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PubMed2004

The effect on the fetus of medications used to treat pregnant inflammatory bowel-disease patients.

OBJECTIVES: We reviewed data to investigate the effect of 5-ASA drugs, metronidazole, ciprofloxacin, prednisone, 6-mercaptopurine, azathioprine, and cyclosporine on pregnancy outcomes in patients with inflammatory bowel disease (IBD). METHODS: One hundred and thirteen female patients with a total of 207 documented conceptions were studied. Treatment information included: smoking history (patient and spouse), dates of conception and termination, and outcome of pregnancy (spontaneous abortion, therapeutic abortion, maternal or fetal illness resulting in abortion, premature birth, healthy full-term birth, multiple births, ectopic pregnancy, congenital defects), weight of baby, type of delivery (cesarian section, vaginal), medication history during each trimester (mean dose, maximum dose, frequency). We analyzed the effect on pregnancy outcome of medication use during the first trimester or at any time during the pregnancy. RESULTS: Thirty-nine patients (34.5%) had ulcerative colitis (UC), 73 (64.5%) had crohn's disease (CD), and 1 patient (1%) had indeterminate colitis. For 100 of the 207 conceptions, the patients were on 5-ASA drugs at some time during the pregnancy, 49 on prednisone, 101 on an immunomodulator (6-MP/azathioprine), 27 on metronidazole, 18 on ciprofloxacin, and 2 on cyclosporine. In 85 (31%) of the conceptions, patients were on none of these medications. No significant differences were found among the groups in each pregnancy with respect to outcome (p values 0.091 to 0.9). In multivariate analyses controlling for age of mother, there was no evidence that 5-ASA type drugs or any type of drug influenced pregnancy outcome. CONCLUSIONS: In 113 female patients with 207 conceptions none of the drugs used to treat IBD is associated with poor pregnancy outcomes.

Adolescent↗
PubMed1998

Childhood, infant and perinatal mortality, 1996; social and biological factors in deaths of children aged under 3.

This article comments on statistics recently published by ONS relating to infant and childhood mortality in 1996. Several factors--birthweight, mother's age, marital status of parents, father's social class, mother's country of birth, multiple birth status, and sex--are known to be associated with the risk of mortality in infants under one year of age. For the first time, ONS is now able to analyse the deaths of 1 and 2 year-old children according to these same factors. The results indicate that these factors are also associated with mortality rates in these older children.

Cause of Death↗
PubMed2006

Preterm birth and multiple pregnancy in European countries participating in the PERISTAT project.

OBJECTIVE: To compare rates of preterm birth among multiple births in European countries, to estimate their contribution to overall preterm birth rates and to explore factors which could explain differences between preterm birth rates. DESIGN: Analyses of data from vital statistics, birth registers or national samples of births. SETTING: Eleven member states of the European Union. POPULATION: All live births or representative samples of births at national or regional level for the year 2000 or most recent year. METHODS: Description of rates of preterm birth before 37 and 32 weeks, estimation of population attributable risks (PAR), study of associations between preterm birth rates in multiples and singletons and nonspontaneous labour using Spearman's rank correlation coefficient. MAIN OUTCOME MEASURES: Preterm birth rates, PAR, proportions of deliveries with nonspontaneous onset (caesarean sections before labour or induction of labour). RESULTS: The proportion of multiple births before 37 weeks varied from 68.4% in Austria to 42.2% in the Republic of Ireland. In half of the countries, over 20% of all preterm births were attributable to multiple births. A strong association was found between the proportions of births before 37 weeks among multiple and singleton births (r= 0.81; P < 0.001). An association was observed between the rates of preterm birth and the proportions of deliveries with nonspontaneous onset among twins. CONCLUSIONS: Wide variations in rates of preterm births and deliveries with nonspontaneous onset were found between countries, suggesting marked differences in clinical practice which could have long-term implications for the health of children from multiple births.

Cesarean Section↗
PubMed2000

Avoiding multiple pregnancies in ART: consideration of new strategies.

To maximize pregnancy rates, physicians who perform IVF, often transfer multiple embryos, which increases the multiple birth risk. Multiple birth infants are at significant risk for a number of adverse outcomes including preterm delivery, low birth weight, congenital malformations, fetal and infant deaths and long term morbidity and disability among survivors. Since the ultimate goal for an IVF treatment is the birth of a healthy infant, an important issue for all kinds of assisted reproductive technologies (ART) must be the reduction or elimination of multiple pregnancies. In this article, different strategies to avoid multiple births in ART are discussed.

Female↗
PubMed2002

Oral versus injectable ovulation induction agents for unexplained subfertility.

BACKGROUND: Oral (anti-oestrogens) and injectable (gonadotrophins) ovulation induction agents have been used to increase the number of eggs produced by a woman per cycle in treatment for unexplained subfertility. It is unclear whether there are significant advantages of one type of treatment over the other in this context or in terms of fertility. OBJECTIVES: To assess the efficacy of oral versus injectable ovulation induction agents for unexplained subfertility. SEARCH STRATEGY: The search strategy of the Menstrual Disorders and Subfertility Group was used for the identification of relevant randomised controlled trials. SELECTION CRITERIA: All trials where oral ovulation induction agents were compared with injectable ovulation induction agents in treatment groups generated by randomisation, from couples with unexplained subfertility, were considered for inclusion in the review. DATA COLLECTION AND ANALYSIS: Five randomised controlled trials, including a total of 231 identified couples with unexplained subfertility, were found and included in this review. All trials were assessed for quality criteria. The studied outcomes were pregnancy, live birth, miscarriage, multiple birth, occurrence of ovarian hyperstimulation syndrome and cycle cancellation. MAIN RESULTS: Where trials with important co-interventions were excluded, there was no significant difference in the odds of beneficial outcomes for oral versus injectable ovulation induction agents - live birth per couple (OR 0.06, 95%CI 0.00-1.15), pregnancy per woman (OR 0.33, 95%CI 0.09-1.20); nor of detrimental outcomes for injectable versus oral agents - miscarriage (OR 0.11, 95%CI 0.00-2.84); there were no reported cases of multiple births, cases of ovarian hyperstimulation or discontinued cycles consequent upon overstimulation. Where trials with the co-intervention of a human chorionic gonadotrophin trigger injection (given only in the injectable ovulation induction agent treatment arm) were not excluded there was no significant difference in the odds of live birth per couple (OR 0.40, 95%CI 0.15-1.08). However oral ovulation induction agents had significantly reduced odds of pregnancy per woman compared to injectable ovulation induction agents (OR 0.41, 95%CI 0.17-0.80). For detrimental outcomes, there were no significant differences in the odds of miscarriage (OR 0.61, 95%CI 0.09-4.01) and multiple birth (OR 1.08, 95%CI 0.16-7.03) for injectable versus oral agents. No data were available concerning the occurrence of ovarian hyperstimulation syndrome nor cycle cancellation. REVIEWER'S CONCLUSIONS: There is insufficient evidence to suggest that oral agents are inferior or superior to injectable agents in the treatment of unexplained subfertility. Information on harms is sketchy, and remains compatible with large differences in either direction. Much larger trials than have previously been undertaken are required to provide information on relative harms as well as benefits.

Administration, Oral↗
PubMed2006

The impact of multiple gestations on late preterm (near-term) births.

Multiple pregnancies currently account for 3% of all births in the United States but are disproportionately responsible for larger rates of prematurity and significant neonatal morbidity. The mean birth age for most multi-fetal pregnancies occurs during the late preterm period when both spontaneous preterm labor and iatrogenic premature birth because of obstetrical or maternal complications are common. Multiples pose numerous unique challenges, emphasizing the significant impact of plurality on late preterm births.

Female↗
PubMed2003

The impact of multiple preterm births on the family.

As the number of multiple births has steadily risen over the past 20 years, twins and triplets form an increasingly large proportion of the preterm population. This causes a number of stresses to their families. Addressing the cause of the epidemic of iatrogenic multiple births is the most effective way to reduce the number of preterm infants and the long-term problems to which they are prone.

Child↗
PubMed1998

Prevention of preterm birth in multiple pregnancy.

Preterm birth is the greatest threat to the infants in a multiple pregnancy. This chapter focuses on strategies that aim to prevent preterm birth and concentrates on the evidence derived from randomized clinical trials and systematic review of randomized clinical trials. The options to avoid a multiple pregnancy are briefly considered. Interventions that aim to prolong pregnancy, including prophylactic cervical cerclage, prophylactic tocolysis, home uterine activity monitoring and hospitalization for bed rest, are critically appraised, as are interventions that aim to improve the outcome of preterm birth. Interventions that require additional evaluation are highlighted.

Female↗
PubMed2004

Trends in place of birth for preterm infants in New South Wales, 1992-2001.

OBJECTIVE: To examine trends in preterm births, especially those less than 33 weeks gestation, occurring in perinatal centres in New South Wales (NSW) from 1992 to 2001. METHODS: Population data were obtained from the NSW Midwives' Data Collection. Trends in the proportion of births in perinatal centres by gestation and by type of preterm birth (spontaneous or elective), and in Apgar scores and neonatal mortality were determined. RESULTS: The preterm birth rate increased from 6.1% in 1992 to 6.7% in 2001. Factors contributing to the increase in preterm births were multiple births and elective preterm deliveries. Births less than 33 weeks gestation in perinatal centres increased from 76% to 83% and for multiple births from 77% to 87%. This coincided with a decrease in 1-minute Apgar scores less than 4 but no significant change in 5-minute Apgar scores or neonatal mortality. CONCLUSIONS: Progress has been made towards the National Health and Medical Research Council guideline that births less than 33 weeks gestation occur in perinatal centres. Preterm births are increasing, creating greater demands for neonatal intensive care unit care and ventilation services.

Apgar Score↗
PubMed1999

Deliveries and children born after in-vitro fertilisation in Sweden 1982-95: a retrospective cohort study.

BACKGROUND: In-vitro fertilisation is an effective treatment for infertility, but there is concern about the health of children. We investigated, in a retrospective registry study, malformations, cancers, and deaths in the complete Swedish in-vitro-fertilisation birth cohort compared with the general population. METHODS: We collected data from all in-vitro-fertilisation clinics in Sweden and compared the obstetric outcomes of babies (n=5856) born between 1982 and 1995 with all babies born in the general population (n=1,505,724) during the same period, according to data from the Swedish Medical Birth Registry and the Registry of Congenital Malformations. We investigated the incidence of childhood cancer through the Swedish Cancer Registry. Data were stratified for maternal age, parity, previous subfertility, year of birth, and multiple of pregnancies. FINDINGS: Multiple births occurred in 27% of pregnancies compared with 1% in the control group. In the in-vitro-fertilisation group, more babies were born preterm (<37 weeks) than controls (30.3 vs 6.3%) and more had low birthweights (<2500 g, 27.4 vs 4.6%). The perinatal mortality was 1.9% in the in-vitro fertilisation group and 1.1% in the controls. For in-vitro-fertilisation singletons, the risk ratios, adjusted for year of birth, for very preterm birth (<32 weeks) and very low birthweight (<1500 g) were 3.54 (95% CI 2.90-4.32) and 4.39 (3.62-5.32), respectively. Malformations occurred in 5.4% of all babies in the in-vitro-fertilisation group (1.39 [1.25-1.54]), and the rates of neural-tube defects and oesophageal atresia were higher than those in the controls. There was no increase in childhood cancer in the in-vitro-fertilisation group. INTERPRETATION: A high frequency of multiple births and maternal characteristics were the main factors that led to adverse outcomes, and not the in-vitro-fertilisation technique itself. The clinical practice of in-vitro-fertilisation needs to be changed to lower the rate of multiple pregnancy.

Cohort Studies↗
PubMed1996

Obstetric and perinatal outcome of pregnancies following intracytoplasmic sperm injection.

The aim of this study was to describe the obstetric and perinatal outcome for births following intracytoplasmic sperm injection (ICSI). Of 210 infants born, 140 were singletons and 70 were twins. There were no triplets or higher births. The multiple birth frequency was 20%. Overall, 17% of deliveries were preterm, although for singleton pregnancies the incidence was reduced to 9%. The median birth weight of all live born infants was 3168 g and singletons 3470 g. Of all infants, 17% had a low birth weight (<2500 g) and 2% had a very low birth weight (<1500 g). Two major malformations occurred in two singleton children and four minor malformations occurred in four children. This was within the range of expected values in Sweden. Karyotyping was performed in 58 pregnancies. All of them were normal. The perinatal mortality was 0.5%. In conclusion, in this observational study from Sweden of the first infants born after ICSI in our programme, the incidence of multiple births, preterm births, low birth weight babies and congenital malformations was low compared with other series of in-vitro fertilization pregnancies not associated with ICSI.

Birth Weight↗
PubMed2006

Assisted conception and retinopathy of prematurity: 8-year follow-up study.

AIMS: To assess the effect of assisted conception (AC) on retinopathy of prematurity (ROP) and ROP screening. Follow-up to the study by McKibbin et al. METHODS: Retrospective study utilising computerised databases of ROP screening, live births, AC and multiple births between 1st April 2000 and 31st August 2003 at St James's Hospital (SJUH) Leeds. chi(2) tests of significance were used. RESULTS: ROP screening was undertaken in 11/265 (4.2%) of AC births versus 1.6% of all SJUH births. This is significantly less than the 20.3% of AC babies screened in McKibbin et al study (P=<0.01). There was no ROP detected in the 11 AC babies. Of all AC births, 36.9% were one of twins and 1.5% from triplet births compared to 46.0% one of twins and 18.6% one of triplets in McKibbin's study. CONCLUSIONS: The percentage of AC babies requiring ROP screening has fallen since McKibbin et al study which was performed between August 1991 and December 1994. This appears to be at least partially due to the reduced multiple birth rates. This reduction in the multiple birth rates follows evidence that reducing the number of embryos transferred does not reduce the number of couples taking home a baby and Human Fertility and Embryology Association guidelines recommending 'no more than two embryos should be transferred in an IVF cycle'. Changes in clinical practice at SJUH have significantly reduced the likelihood of AC babies requiring ROP screening and developing ROP.

Embryo Transfer↗
PubMedDate not supplied

[Standards of birth weight in Italy].

The Italian standards of birth weight have been computed using information routinely collected by the Italian Central Institute of Statistics on about 1,200,000 births in the period 1984-1985. Individual records include data on birth weight and main fetal and maternal characteristics and delivery modalities. The crude and smoothed 5th, 10th, 50th, 90th and 95th centiles of weight at birth as function of gestational age according to sex, type of birth, maternal age and parity are presented. Centiles of weight at birth were higher (about 5%) in males than in females in all gestational ages: for example the 50th centile of weight at 40 weeks gestation was 3479 g in males and 3332 g in females. Between the 28th and the 32nd week the 50th centile of birth weight for multiple births grew at a rate similar to that of singletons; but beyond 32 weeks the weight growth in multiple birth was markedly lower than in singleton ones, the median multiple birth weight reaching the 10th centile of singleton at 38 weeks. The values of centiles increased with parity in both sexes and all gestational ages. The difference was however limited: for example with reference to the 50th centile the value for births in women reporting three or more births was about 5% higher than in those reporting no previous birth. Likewise, centiles of weight were higher in older women, but the difference tended to disappear after 36 weeks gestation. This analysis shows from a large national data-set standards of weight at birth from a Southern European population, providing to obstetrics and perinatologists curves of fetal growth more directly representative of the population under their care.

Adolescent↗
PubMed2006

Assisted reproductive technology surveillance--United States, 2003.

PROBLEM/CONDITION: In 1996, CDC initiated data collection regarding assisted reproductive technology (ART) procedures performed in the United States, as mandated by the Fertility Clinic Success Rate and Certification Act (FCSRCA) (Public Law 102-493, October 24, 1992). ART includes fertility treatments in which both eggs and sperm are handled in the laboratory (i.e., in vitro fertilization and related procedures). Patients who undergo ART treatments are more likely to deliver multiple-birth infants than women who conceive naturally. Multiple births are associated with increased risk for mothers and infants (e.g., pregnancy complications, premature delivery, low-birthweight infants, and long-term disability among infants). REPORTING PERIOD COVERED: 2003. DESCRIPTION OF SYSTEM: CDC contracted with the Society for Assisted Reproductive Technology (SART) to obtain data from ART medical centers located in the United States. Since 1997, CDC has compiled data related to ART procedures. RESULTS: In 2003, a total of 122,872 ART procedures were reported to CDC. These procedures resulted in 35,785 live-birth deliveries and 48,756 infants. Nationwide, 74% of ART procedures used freshly fertilized embryos from the patient's eggs; 14% used thawed embryos from the patient's eggs; 8% used freshly fertilized embryos from donor eggs; and 4% used thawed embryos from donor eggs. Overall, 42% of ART transfer procedures resulted in a pregnancy, and 35% resulted in a live-birth delivery (delivery of one or more live-born infants). The highest live-birth rates were observed among ART procedures using freshly fertilized embryos from donor eggs (51%). The highest numbers of ART procedures were performed among residents of California (15,911), New York (15,534), Massachusetts (8,813), Illinois (8,676), and New Jersey (8,299). These five states also reported the highest number of infants conceived through ART. Of 48,756 infants born through ART, 51% were born in multiple-birth deliveries. The multiple-birth risk was highest for women who underwent ART transfer procedures using freshly fertilized embryos from either donor eggs (40%) or their own eggs (34%). Number of embryos transferred, embryo availability (an indicator of embryo quality), and patient's age were also strong predictors of multiple-birth risk. Approximately 1% of U.S. infants born in 2003 were conceived through ART. Those infants accounted for 18% of multiple births nationwide. The percentage of ART infants who were low birthweight ranged from 9% among singletons to 94% among triplets or higher order multiples. The percentage of ART infants born preterm ranged from 15% among singletons to 97% among triplets or higher order multiples. INTERPRETATION: Whether an ART procedure resulted in a pregnancy and live-birth delivery varied according to different patient and treatment factors. ART poses a major risk for multiple births. This risk varied according to the patient's age, the type of ART procedure performed, the number of embryos transferred, and embryo availability (an indicator of embryo quality). PUBLIC HEALTH ACTIONS: ART-related multiple births represent a sizable proportion of all multiple births nationwide and in selected states. Efforts should be made to limit the number of embryos transferred for patients undergoing ART. In addition, adverse infant health outcomes (e.g., low birthweight and preterm delivery) should be considered when assessing the efficacy and safety of ART.

Adult↗
PubMed2005

Assisted reproductive technology surveillance--United States, 2002.

PROBLEM/CONDITION: In 1996, CDC initiated data collection regarding assisted reproductive technology (ART) procedures performed in the United States, as mandated by the Fertility Clinic Success Rate and Certification Act (FCSRCA) (Public Law 102-493, October 24, 1992). ART includes fertility treatments in which both eggs and sperm are handled in the laboratory (i.e., in vitro fertilization and related procedures). Patients who undergo ART treatments are more likely to deliver multiple-birth infants than women who conceive naturally. Multiple births are associated with increased risk for mothers and infants (e.g., pregnancy complications, premature delivery, low-birthweight infants, and long-term disability among infants). REPORTING PERIOD: 2002. DESCRIPTION OF SYSTEM: : CDC contracts with the Society for Assisted Reproductive Technology (SART) to obtain data from ART medical centers located in the United States. Since 1997, CDC has compiled data related to ART procedures. RESULTS: In 2002, a total of 115,392 ART procedures were reported to CDC. These procedures resulted in 33,141 live-birth deliveries and 45,751 infants. Nationally, 74% of ART procedures used freshly fertilized embryos from the patient's eggs; 14% used thawed embryos from the patient's eggs; 8% used freshly fertilized embryos from donor eggs; and 3% used thawed embryos from donor eggs. Overall, 42% of ART transfer procedures resulted in a pregnancy, and 34% resulted in a live-birth delivery (delivery of one or more live-born infants). The highest live-birth rates were observed among ART procedures using freshly fertilized embryos from donor eggs (50%). The highest numbers of ART procedures were performed among residents of California (15,117), New York (13,276), Massachusetts (8,631), New Jersey (7,744), and Illinois (7,492). These five states also reported the highest number of infants conceived through ART. Of 45,751 infants born through ART, 53% were born in multiple-birth deliveries. The multiple-birth risk was highest for women who underwent ART transfer procedures using freshly fertilized embryos from either donor eggs (42%) or their own eggs (35%). Number of embryos transferred, embryo availability (an indicator of embryo quality), and patient's age were also strong predictors of multiple-birth risk. Approximately 1% of U.S. infants born in 2002 were conceived through ART. Those infants accounted for 17% of multiple births nationally. The percentage of ART infants who were low birth rate ranged from 9% among singletons to 95% among triplets or higher order multiples. The percentage of ART infants born preterm ranged from 15% among singletons to 97% among triplets or higher order multiples. INTERPRETATION: Whether an ART procedure resulted in a pregnancy and live-birth delivery varied according to different patient and treatment factors. ART poses a major risk for multiple births. This risk varied according to the patient's age, the type of ART procedure performed, the number of embryos transferred, and embryo availability (an indicator of embryo quality). PUBLIC HEALTH ACTION: ART-related multiple births represent a sizable proportion of all multiple births nationally and in selected states. Efforts should be made to limit the number of embryos transferred for patients undergoing ART. In addition, adverse infant health outcomes (e.g., low birthweight and preterm delivery) should be considered when assessing the efficacy and safety of ART.

Female↗
PubMed2005

Assisted reproductive technologies (ART) in Canada: 2001 results from the Canadian ART Register.

OBJECTIVE: To present the success rates of assisted reproductive technologies (ART) cycles performed in 2001 in Canada. DESIGN: Retrospective cohort study. SETTING: Nineteen of 22 ART centers in Canada. PARTICIPANTS: Couples undergoing ART treatment in Canada during 2001. METHODS: Data on each ART cycle performed during 2001 were submitted electronically to the Canadian ART Register (CARTR) by participating centers. MAIN OUTCOME MEASURE(S): Clinical pregnancy and live birth rate per cycle started, multiple birth rate. RESULT(S): A total of 7,884 ART cycles was reported to CARTR. There were 5,393 in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) cycles using the woman's own oocytes. Per cycle started, the pregnancy rate was 28.3%, and the live birth rate was 23.1%; the multiple birth rate per delivery was 32.8%. Of cycles with oocytes retrieved, IVF was performed in 44% and ICSI in 56%; the outcomes were similar with the two procedures. There were 301 IVF/ICSI cycles using donor oocytes. The pregnancy rate was 29.2%, and the live birth rate was 22.4%; the multiple birth rate was 43.5%. There were 1,936 frozen embryo transfer cycles using the woman's own oocytes. The pregnancy rate was 18.9%, and the live birth rate was 15.4%; the multiple birth rate was 24.9%. CONCLUSION(S): For 2001, CARTR achieved 86% voluntary participation from Canadian ART centers. Pregnancy and live birth rates comparable to those of other countries were achieved.

Adult↗
PubMed2004

Assisted reproductive technology surveillance--United States, 2001.

PROBLEM/CONDITION: In 1996, CDC initiated data collection regarding assisted reproductive technology (ART) procedures performed in the United States to determine medical center-specific pregnancy success rates, as mandated by the Fertility Clinic Success Rate and Certification Act (FCSRCA) (Public Law 102-493, October 24, 1992). ART includes fertility treatments in which both eggs and sperm are handled in the laboratory (i.e., in vitro fertilization and related procedures). Patients who undergo ART treatments are more likely to deliver multiple-birth infants than women who conceive naturally. Multiple births are associated with increased risk for mothers and infants (e.g., pregnancy complications, premature delivery, low-birthweight infants, and long-term disability among infants). REPORTING PERIOD: 2001. DESCRIPTION OF SYSTEM: CDC contracts with a professional society, the Society for Assisted Reproductive Technology (SART), to obtain data from fertility medical centers located in the United States. Since 1997, CDC has compiled data related to ART procedures. The Assisted Reproductive Technology Surveillance System was initiated by CDC in collaboration with the American Society for Reproductive Medicine, the Society for Assisted Reproductive Technology, and RESOLVE: The National Infertility Association. RESULTS: In 2001, a total of 29,344 live-birth deliveries and 40,687 infants resulting from 107,587 ART procedures were reported from 384 medical centers in the United States and U.S. territories. Nationally, 80,864 (75%) of ART treatments used freshly fertilized embryos from the patient's eggs; 14,705 (14%) used thawed embryos from the patient's eggs; 8,592 (8%) used freshly fertilized embryos from donor eggs; and 3,426 (3%) used thawed embryos from donor eggs. Overall, 40% of ART procedures that progressed to the transfer stage resulted in a pregnancy; 33% resulted in a live-birth delivery (delivery of > or =1 infant); and 21% resulted in a singleton live birth. The highest live-birth rates were observed among ART procedures using freshly fertilized embryos from donor eggs (47%). The greatest numbers of ART procedures were performed among residents of California (13,124), New York (12,379), Massachusetts (8,151), Illinois (7,933), and New Jersey (6,011). These five states also reported the highest number of live-birth deliveries and infants born as a result of ART. The ratio of number of ART procedures per million population ranged from 74 in Idaho to 1,273 in Massachusetts, with a national average of 371 ART procedures started per million persons. Among ART treatments in which freshly fertilized embryos from the patient's eggs were used, substantial variation in live birth rates by patient (e.g., women aged < or =40 years) and treatment characteristics (e.g., ovulatory dysfunction, endometriosis, or unexplained infertility) was observed. The risk for a multiple-birth delivery was highest for women who underwent ART transfer procedures using freshly fertilized embryos from either donor eggs (42%) or from their own eggs (36%). Among ART transfer procedures in which the patient's own eggs were used, an inverse relation existed between multiple-birth risk and patient age. Number of embryos transferred and embryo availability (an indicator of embryo quality) were also strong predictors of multiple-birth risk. Of the 40,687 infants born, 46% were twins, and 8% were triplet and higher order multiples. The total multiple-infant birth rate was 53%. Approximately 1% of U.S. infants born in 2001 were conceived through ART. Those infants accounted for 16% of multiple births nationally. INTERPRETATION: Whether an ART procedure resulted in a pregnancy and live-birth delivery varied according to different patient and treatment factors. ART poses a major risk for multiple births. This risk varied according to the patient's age, the type of ART procedure performed, the number of embryos transferred, and embryo availability (an indicator of embryo quality). PUBLIC HEALTH ACTION: ART-related multiple births represent a sizable proportion of all multiple births nationally and in selected states. Efforts should be made to limit the number of embryos transferred for patients undergoing ART.

Adult↗