Twin Infants Research Articles

Assisted Reproductive Technology Surveillance - United States, 2014.

Since the first U.S. infant conceived with assisted reproductive technology (ART) was born in 1981, both the use of ART and the number of fertility clinics providing ART services have increased steadily in the United States. ART includes fertility treatments in which eggs or embryos are handled in the laboratory (i.e., in vitro fertilization [IVF] and related procedures). Women who undergo ART procedures are more likely than women who conceive naturally to deliver multiple-birth infants. Multiple births pose substantial risks to both mothers and infants, including obstetric complications, preterm delivery, and low birthweight infants. This report provides state-specific information for the United States (including the District of Columbia and Puerto Rico) on ART procedures performed in 2014 and compares birth outcomes that occurred in 2014 (resulting from ART procedures performed in 2013 and 2014) with outcomes for all infants born in the United States in 2014.

Retrospective analysis of 55 twin neonates with haemolytic disease of the newborn.

Haemolytic disease is a condition characterized by anaemia and jaundice, and the course may be more complicated in twins. We investigated the demographic and laboratory characteristics of twins with haemolytic disease of the newborn (HDN) and compared these characteristics between groups categorized according to multiple birth status (twins vs. singletons) and conception method (assisted reproductive technology (ART) vs. spontaneous conception). Fifty-five twins with HDN and 253 singletons with HDN who were born during the same period (controls) were included in the study, and we performed comparisons between them. The results showed that twin infants were more likely to be premature, have a low birth weight and be conceived via ART than their singleton counterparts. Moreover, a variety of comorbidities were identified more frequently in twins with HDN than singletons with HDN. The minimum haemoglobin and the initial and maximum total bilirubin, albumin and complement 3 (C3) were all significantly lower in twins than in singletons; however, these two groups were not found to differ significantly by direct antiglobulin test (DAT) status. Twins conceived via ART had a lower minimum haemoglobin and initial bilirubin than twins conceived spontaneously. The results of this study suggested that neonatal comorbidities were more common in twins with HDN than singletons with HDN; however, DAT positivity did not appear to play a major role in the higher rates of comorbidities and lower concentration of haemoglobin observed in twins. Among twins with HDN, conception via ART may serve as a risk factor for increased disease severity.

Prevalence and risk factors of congenital heart defects among live births: a population-based cross-sectional survey in Shaanxi province, Northwestern China

BackgroundNearly half of the population of Northwest China live in Shaanxi province, but population-based data on the epidemiologic characteristics of congenital heart defects (CHD) in this population is limited. The study aimed to investigate the prevalence and epidemiologic characteristics of the CHD among infants born between 2010 and 2013 in Shaanxi province.MethodsInfants born between 2010 and 2013 in Shaanxi province were surveyed using a stratified multi-stage sampling method. Participant characteristics were recorded by questionnaire, medical records were reviewed and CHD was diagnosed using a specialized neonatal echocardiography. A Poisson regression model was applied to assess the association between any CHD and possible risk factors.ResultsA total of 29098 live infants were surveyed with an overall prevalence of 76.0 (95% CI: 66.3, 86.7) per 10000 live infants. The prevalence of major and minor CHD were 26.1 and 49.8 per 10000 live infants, respectively, in surveyed areas. Poisson regression analysis indicated that, compared with singleton infants, the prevalence rate ratio of CHD was higher in twin and multi-fetal infants (PRR:3.1, 95% CI:1.6, 6.1). Using southern Shaanxi as a reference, the PRR of CHD were lower in northern (PRR:0.4, 95% CI:0.3, 0.6) and central Shaanxi province (PRR:0.5, 95% CI:0.4, 0.7). PRR was higher in mothers over 30 years of age than in those under 25 years (PRR:1.6, 95% CI:1.0, 2.5), and in mothers with ≥3 parity than that in mothers with only one parity (PRR:2.2, 95% CI:1.2, 4.2). The risk for CHD among live infants was positively associated with family history of CHD (PRR: 9.8, 95% CI: 5.3, 18.1). Additionally, CHD was less common in the floating population than the permanent population (PRR: 0.6, 95% CI: 0.4, 0.9).ConclusionThe CHD among live infants seemed to be a serious health problem in Shaanxi province as well as in Northwestern China. Our research have important policy implications for recommendations on CHD intervention in Northwest China.

Effect of Prenatal Counseling on Breastfeeding Rates in Mothers of Twins

ObjectiveTo investigate the effect of antenatal breastfeeding counseling on the breastfeeding rates for women who give birth to twins. DesignProspective randomized trial. SettingMultiple Pregnancy Unit, Obstetrics Department, University of São Paulo, Brazil. ParticipantsA total of 171 mothers of twins and their 342 infants. MethodsThe participants were randomized into the prenatal counseling group (PCG) or control group (CG). Breastfeeding data were collected through personal interviews at three times after birth: 30 to 40 days (Time 1), 90 days (Time 2), and 180 days (Time 3). The primary endpoint was a comparison of the mothers' breastfeeding rates between PCG and CG in each analyzed period. The secondary endpoint was the comparison of the overall rates of twin infant breastfeeding between PCG and CG until 180 days after birth. ResultsThe final analysis included 68 women pregnant with twins in the PCG and 60 in the CG. There was no significant difference in the breastfeeding rates between PCG and CG in the analyzed periods: Time 1 (odds ratio [OR] = 1.87, 95% confidence interval [CI] [0.71, 4.95]), Time 2 (OR = 1.50, 95% CI [0.72, 3.10]), and Time 3 (OR = 1.06, 95% CI [0.51, 2.19]). Also, no difference existed in the overall rates of breastfeeding between PCG and CG at 180 days. ConclusionIn women pregnant with twins, antenatal breastfeeding counseling did not significantly affect the breastfeeding rates. Further research about the best moment to counsel mothers of twins is needed to improve breastfeeding rates.

Recovery of acetaminophen-induced fulminant hepatic failure and encephalopathy after ten days of intravenous N-acetylcysteine administration in twin boys

We describe a case of liver failure in twin infants after frequent therapeutic doses of acetaminophen over 4 days at home to manage pyrexia due to a viral illness. The children were treated successfully with intravenous N-acetylcysteine (NAC) following the hospital’s protocol. This case highlights the importance of parental awareness of acetaminophen hepatotoxicity and physicians’ advice to parents in preventing hepatotoxicity induced by acetaminophen overdose during viral illness. Although Twin 1 met the King’s College Hospital criteria for liver transplantation, he was successfully treated with intravenous N-acetylcysteine for 10 days.

Safe Sleep Infant Care Practices Reported by Mothers of Twins.

The high prevalence of prematurity and low birth-weight places twin infants at increased risk for sudden unexpected infant death (SUID) and/or sudden infant death syndrome (SIDS). Risk for these SUID and SIDS is affected by a combination of nonmodifiable intrinsic risk factors and modifiable extrinsic stressors including infant care practices related to sleep. Although adherence to the full scope of American Academy of Pediatrics (AAP) 2011 recommendations is intended to decrease risk, these recommendations are aimed at singleton infants and may require tailoring for families with multiple infants. The study describes infant care practices reported by mothers of twins in the first 6 months postpartum. Mothers caring for twin infants (N = 35) were surveyed online both longitudinally (at 2, 8, 16, and 24 weeks after infant hospital discharge) and cross-sectionally. AAP recommendations (2011) guided survey content. The degree of adherence to AAP recommendations varied over time. For example, mothers of twins reported 100% adherence to placing twins supine for sleep initially, but many reported putting babies on their stomachs for naps as twins became older. Sharing a parent's bedroom decreased over time as did frequency of crib sharing. Fewer than half of mothers offered a pacifier most or all of the time for sleep. Opportunities exist for development of an educational program geared specifically for postpartum parents of twins. Barriers affecting adherence to AAP recommendations and effectiveness of educational programs addressing needs of this unique population need further exploration.

Chest Wall Bulge in 19-day-old Premature Infant

A premature infant (twin 2) presents with a palpable, protruding bulge in the chest wall at age 19 days (Fig 1; Video). Video: Please click here or on video to view premature infant with chest wall bulge. Figure 1. Premature infant with chest wall bulge. ### Prenatal and Birth Histories ### Presentation Twin 2 was diagnosed postnatally with a coarctation of the aorta and underwent repair of this coarctation and a patent ductus arteriosus ligation at age 11 days. Postoperatively, he required a left chest tube, which was removed on postoperative day 1. He was recovering well at 18 days of age, receiving 3 L oxygen via high-flow nasal cannula, with a fraction of inspired oxygen (Fio2) of 0.25, and intermittent tachypnea. His inotropic support had been discontinued and he was tolerating trophic feedings. However, on examination, a well-demarcated bulge overlying the fourth intercostal space of the left upper anterior hemithorax was detected. ### Vital Signs

Diversity of Gut Microbiota Metabolic Pathways in 10 Pairs of Chinese Infant Twins.

Early colonization of gut microbiota in human gut is a complex process. It remains unclear when gut microbiota colonization occurs and how it proceeds. In order to study gut microbiota composition in human early life, the present study recruited 10 healthy pairs of twins, including five monozygotic (MZ) and five dizygotic (DZ) twin pairs, whose age ranged from 0 to 6 years old. 20 fecal samples from these twins were processed by shotgun metagenomic sequencing, and their averaged data outputs were generated as 2G per sample. We used MEGAN5 to perform taxonomic and functional annotation of the metagenomic data, and systematically analyzed those 20 samples, including Jaccard index similarity, principle component, clustering, and correlation analyses. Our findings indicated that within our study group: 1) MZ-twins share more microbes than DZ twins or non-twin pairs, 2) gut microbiota distribution is relatively stable at metabolic pathways level, 3) age represents the strongest factor that can account for variation in gut microbiota, and 4) a clear metabolic pathway shift can be observed, which speculatively occurs around the age of 1 year old. This research will serve as a base for future studies of gut microbiota-related disease research.

Birthweight percentiles for twin birth neonates by gestational age in China.

Localized birthweight references for gestational ages serve as an essential tool in accurate evaluation of atypical birth outcomes. Such references for twin births are currently not available in China. The aim of this study was to construct up-to-data sex specific birth weight references by gestational ages for twin births in China. We conducted a population-based analysis on the data of 22,507 eligible living twin infants with births dated between 8/01/2006 and 8/31/2015 from all 95 hospitals within the Wuhan area. Gestational ages in complete weeks were determined using a combination of last-menstrual-period based (LMP) estimation and ultrasound examination. Smoothed percentile curves were created by the Lambda Mu Sigma (LMS) method. Reference of the 3rd, 10th, 25th, 50th, 75th, 90th, 97th percentiles birth weight by sex and gestational age were made using 11,861 male and 10,646 female twin newborns with gestational age 26–42 weeks. Separate birthweight percentiles curves for male and female twins were constructed. In summary, our study firstly presents percentile curves of birthweight by gestational age for Chinese twin neonates. Further research is required for the validation and implementation of twin birthweight curves into clinical practice.

Neonatal outcomes of twin pregnancies delivered at late-preterm versus term gestation based on chorionicity and indication for delivery.

To investigate the neonatal outcomes of twin pregnancies delivered at late-preterm versus term gestation based on chorionicity and indication for delivery. This is a retrospective cohort study of women with twin pregnancies delivered at ≥34 weeks of gestation from 1995 to 2014. Subjects were categorized into two groups according to gestational age at delivery: late-preterm group (34-36 weeks) and term group (≥37 weeks). Neonatal outcome measures including neonatal intensive care unit (NICU) admission, mechanical ventilator support, and respiratory distress syndrome (RDS) were compared between the late-preterm and term group based on chorionicity (monochorionic or dichorionic) and delivery indication (elective or non-elective). A total of 1198 twin pregnancies were included in the study: 679 in the late-preterm group and 519 in the term group. Late-preterm twin infants had higher rates of NICU admission, mechanical ventilator support, and RDS than did term twin infants, regardless of the chorionicity and indication for delivery. In the multivariable analysis, late-preterm birth, monochorionicity, and non-elective delivery were independently associated with a significantly higher risk of NICU admission and mechanical ventilator support. The late-preterm birth was associated with a higher risk of adverse neonatal outcome regardless of chorionicity and indication for delivery, and showed significantly increased risk by monochorionicity and non-elective delivery.

Potentially Traumatic Events, Posttraumatic Stress Disorder, and Depression among Adults in Puerto Rico.

The aims of the current study were to examine the prevalence of potentially traumatic events (PTEs), posttraumatic stress disorder (PTSD; data available in males only), and depressive symptoms in a Puerto Rican sample of 678 adult caretakers (50% female) of twins participating in the Puerto Rican Infant Twin Study. The World Health Organization Composite International Diagnostic Interview version 3.0 (CIDI 3.0) was utilized to assess rates of PTEs, PTSD, and depression among male participants while an abbreviated version of the CIDI 3.0 and the Mood and Feelings Questionnaire were administered to females to assess PTEs and depressive symptoms. Significantly more males than females reported exposure to a PTE (76.6% vs. 44.2%, χ2 = 64.44, p < 0.001). In males, endorsement of multiple PTEs was associated with increased level of PTSD symptomatology (β = 0.33, p < 0.001). With regard to depression, a similar dose-response relationship was found in both males and females, with depressive symptoms increasing as number of PTEs increased (βs = 0.15, 0.16, ps < 0.05). Exposure to an attack with a weapon was significantly associated with increased depression symptoms in both males and females (βs = 0.24, 0.20, ps < 0.01, respectively). These findings highlight the need for identification of putative risk and resilience factors among PTE-exposed individuals in Puerto Rico.

Deafness gene mutations in newborns in Beijing

ABSTRACTObjective To determine the incidence of congenital hearing loss (HL) in newborns by the rate of deafness-related genetic mutations. Design Clinical study of consecutive newborns in Beijing using allele-specific polymerase chain reaction-based universal array. Study sample This study tested 37 573 newborns within 3 days after birth, including nine sites in four genes: GJB2 (35 del G, 176 del 16, 235 del C, 299 del AT), SLC26A4 (IVS7-2 A > G, 2168 A > G), MTRNR1 (1555 A > G, 1494 C > T), and GJB3 (538 C > T). The birth condition of infants was also recorded. Results Of 37 573 newborns, 1810 carried pathogenic mutations, or 4.817%. The carrier rates of GJB2 (35 del G, 176 del 16, 235 del C, 299 del AT), GJB3 (538 C > T), SLC26A4 (IVS7-2 A > G, 2168 A > G), and MTRNR1 (1555 A > G, 1494 C > T) mutations were 0.005%, 0.104%, 1.924%, 0.551%, 0.295%, 0.253%, 1.387%, 0.024%, and 0.274%, respectively. Logistic regression analysis indicated no statistically significant relationship between mutations and infant sex, premature delivery, twin status, or birth weight. Conclusions The 235delC GJB2 mutation was the most frequent deafness-related mutation in the Chinese population. Genetic screening for the deafness gene will help detect more cases of newborn congenital HL than current screening practices.

529: The effects of antenatal corticosteroids in twin pregnancies complicated by preterm birth

Data regarding the effects of antenatal corticosteroids (ACS) in twins are limited due to the insufficient number of twin pregnancies enrolled in randomized controlled trials on ACS. Furthermore, the interpretation of available data is limited by the fact that the administration of ACS-to-delivery interval is greater than 7 days in a large proportion of twins, a factor that been shown to affect the efficacy of ACS and has not been controlled for in some of the previous studies. The objective of the current study was to assess the effect of ACS on neonatal outcomes in women with twin pregnancies who completed a course of ACS 1-7 days prior to delivery. In this retrospective cohort study, data on twin infants born between 24+0 and 33+6 weeks and admitted to tertiary neonatal units in Canada during 2010-2013 were obtained from the Canadian Neonatal Network. Neonatal outcomes were compared between twins who received ACS between 24 hours and 7 days prior to delivery (twins-ACS group) and those who did not receive ACS (twins-control group). 1) Out of 3,024 twin neonates who met the inclusion criteria, 1382 (69.5%) received a complete course of ACS 1-7 days prior to delivery and were compared to 607 (30.5%) who did not receive ACS. 2) Neonates in the twins-ACS group had a lower rate of mortality (2% vs. 7%, p<0.001) and grade 3-4 intraventricular hemorrhage (IVH) (7% vs. 12%, p=0.01). 3) Following adjustment for confounding factors including gestational age at delivery, hypertension, outborn status, parity, small for gestational age, and mode of delivery, administration of ACS in twins was associated with a lower odds of neonatal mortality, but was not associated with any of the neonatal morbidity outcomes (Table). 4) Findings were similar for the subgroup of twins delivered at less than 30+0 weeks of gestation. Administration of ACS 1-7 days prior to delivery in twin pregnancies is important as it is associated with a lower odds of neonatal mortality, and the magnitude of effect is similar to that previously observed in singletons.

Klebsiella pneumoniae: Development of Carbapenem Resistance due to Acquisition of bla NDM-1 During Antimicrobial Therapy in Twin Infants with Pneumonia.

Objectives: To identify the mechanism of in vivo development of carbapenem resistance in Klebsiella pneumoniae.Methods: Seven sequential isolates of K. pneumoniae were obtained from twin infants with pneumonia. Antimicrobial susceptibility testing was performed by agar dilution method. Carbapenemases including KPC and MβL were initially screened using phenotypic methods, and carbapenemase-encoding genes were identified by polymerase chain reaction and amplicon sequencing. Plasmids of all clinical isolates and the conjugants of resistant isolates were estimated by S1 pulsed-field gel electrophoresis (PFGE). Molecular typing were conducted by PFGE of XbaI-digested genomic DNA and multilocus sequence typing.Results: For old brother, the first and third isolates were susceptible to meropenem, whereas the second and fourth isolates were resistant (MICs 16 mg/L). The first and second isolates from the young brother were susceptible to meropenem whereas the third isolate was resistant. All the resistant isolates produced NDM-1 metallo-β-lactamase. PFGE of XbaI-digested DNA revealed almost identical patterns with similarity indices of above 92% for all the seven isolates. All the isolates had the same sequence type named sequence type 37 (ST37).Conclusion: To our knowledge, this is the first documented case of development of carbapenem resistance in vivo mediated by NDM-1 metallo-β-lactamase in K. pneumoniae during treatment of pneumonia with meropenem.

Assisted Reproductive Technology Surveillance - United States, 2013.

Assisted Reproductive Technology Surveillance - United States, 2013.

Infant twins’ social interactions with caregivers and same-age siblings

The study of twin behavior offers the opportunity to study differential patterns of social and communicative interactions in a context where the adult partner and same-age peer are equally familiar. We investigated the development of social engagement, communicative gestures, and imitation in 7- to 25-month-old twins. Twin dyads (N=20 pairs) participated in 10-min, semi-structured play sessions, with the mother seated in a chair completing paperwork for half the session, and on the floor with her children for the other half. Overall, twins engaged more with their mothers than with their siblings: they showed objects and imitated speech and object use more frequently when interacting with their mothers than with their siblings. When the mother was otherwise engaged, the twins played with toys separately, observed each other's toy play, or were unengaged. These results demonstrate that adult scaffolding of social interactions supports increased communicative bids even in a context where both familiar peers and adults are available as communicative partners.

High burden of invasive group A streptococcal disease in the Northern Territory of Australia.

Although the incidence of invasive group A streptococcal disease in northern Australia is very high, little is known of the regional epidemiology and molecular characteristics. We conducted a case series of Northern Territory residents reported between 2011 and 2013 with Streptococcus pyogenes isolates from a normally sterile site. Of the 128 reported episodes, the incidence was disproportionately high in the Indigenous population at 69·7/100 000 compared to 8·8/100 000 in the non-Indigenous population. Novel to the Northern Territory is the extremely high incidence in haemodialysis patients of 2205·9/100 000 population; and for whom targeted infection control measures could prevent transmission. The incidences in the tropical north and semi-arid Central Australian regions were similar. Case fatality was 8% (10/128) and streptococcal toxic shock syndrome occurred in 14 (11%) episodes. Molecular typing of 82 isolates identified 28 emm types, of which 63 (77%) were represented by four emm clusters. Typing confirmed transmission between infant twins. While the diverse range of emm types presents a challenge for effective coverage by vaccine formulations, the limited number of emm clusters raises optimism should cluster-specific cross-protection prove efficacious. Further studies are required to determine effectiveness of chemoprophylaxis for contacts and to inform public health response.

Early life dynamics of the human gut virome and bacterial microbiome in infants.

The early years of life are important for immune development and influence health in adulthood. Although it has been established that the gut bacterial microbiome is rapidly acquired after birth, less is known about the viral microbiome (or 'virome'), consisting of bacteriophages and eukaryotic RNA and DNA viruses, during the first years of life. Here, we characterized the gut virome and bacterial microbiome in a longitudinal cohort of healthy infant twins. The virome and bacterial microbiome were more similar between co-twins than between unrelated infants. From birth to 2 years of age, the eukaryotic virome and the bacterial microbiome expanded, but this was accompanied by a contraction of and shift in the bacteriophage virome composition. The bacteriophage-bacteria relationship begins from birth with a high predator-low prey dynamic, consistent with the Lotka-Volterra prey model. Thus, in contrast to the stable microbiome observed in adults, the infant microbiome is highly dynamic and associated with early life changes in the composition of bacteria, viruses and bacteriophages with age.

Zygosity Diagnosis: When Physicians and DNA Disagree.

Physicians and other medical professionals do not always provide new parents with an accurate diagnosis of their twins' zygosity. An overview of this problem is presented, supplemented by an interview with a mother who recently learned that her 2-year-old 'dizygotic (DZ)' twin girls are actually 'monozygotic (MZ)'. Reviews of two case studies, one of twins with sex-discordance and chimerism and the other of twins with congenital amegakaryotic thrombocytopenia, follow. Two additional studies, one a twin analysis of attractiveness to mosquitoes and the other a study of twins coping with crisis, are also described. Several articles and letters from the popular media, concerning less favored twins, paternity issues surrounding superfecundation, twins with late-onset Tay-Sachs disease, and triplets admitted to MIT are informative and insightful.

Improved Perinatal Mortality in Twins--Changing Practice and Technologies.

We set out to examine rates of perinatal mortality in twin pregnancies over a 17-year study period. Changes in mode of delivery were also examined as well as causes of death in twin mortalities. This retrospective cohort study was performed at three large tertiary referral centers from 1996 to 2012. It included all normally formed twin infants with a birth weight more than 500 g. All cases of perinatal mortality in twin pregnancies (infants more than 500 g who suffered an intrauterine or early neonatal (≤ 7 days of age) death were recorded. The changing rate of cesarean delivery as well as varying causes of death in twins over the course of the study were also examined. During the study period, there were 395,830 pregnancies across the three institutions, this included 6,727 twin gestations. The perinatal mortality rate was 21.5/1,000 twin infants. The perinatal mortality rate in twins decreased over the study period (p = 0.0006; R (2) = 0.55; slope = -1.2). Rates of cesarean delivery in twin gestations were found to have increased over the course of the study (p < 0.0001; R (2) = 0.84; slope = 1.7). There were 288 intrauterine and early neonatal deaths in twin infants, 50% (147/288) occurred in twins born extremely premature (< 26 weeks). Prematurity was the leading cause of mortality in twins, followed by twin-to-twin transfusion syndrome (TTTS). TTTS was found to have a decreasing contribution to perinatal mortality during the study (p = 0.008; R (2) = 0.38; slope = -1.5). The perinatal mortality rate in twins improved during the study. The rate of cesarean delivery increased by 1.7% for each year of the study, culminating in a cesarean delivery rate of 62% in 2012. TTTS made a decreasing contribution to the mortality rate in twins during the study.