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Perinatal outcome and congenital malformations in in-vitro fertilization babies from the Bourn-Hallam group.

The perinatal outcome and congenital malformations in children born between 1978 and 1987 in Great Britain after in-vitro fertilization (IVF) at Bourn Hall Clinic and the Hallam Medical Centre are presented. The average maternal age was 34.2 years. Multiple births were frequent, constituting 23% of all deliveries; 19% were twins and 4% triplets. There were no quadruplet or higher order multiple births during that period. Twenty-five per cent of all deliveries were preterm. The mean birth weight was 2793 g and was strongly related to multiplicity of pregnancy and gestational age. Overall, 32% of babies had a low birthweight (less than 2500 g) with 6% having a very low birthweight (less than 1500 g). The overall stillbirth and infant mortality rates were two to three times higher than those of infants born after natural conception in England and Wales; this is attributed to the high incidence of multiple births. The stillbirth rates were 5.07, 20.8 and 24.7 per thousand total births in singletons, twins and triplets respectively. The corresponding figures for perinatal mortality were 13.5, 38.2 and 37 per thousand. Overall, 2.5% of the babies had one or more major congenital malformations diagnosed within one week of life. This was within the range of expected values in the United Kingdom and there was no significant increase in any specific malformation.

Adult↗

The communication abilities of 2- to 4-year-old twins.

The speech and language abilities of pre-school multiple-birth children (MBC) are often reported to be impaired. In this study, teh syntactic, semantic, pragmatic, articulation and phonological skills of 19 sets of MBC were assessed. The comparisons made were between MBC and matched singleton controls, between siblings within multiple-birth sets, and for each multiple-birth child with different conversational partners (sibling versus speech and language therapist). The results indicated that the MBC performed more poorly than the singleton controls on measures of syntax and phonology. Whilst there were quantitative and qualitative similarities between siblings' linguistic abilities, their phonologies were not identical, and the MBC's speech and language changed with different conversational partners. The implications of the results for the existence of 'twin language', choice of language sample for assessment of functional communication and the need for preventive intervention programmes are discussed.

Child Language↗

A prospective study of stress among women undergoing in vitro fertilization or gamete intrafallopian transfer.

OBJECTIVE: To evaluate whether baseline or procedural stress during in vitro fertilization (IVF) or gamete intrafallopian transfer (GIFT) affects pregnancy or live birth delivery rates. DESIGN: Prospective study. SETTING: Seven clinics in Southern California between 1993 and 1998. PATIENT(S): One hundred and fifty-one women completed two questionnaires. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): The number of oocytes aspirated and fertilized, the number of embryos transferred, the achievement of a pregnancy, live birth delivery, and infant outcomes. RESULT(S): Positive-affect negative-affect score at baseline negatively influenced the number of oocytes retrieved and embryos transferred. A higher expectation of pregnancy was associated with greater numbers of oocytes fertilized and embryos transferred. At baseline, the risk of no live birth was 93% lower for women who had the highest positive-affect score compared to those with the lowest score. Furthermore, the score on the Infertility Reaction Scale was related to negative outcomes in live birth delivery, infant birth weight, and multiple births. During the time of the procedure, the PANAS and Bipolar Profile of Moods States results were related to the number of oocytes fertilized and embryos transferred; stress did not affect pregnancy or delivery. CONCLUSION(S): Baseline (acute and chronic) stress affected biologic end points (i.e., number of oocytes retrieved and fertilized), as well as pregnancy, live birth delivery, birth weight, and multiple gestations, whereas (procedural) stress only influenced biologic end points.

Adaptation, Psychological↗

Maternal smoking: an increasing unique risk factor for sudden infant death syndrome in Sweden.

AIM: To assess the change of risk factors that are specific to sudden infant death syndrome (SIDS) after the initialization of a campaign to reduce the risk (RTR) of SIDS compared to non-SIDS postneonatal deaths. METHODS: Data were extracted from the Swedish Medical Birth Registry, 1982-1991 and 1993-1998. 1105 infants died from SIDS during the postneonatal period. 2115 postneonatal deaths were from other causes and 11,050 live birth controls were selected. Risk factors previously identified to be related to SIDS were defined as high parity, prematurity, young maternal age, low Apgar score, birth during the night, single motherhood, multiple births, maternal smoking, male gender, short length standard deviation score (SDS) and small weight-to-length SDS. RESULTS: Non-SIDS deaths were more significantly related to a low 5-min Apgar score, smaller weight-to-length SDS, and/or short length SDS values; while SIDS deaths were more closely related to mothers with higher parity or multiple births, mothers who smoked during pregnancy and single-parent (mother) families. Maternal smoking was even more prominent among SIDS deaths in the post-campaign period. The adjusted odds ratios, compared with non-SIDS deaths, increased from 1.84 (95% CI: 1.48, 2.28) in the pre-campaign period to 4.11 (95% CI: 2.72, 6.21) in the post-campaign period. CONCLUSIONS: Maternal smoking during pregnancy remains the most important modifiable risk factor for SIDS in the post-campaign period in comparison with non-SIDS postneonatal deaths. Other than putting babies in a supine sleeping position, maternal smoking should be the next most important issue to be considered, if there is to be a second campaign.

Adolescent↗

Behavioral problems among twins.

Despite the frequency of multiple births, little information is available to assist parents and health professionals in the identification and management of behavior problems in multiple-birth siblings. Three case reports are presented that describe quarreling, aggression, and feeding problems among twins. To develop intervention strategies most appropriate for the problem behavior, it is important to determine whether (1) parents are able to effectively implement the intervention strategy, (2) behavior is isolated to one sibling, and (3) different reasons are responsible for similar behavior in siblings. Structured observations were used to determine whether the undesired behavior occurred to escape nonpreferred activities, gain access to preferred activities, or obtain parental attention. The cases provide a framework to facilitate the identification and management of common behavior problems occurring among multiple-birth siblings.

Child Behavior Disorders↗

Effect of congenital heart disease on neurodevelopmental outcomes within multiple-gestation births.

OBJECTIVES: We sought to assess the effect of congenital heart disease requiring surgical intervention with cardiopulmonary bypass at 6 months of age or less on developmental outcomes and growth at 1 year of age while controlling for socioeconomic status, prematurity, home environment, and parental intelligence. METHODS: We performed within-family comparison of 11 multiple-gestation births in which one child had congenital heart disease. At 1 year of age, the Bayley Scales of Infant Development II were administered, and growth parameters were assessed. Paired comparisons were made by using fixed effects regression conditioned on family. RESULTS: The multiple-gestation subjects were mildly premature on average (mean gestational age, 35.4 +/- 3.0 weeks). At 1 year of age, children with congenital heart disease scored lower on the Mental Development Index (85.0 +/- 19.3 vs 93.9 +/- 16.0, P = .037) and the Psychomotor Development Index (76.6 +/- 16.9 vs 91.3 +/- 14.9, P = .015) on the Bayley Scales of Infant Development II than did their siblings without congenital heart disease. There were no differences between siblings in weight, height, or head circumference. CONCLUSIONS: The presence of congenital heart disease requiring surgical intervention with cardiopulmonary bypass at 6 months of age or less is associated with a deficit in developmental achievement at 1 year of age, as measured by using the Bayley Scales of Infant Development II.

Female↗

Characteristics of the childbearing population in Europe.

OBJECTIVE: To report the distribution and availability of the indicators describing the population of childbearing women in Europe and to assess the impact of the difference in the distribution of two of these indicators (age and multiple births) on some outcome indicators. METHODS: The six PERISTAT indicators of population characteristics were computed using data from a survey of data providers in Europe. For maternal age and multiple births, the impact on health outcome was simulated for the extremes of the distribution using indirect standardised rates. RESULTS: Data availability is good for basic demographic indicators (age, parity, multiple births), but less complete for indicators of social characteristics (education, smoking, country of birth). Further, common definitions are not used for the latter. Simulations of the impact of maternal age on health outcome found that variation in the maternal age distribution may cause trisomy 21 rates to differ by nearly 20% and maternal mortality ratios by nearly 50%. CONCLUSION: Indicators of basic population characteristics are not collected routinely in every country. The crude distribution of these indicators is essential for international comparisons. Interpretation of comparative data would be improved by collection of health outcomes and service use by maternal characteristics.

Adult↗

Monitoring fetal and infant survival using regional birth notification data in north east London.

OBJECTIVE: To demonstrate the use of aggregated, locally collected birth notification data to examine trends in birth-weight specific survival for singleton and multiple births. DESIGN: Retrospective analysis of 171,527 notified births and subsequent infant survival data derived from computerised community child health records. Validation of data completeness and quality was undertaken by comparison with birth and death registration records for the same period. SETTING: Notifications of births in 1989-1991 to residents of the North Thames (East) Region (formerly North East Thames Regional Health Authority). OUTCOME MEASURES: Birthweight specific stillbirth, neonatal, and postneonatal death rates. RESULTS: There was close correspondence between the notification and registration data. For 96% of the registered deaths a birth notification record was identified and for the majority of these the death was already known to the Community Child Health Computer. Completeness of birth-weight data, particularly at the lower end of the range, was substantially better in birth notification data. Comparison with the most recent published national data relating to birthweight specific survival of very low birthweight singleton and multiple births suggests that the downward trend of mortality is continuing, at least in this Region. CONCLUSIONS: The use of routinely collected aggregated birth notification data provides a valuable adjunct to existing sources of information about perinatal and infant survival, as well as other information regarding process and outcome of maternity services. Such data are required for comparative audit and may be more complete than that obtained from registration or hospital generated data.

Birth Weight↗

Impact of race and ethnicity on the outcome of preterm infants below 32 weeks gestation.

OBJECTIVES: To determine the impact of race/ethnicity on mortality and morbidity such as intraventricular hemorrhage (IVH), periventricular leukomalacia (PVL), bronchopulmonary dysplasia (BPD) and bacteriologically confirmed sepsis, assisted ventilation, surfactant administration, intrauterine growth retardation (IUGR), and patent ductus arteriosus (PDA) among very prematurely delivered infants. STUDY DESIGN: Retrospective study of a cohort of 1006 preterm neonates with gestational age ranging from 22 to 32 weeks discharged from the Neonatal Intensive Care Unit (NICU) between 1998 and 2001. Subgroup analysis according to gestational age (GA) (22 to 24, 25 to 28, and 29 to 32 weeks) and plurality (singleton and multiple) was performed using the chi(2) test and an analysis of variance. RESULTS: Of the 1006 infants, 54.3% were white, 21.7% black, 13.7% Hispanic, and 10.3% were classified as Other. Multiple births among white infants were approximately twice that in (42.4%) black infants (22.1%), and was also significantly higher than in the Hispanic (28.3%) and other race/ethnic groups (25.2%). Overall, a higher proportion of black infants were born with a GA <or=28 weeks (n=115, 55.3%) than white (n=201, 37.1%) and Hispanic (n=53, 38.4%), p<0.05. Therefore, black neonates had a lower GA (27.9+/-2.9 weeks) and birth weight (1170+/-463 g) as compared to white (p<0.0002) and Hispanic infants (p<0.0001). There was no significant impact of race/ethnicity on the mean gestational age in any of the gestational age categories. Infant mortality and morbidity in each gestational age category by race/ethnicity were comparable. The multiple birth black infants were seen to have a lower gestational age and birth weight as compared to singleton black as well as to white, Hispanic and other race/ethnic groups. However, this did not influence morbidity and mortality in multiple birth black neonates. The result of this study showed that the level of prematurity and not plurality predominantly influences the rate of infant mortality and morbidity in each race/ethnic category. CONCLUSIONS: The reduction in gestational age and birth weight in black neonates is not associated with an increased risk of infant mortality and morbidity. In general, the outcomes of black singleton and multiple pregnancies were comparable with those of white, Hispanic and other race/ethnic groups.

Apgar Score↗

[Elective single embryo transfer in assisted reproduction].

BACKGROUND: In Norway, assisted reproduction has been regulated by law since 1987, but the in vitro fertilization (IVF)-clinics are free to decide the number of embryos transferred. During the 1990ies, the number of embryos replaced was reduced from three to two. Triplets almost disappeared, but the twinning rate remained unchanged. According to the latest national data, 27.5 % of the deliveries following IVF and intracytoplasmic sperm injection (ICSI) in 2002 were multiple births. In our hospital, 23.9 % of the deliveries following IVF/ICSI in 2003 were multiple births. To reduce the multiple pregnancy rate, eSET was introduced as a routine in patients with a high probability to become pregnant in November 2004. MATERIAL AND METHODS: The results of eSET from the beginning of November 2004 until July 2005 are presented. All three inclusion criteria for eSET had to be fulfilled: 1) age <or= 35 years, 2) first or second treatment, 3) at least one top quality embryo. RESULTS AND INTERPRETATION: 163 out of 644 treatment cycles fulfilled all three criteria for eSET. For 54 (33 %) of the treated women, the treatment has resulted in live births or ongoing pregnancies, compared to 23 % of the treatments with two transferred embryos. The overall pregnancy rate was only slightly decreased (32.4 %) compared to before implementation of eSET (34 %). In the eSET group, 60 % of the patients had embryos available for cryopreservation. The cumulative pregnancy rate per started treatment cycle is expected to increase when pregnancies following transfer of frozen-thawed embryos are included. The overall twinning rate was reduced to 18.1 %. It should be possible to reduce the twinning rate further by for example raising the age-limit for eSET. An optimal trade-off between cumulative ongoing pregnancy rate and twinning rate could more easily be obtained if the Norwegian IVF-clinics and authorities establish an eSET policy.

Embryo Transfer↗

Influence of body weight, age, and weight gain on fertility and prolificacy in four breeds of ewe lambs.

Breeding ewes to lamb at 1 yr of age can improve profitability for some production systems. The first objective of this study was to evaluate the effect of age and weight at breeding and total postweaning weight gain on reproductive performance of ewe lambs. The second objective was to compare the effects of weight and age variables in four major sheep breeds (Columbia, Polypay, Rambouillet, and Targhee). Weights, ages, and the binary traits of fertility (pregnant or nonpregnant) and prolificacy (one lamb born vs. two or more) were collected on 2,055 ewe lambs at the U.S. Sheep Experiment Station, Dubois, ID, from 1984 through 1988. The effects of age and weight at breeding and total weight gain from weaning to breeding on fertility and prolificacy were analyzed with a logit model in a maximum likelihood analyses. Differences (P < 0.001) among breeds for fertility were identified, with a 93% fertility rate for Polypay ewe lambs compared with lower fertility rates in Columbia, Targhee, and Rambouillet ewe lambs (50, 60, and 75%, respectively). The percentage of multiple births (prolificacy rate) also was higher (P < 0.001) in the Polypay (47%) than in Columbia, Targhee, and Rambouillet breeds (1, 13, and 14%, respectively). Averaged across breeds, weight at breeding had a positive effect on fertility and prolificacy (P < 0.001), whereas total weight gain from weaning to breeding had a positive effect only on fertility (P < 0.027). In separate analyses for each breed, increasing age (P < 0.001) and weight at breeding (P < 0.001) increased the probability of pregnancy in Rambouillet ewe lambs. The probability of pregnancy for Targhee ewe lambs increased (P < 0.005) with weight at breeding. Increasing weight at breeding increased (P < 0.004) the probability of multiple births in all breeds. Increasing total postweaning weight gain increased (P < 0.007) the probabilities of multiple births in Rambouillet and Targhee ewe lambs. In conclusion, Polypay ewe lambs were superior in fertility and prolificacy to Columbia, Rambouillet, and Targhee under Western range conditions. Improved reproductive performance of Columbia, Rambouillet, and Targhee ewe lambs may be achieved by increasing age and weight at breeding and postweaning gain.

Age Factors↗

[Triplets, quadruplets and more...].

Theoretically, a woman could bear unlimited number of fetuses. Practically, the human being on the top of his phylogenetic spread, has chosen the singleton birth as its dominant. The anatomical constitution of the woman let her feed no more than two children at the same time. This were probably the reasons for considering the multiple birth as a nature phenomenon. With the time passing, there was a growing body of legends and misunderstandings, based on exagerated histories on their births. Based on world literature, the super multiple births are analyzed.

Adult↗

Infant mortality rates in single, twin and triplet births, and influencing factors in Japan, 1995-98.

The infant mortality rate (IMR) was analysed among single, twin and triplet births during the period from 1995 to 1998 using Japanese Vital Statistics. This study also investigated the effects of order of multiple births and of birthweight on the IMR. Proportions of neonatal deaths among total infant deaths were about 1/2 for singletons and 3/4 for both twins and triplets. Thus, to reduce the IMR, intensive care of multiple births is likely to be very important during the first month of life. The IMR was higher in males than females for both singletons and twins, but not in triplets. Relative risks of the IMR in multiples relative to singletons were 5-fold in twins and 12-fold in triplets. The IMR was higher in the second-born (18 per 1000 live births) than the first-born (16) twin and higher in the third-born (51) than the first-born (31) and the second-born (34) triplet. The higher risk in the second-born than the first-born twin may be related to delivery complications. The IMR decreased rapidly as birthweight increased in singletons, twins, and triplets. IMRs for < or =1500 g were 2.4 per 1000 live births in singletons, 5.9 in twins and 6.1 in triplets. The corresponding proportions of infant deaths were 75%, 33% and 10% respectively. The higher relative risks of multiple births are almost entirely the result of the lower birthweight distribution among twins and triplets. To reduce the IMR, birthweight is an important factor in twins, triplets and singletons. The overall early neonatal death rate decreased as gestational age rose in singletons, twins and triplets. For birthweights <1000 g, higher IMRs were related to gestational ages of <28 weeks.

Birth Order↗

Population based study on the outcome of small for gestational age newborns.

OBJECTIVE: To explore whether and how population based data from a regional quality control programme can be used to investigate the hypothesis that small for gestational age (SGA) very low birthweight infants (VLBW, <1500 g) are at increased risk of death, severe intraventricular haemorrhage (IVH), and periventricular leucomalacia (PVL), but at decreased risk of respiratory distress syndrome (RDS). METHODS: Analyses of population based perinatal/neonatal data (1991-96) from a quality control programme in Lower Saxony, Germany. After assessment of data validity and representativeness, exclusion criteria were defined: birth weight >90th centile, severe malformations, siblings of multiple births, and gestational age (GA) <25 or >29 weeks. Outcomes of interest were death, severe IVH, PVL, and RDS. Multivariable analyses were performed by Cox proportional hazard and logistic regression models. RESULTS: Within the data validation procedure, an increase in proportions of both VLBW (from 0.95% in 1991 to 1.11% in 1996; +17%) and SGA (from 22.7% to 27.4%; +21%) infants became apparent (p<0.05). The study population consisted of 1623 infants (173 SGA). Mortality was 12.1% (n = 196), with an adjusted hazard ratio for SGA infants of 2.54, 95% confidence interval (CI) 1.70 to 3.79. Both groups were at similar risk of severe IVH (adjusted odds ratio 0.93, 95% CI 0.5 to 1.65) and PVL (1.54, 95% CI 0.78 to 2.87), but SGA infants had less RDS (0.57, 95% CI 0.35 to 0.93). Male sex, multiple birth, hypothermia (<35.5 degrees C), and sepsis were associated with IVH and RDS. Infants admitted to hospitals with <36 VLBW admissions/year had increased mortality (adjusted hazard ratio 1.56, 95% CI 1.12 to 2.18). CONCLUSIONS: SGA VLBW infants are at increased risk of death, but not of IVH and PVL, and at decreased risk of RDS. That mortality is higher in smaller hospitals needs further investigation.

Cerebral Hemorrhage↗

Trends in twin birth outcomes and prenatal care utilization in the United States, 1981-1997.

CONTEXT: Multiple births account for an increasing percentage of all low-birth-weight infants, preterm births, and infant mortality in the United States. Since 1981, the percentage of women with multiple births who received intensive prenatal care (defined as a high number of visits, exceeding the recommendation of the American College of Obstetricians and Gynecologists by approximately 1 SD beyond the mean number of visits for women initiating care within each trimester) has increased significantly. OBJECTIVES: To explore the hypothesis that more aggressive management of twin-birth pregnancies may be associated with changes in birth outcomes in this population. DESIGN, SETTING, AND SUBJECTS: Cross-sectional and trend analysis of data from the National Center for Health Statistics' birth and infant death records for all twin births occurring in the United States between 1981 and 1997, excluding those with missing or inconsistent data. MAIN OUTCOME MEASURES: Trends in preterm birth, low birth weight, preterm and term small-for-gestational-age (SGA) births, and infant mortality, by level of prenatal care utilization. RESULTS: The preterm birth rate for twins increased from 40.9% in 1981 to 55.0% in 1997. The percentage of low-birth-weight infants increased from 51.0% to 54.0%. The preterm SGA rate also increased from 11.9% to 14.1%, while the term SGA rate decreased from 30.7% to 20.5%. For women with intensive prenatal care utilization, the preterm birth rate increased from 35.1% to 55.8%, compared with an increase from 50.6% to 59.2% among women with only adequate use. Twin preterm deliveries involving either induction or first cesarean delivery also increased from 21.9% to 27.3% between 1989-1991 and 1995-1997. The twin infant mortality rate for women with intensive prenatal care use declined between 1983 and 1996 and remained lower than the overall twin infant mortality rate. CONCLUSIONS: An apparent increase in medical interventions in the management of twins may result in the seeming incongruity of more prenatal care and more preterm births; however, these data suggest that women with intensive prenatal care utilization also have a lower infant mortality rate. JAMA. 2000;283:335-341

Cross-Sectional Studies↗

[The focus in neonatology].

During the last years, neonatology has greatly improved. In the last decade, mortality and morbidity have decreased: mortality from respiratory failure of prematurity has decreased from 22% to 12%, mortality of the very low birthweight infants under 1000 g fell from 56% to 35% and mortalities related to asphyxia have diminished from 21% to 12% and to malformations from 33% to 28%. Prematurity is now the first cause of neonatal mortality. During this period, the number of babies under 1000 g has increased 4-fold and the number of multiple births increased more than 2-fold from 3% to 7% of the live births of our hospital. Attitudes towards the premature infant have changed, especially towards the extremely small (called the micropremies). The number of disabled children has increased in parallel with the better survival of the very immature newborns who till recently were not resuscitated.

Asphyxia Neonatorum↗

World collaborative report on in vitro fertilization, 2000.

The International Committee for Monitoring Assisted Reproductive Technology's 7th World Report for the year 2000 analyzes wide variations in live and multiple birth rates from 49 countries and six regions by type of assisted reproductive technology, age, number of embryos transferred, and multiple births. More than 460,157 procedures resulted in delivery rate per aspiration for conventional in vitro fertilization (IVF) of 18.6%; for intracytoplasmic sperm injection (ICSI), 20.4%; for egg donation, 32.3% per transfer; and for frozen ET, 12.0% per transfer. Conventional IVF and ICSI twin rates were 26.9% and 26.2%, respectively, and triplet rates were 2.8% and 2.9%, respectively, for an estimated total of approximately 197,000 to 220,000 babies worldwide.

Adult↗

A population-based study of birth defects in Malaysia.

Birth defects are one of the leading causes of paediatric disability and mortality in developed and developing countries. Data on birth defects from population-based studies originating from developing countries are lacking. One of the objectives of this study was to determine the epidemiology of major birth defects in births during the perinatal period in Kinta district, Perak, Malaysia over a 14-month period, using a population-based birth defect register. There were 253 babies with major birth defects in 17,720 births, giving an incidence of 14.3/1000 births, a birth prevalence of 1 in 70. There were 80 babies with multiple birth defects and 173 with isolated birth defects. The exact syndromic diagnosis of the babies with multiple birth defects could not be identified in 18 (22.5%) babies. The main organ systems involved in the isolated birth defects were cardiovascular (13.8%), cleft lip and palate (11.9%), clubfeet (9.1%), central nervous system (CNS) (including neural tube defects) (7.9%), musculoskeletal (5.5%) and gastrointestinal systems (4.7%), and hydrops fetalis (4.3%). The babies with major birth defects were associated with lower birth weights, premature deliveries, higher Caesarean section rates, prolonged hospitalization and increased specialist care. Among the cohort of babies with major birth defects, the mortality rate was 25.2% during the perinatal period. Mothers with affected babies were associated with advanced maternal age, birth defects themselves or their relatives but not in their other offspring, and significantly higher rates of previous abortions. The consanguinity rate of 2.4% was twice that of the control population. It is concluded that a birth defects register is needed to monitor these developments and future interventional trials are needed to reduce birth defects in Malaysia.

Case-Control Studies↗