancies in which all markers were evaluated on each patient, a combination of abnormal markers detected 73% (95% CI: 54-87%) of IUGR/AREDV fetuses. When maternal risk factors were included into the risk calculation, it increased to 91% (95% CI: 76-98%). CONCLUSIONS: Abnormal maternal serum aneuploidy markers preferentially identify those pregnancies at greatest risk of IUGR with AREDV in the UA.

External aortic diameter ratios: a reliable method to diagnose preductal aortic coarctation.

Aortic Coarctation (AC) is associated with sudden infantile death. Current pathological diagnosis depends on absolute vessel size which is prone to errors due to different rates of development. This study explores the use of ratios of the external diameter between the aortic isthmus (AI), ascending aorta (AA) and the descending aortas (DA). Our study found that while the vessel diameter increased with gestational age, the ratios remained constant and are therefore preferable than absolute size. This simple and highly reproducible method will allow more cases of AC that may be misdiagnosed to get a proper pathological diagnosis.