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OBJECTIVE: To estimate expulsion rates among women with postpartum intrauterine device (IUD) placement by timing of insertion, IUD type, and delivery method. DATA SOURCES: We searched PubMed, Cochrane Library, and ClinicalTrials.gov from 1974 to May 2018. METHODS OF STUDY SELECTION: We searched databases for any published studies that examined post-partum placement of a copper IUD or levonorgestrel intrauterine system and reported counts of expulsions. We assessed study quality using the U.S. Preventive Services Task Force evidence grading system. We calculated pooled absolute rates of IUD expulsion and estimated adjusted relative risks (RRs) for timing of postpartum placement, delivery method, and IUD type using log-binomial multivariable regression model. TABULATION, INTEGRATION, AND RESULTS: We identified 48 level I to II-3 studies of poor to good quality. Pooled rates of expulsion varied by timing of IUD placement, ranging from 1.9% with interval placements (4 weeks postpartum or greater), 10.0% for immediate placements (10 minutes or less after placental delivery), and 29.7% for early placements (greater than 10 minutes to less than 4 weeks postpartum). Immediate and early postpartum placements were associated with increased risk of expulsion compared with interval placement (adjusted RR 7.63, 95% CI 4.31–13.51; adjusted RR 6.17, 95% CI 3.19–11.93, respectively). Postpartum placement less than 4 weeks after vaginal delivery was associated with an increased risk of expulsion compared with cesarean delivery (adjusted RR 5.19, 95% CI 3.85–6.99). Analysis of expulsion rates at less than 4 weeks postpartum also indicated that the levonorgestrel intrauterine system was associated with a higher risk of expulsion (adjusted RR 1.91, 95% CI 1.50–2.43) compared with CuT380A. CONCLUSION: Postpartum IUD expulsion rates vary by timing of placement, delivery method, and IUD type. These results can aid in counseling women to make an informed choice about when to initiate their IUD and to help institutions implement postpartum contraception programs.

ObjectivesTo provide updated and more detailed pooled intrauterine device expulsion rates and expulsion risk estimates among women with postpartum intrauterine device placement by timing of insertion, delivery type, and intrauterine device type to inform current intrauterine device insertion practices in the United States.Data sourcesWe searched PubMed, Cochrane Library, and ClinicalTrials.gov through June2019.Study eligibility criteriaWe included all studies, of any study design, that examined postpartum placement of Copper T380A (copper) or levonorgestrel-containing intrauterine devices that reported counts of expulsion.Study appraisal and synthesis methodsWe evaluated intrauterine device expulsion among women receiving postpartum intrauterine devices in the "immediate" (within 10 minutes), "early inpatient" (>10 minutes to

Objective To estimate the absolute and relative risk of venous thromboembolism (VTE) among women who initiate depot medroxyprogesterone acetate (DMPA) immediately postpartum compared with those who do not initiate hormonal contraception. Methods The IBM MarketScan Commercial Claims and Encounters databases were used to identify delivery hospitalizations among women aged 15-44 years during 2005 through 2014. Diagnosis, procedure, and drug codes were used to identify contraception, VTE, and potential confounding chronic or pregnancy-related conditions. Women who initiated DMPA during days 0 through 7 postpartum were compared with women who did not initiate hormonal contraception during days 0 through 7 postpartum. Women were followed from date of delivery through 12 weeks postpartum for the occurrence of VTE, with censoring at hormonal contraception initiation or prescription, hysterectomy, sterilization, or inpatient death. The incidence rate of VTE and 95% CIs were calculated within each group and the incidence rate ratio was calculated comparing the two groups. Results The unadjusted VTE incidence rate through 12 weeks postpartum was 0.42/10,000 women-days in the immediate postpartum DMPA group (34 events among 11,159 women contributing 805,999 days of follow-up) and 0.15/10,000 women-days in the control group (3,107 events among 3,102,011 women contributing 206,180,811 days of follow-up). The incidence rate ratio for VTE was 2.87 (95% CI 2.05-4.03) among women in the immediate postpartum DMPA group compared with women in the control group, adjusting for age alone. After adjusting for age and pregnancy-related and chronic conditions, the adjusted incidence rate ratio for VTE was 1.94 (95% CI 1.38-2.72) among women in the immediate postpartum DMPA group compared with women in the control group. Conclusion Initiation of DMPA immediately postpartum is associated with a low incidence but an increased relative risk of VTE compared with nonuse of hormonal contraception.

Objective To assess the characteristics of IVF cycles for which preimplantation genetic diagnosis (PGD) was used and to evaluate indications for PGD and treatment outcomes associated with this procedure as compared with cycles without PGD with the data from the U.S. National ART Surveillance System. Design Retrospective cohort study. Setting None. Patient(s) Fresh autologous cycles that involved transfer of at least one embryo at blastocyst when available. Intervention(s) None. Main Outcome Measure(s) PGD indications and age-specific reproductive outcomes. Result(s) There were a total of 97,069 non-PGD cycles and 9,833 PGD cycles: 55.6% were performed for aneuploidy screening (PGD Aneuploidy), 29.1% for other reasons (PGD Other), and 15.3% for genetic testing (PGD Genetic). In comparison to non-PGD cycles, PGD Aneuploidy cycles showed a decreased odds of miscarriage among women 35–37 years (adjusted odds ratio [aOR] 0.62; 95% CI, 0.45–0.87) and women >37 years (aOR 0.55; 95% CI, 0.43–0.70); and an increased odds of clinical pregnancy (aOR 1.18; 95% CI, 1.05–1.34), live-birth delivery (aOR 1.43; 95% CI, 1.26–1.62), and multiple-birth delivery (aOR 1.98; 95% CI, 1.52–2.57) among women >37 years. Conclusion(s) Aneuploidy screening was the most common indication for PGD. Use of PGD was not observed to be associated with an increased odds of clinical pregnancy or live birth for women 35 years, but an increased odds of a live-birth and a multiple live-birth delivery among women >37 years.

Background Bleeding irregularities, such as intermenstrual spotting or heavy or prolonged menstrual bleeding, are common among copper-containing intrauterine device (Cu-IUD) users and are one of the leading reasons for method discontinuation. This review evaluates the evidence for effective therapeutic and preventive treatments for bleeding irregularities during Cu-IUD use. Study Design We searched the PubMed database for peer-reviewed articles that were published in any language from inception of the database through March 2012 and were relevant to treatments for irregular bleeding during Cu-IUD use. We used standard abstract forms and grading systems to summarize and assess the quality of the evidence. Results From 1470 articles, we identified 17 articles that met our inclusion criteria. Evidence from two studies of poor quality demonstrated that antifibrinolytic agents or nonsteroidal anti-inflammatory drugs (NSAIDs) have been used for intermenstrual bleeding or spotting among a small number of Cu-IUD users with mixed results. Evidence from 10 studies of fair to poor quality suggested that some NSAIDs may significantly reduce menstrual blood loss or bleeding duration among Cu-IUD users with heavy or prolonged menstrual bleeding. Antifibrinolytic drugs or antidiuretics may also help reduce blood loss. High-dose aspirin was shown to increase blood loss among those with baseline menorrhagia. Evidence from five studies of fair to poor quality suggested that bleeding irregularities among new Cu-IUD users may be prevented with NSAIDs, although one large study of good quality suggested that prophylactic treatment with ibuprofen does not affect continuation of Cu-IUD use. Evidence from two studies of fair to poor quality suggested that antifibrinolytic agents might be helpful in preventing heavy or prolonged menstrual bleeding among new Cu-IUD users. Conclusions Limited evidence suggests that NSAIDs may be effective treatments for bleeding irregularities associated with Cu-IUD use; antifibrinolytic agents and antidiuretics have also been studied as possible treatments in a small number of subjects, but their safety has not been well documented. NSAIDs and antifibrinolytics may also prevent bleeding irregularities among new CU-IUD users. Preventive NSAID use, however, does not impact Cu-IUD continuation.

Objective To examine the associations between hormonal contraceptive use and measures of HIV disease progression and antiretroviral treatment (ART) effectiveness. Study design A prospective cohort study of women with prevalent HIV infection in St. Petersburg, Russia, was conducted. After contraceptive counseling, participants chose to use combined oral contraceptives (COCs), depot-medroxyprogesterone acetate (DMPA), a copper intrauterine device (IUD) or male condoms for pregnancy prevention. Among participants not using ART at enrollment, we used multivariate Cox regression to assess the association between current (time-varying) contraceptive use and disease progression, measured by the primary composite outcome of CD4 decline to 3 , ART initiation or death. Among participants using ART at enrollment, we used linear mixed models to estimate the predicted mean CD4 change at select time points by contraceptive method. Results During a total of 5233months follow-up among participants not using ART with enrollment CD4 ≥350cells/mm 3 ( n =315), 97 experienced disease progression. Neither current use of COCs [adjusted hazard ratio (aHR) 0.91, 95% confidence interval (CI) 0.56–1.48] nor DMPA (aHR 1.28, 95% CI 0.71–2.31) was associated with a statistically significant increased risk for disease progression compared with use of nonhormonal methods (IUD or condoms). Among participants using ART at enrollment ( n =77), we found no statistically significant differences in the predicted mean changes in CD4 cell count comparing current use of COCs (p=.1) or DMPA (p=.3) with nonhormonal methods. Conclusion Hormonal contraceptive use was not significantly associated with measures of HIV disease progression or ART effectiveness among women with prevalent HIV infection. Implications Hormonal contraceptive use was not significantly associated with measures of HIV disease progression or ART effectiveness among women with prevalent HIV infection.

Objectives: To link data from the US assisted reproductive technology (ART) registry with the Massachusetts birth–infant death file to create a comprehensive dataset on the circumstances surrounding conception and maternal and infant outcomes for a population of ART-conceived infants. Methods: The authors sought to link data for 3704 ART-conceived live-born infants from 2703 deliveries in 1997–1998 involving Massachusetts resident mothers who gave birth in Massachusetts, Rhode Island, New Hampshire, or Connecticut to their corresponding Massachusetts birth record using a two-stage algorithm. Maternal and infant dates of birth served as the primary linkage variables. Maternal names for a subset of the ART-conceived infants were obtained and used in the second stage of the algorithm to confirm a sample of records that matched in Stage I, to resolve duplicate matches, and to link unmatched records. Results: In Stage I, 78% of ART deliveries matched with only one Massachusetts record, 2% matched with two records, and 20% remained unmatched. Overall, the complete algorithm using maternal name data for a portion of records yielded an 89% linkage rate. Nearly all of the records that matched during Stage I that were evaluated with maternal name data in Stage II were confirmed as correctly linked. Conclusions: This project confirms that high-yield data linkage can be achieved in the absence of specific identifiers (e.g., name and social security number). Nonetheless, additional matches were achieved when name data were obtained. This linkage creates the first population-based file in the US capturing detailed information on ART births.

To examine rates and risk factors for spontaneous abortion among pregnancies conceived using assisted reproductive technology (ART).Subjects were 62,228 clinical pregnancies resulting from ART procedures initiated in 1996-1998 in US clinics. Spontaneous abortion was based on ART clinic report and was defined as loss of the entire pregnancy. Spontaneous abortion rates for ART pregnancies were compared with spontaneous abortion rates from the National Survey of Family Growth, a population-based survey of US women 15-44 years.The spontaneous abortion rate among ART pregnancies was 14.7%. This was similar to rates among pregnancies reported in the National Survey of Family Growth. Among pregnancies conceived with the patient's oocytes and freshly fertilized embryos, the spontaneous abortion risk ranged from 10.1% among women 20-29 years to 39.3% among women older than 43. Spontaneous abortion risk among pregnancies conceived with donor eggs was 13.1% with little variation by patient age. Spontaneous abortion risk was increased for pregnancies conceived with frozen and thawed embryos and decreased among multiple-gestation pregnancies. Spontaneous abortion risk was increased among women reporting previous spontaneous abortions and ART attempts, and among women who used clomiphene or zygote intrafallopian transfer. Pregnancies conceived by young women, but gestated by a surrogate, were at increased risk for spontaneous abortion in comparison with young women who gestated their own pregnancies.These findings suggest that ART does not pose a risk for spontaneous abortion. Factors related to oocyte or embryo quality are of primary importance in assessing spontaneous abortion risk.

Objective. To examine trends in multiple births conceived using assisted reproductive technology (ART) in the United States between 1997 and 2000 and to estimate the proportion of all US multiple births attributable to ART use. Methods. We analyzed population-based data of 109 519 live-born infants who were conceived in the United States using ART and born between 1997 and 2000 and population-based data of 15 856 809 live-born infants who were delivered in the United States between 1997 and 2000. Multiple birth rates (the number of live-born infants delivered in multiple gestation pregnancies per 1000 live births) and the proportion of all US multiple births attributable to ART were evaluated. Results. The twin rate for ART patients increased between 1997 and 2000, reaching 444.7 per 1000 live births in 2000, whereas the triplet/+ rate declined substantially from 134.3 to 98.7 per 1000 live births from 1997–2000. From 1997–2000, the proportion of multiple births in the United States attributable to ART increased from 11.2% to 13.6%, whereas the proportion attributable to natural conception decreased from 69.9% to 64.5%. In 2000, the proportion of triplet/+ births attributable to ART and to natural conception was 42.5% and 17.7%, respectively. The contribution of ART to multiple births increased substantially with maternal age, from 11.6% for triplet/+ infants born to women aged 20 to 24 to 92.8% for women aged 45 to 49 years. Conclusions. The contribution of ART to twin birth rates continues to increase, but the contribution of ART to triplet/+ birth rates has declined.

Objective To examine rates and risk factors for spontaneous abortion among pregnancies conceived using assisted reproductive technology (ART). Methods Subjects were 62,228 clinical pregnancies resulting from ART procedures initiated in 1996–1998 in US clinics. Spontaneous abortion was based on ART clinic report and was defined as loss of the entire pregnancy. Spontaneous abortion rates for ART pregnancies were compared with spontaneous abortion rates from the National Survey of Family Growth, a population-based survey of US women 15–44 years. Results The spontaneous abortion rate among ART pregnancies was 14.7%. This was similar to rates among pregnancies reported in the National Survey of Family Growth. Among pregnancies conceived with the patient’s oocytes and freshly fertilized embryos, the spontaneous abortion risk ranged from 10.1% among women 20–29 years to 39.3% among women older than 43. Spontaneous abortion risk among pregnancies conceived with donor eggs was 13.1% with little variation by patient age. Spontaneous abortion risk was increased for pregnancies conceived with frozen and thawed embryos and decreased among multiple-gestation pregnancies. Spontaneous abortion risk was increased among women reporting previous spontaneous abortions and ART attempts, and among women who used clomiphene or zygote intrafallopian transfer. Pregnancies conceived by young women, but gestated by a surrogate, were at increased risk for spontaneous abortion in comparison with young women who gestated their own pregnancies. Conclusion These findings suggest that ART does not pose a risk for spontaneous abortion. Factors related to oocyte or embryo quality are of primary importance in assessing spontaneous abortion risk.

Background The existence of a post–tubal-ligation syndrome of menstrual abnormalities has been debated for decades. We used data from the U.S. Collaborative Review of Sterilization to determine whether the likelihood of persistent menstrual abnormalities was greater among women who had undergone tubal sterilization than among women who had not. Methods A total of 9514 women who underwent tubal sterilization and 573 women whose partners underwent vasectomy were followed in a multicenter, prospective cohort study for up to five years by means of annual telephone interviews. All women were asked the same questions about six characteristics of their menstrual cycles in the presterilization and follow-up interviews. Multiple logistic-regression analysis was used to assess the risk of persistent menstrual changes. Results The women who had undergone sterilization were no more likely than those who had not undergone the procedure to report persistent changes in intermenstrual bleeding or the length of the menstr...

Objective: To examine the association between assisted hatching and monozygotic (MZ) twinning. Design: Case-control. Setting: Population-based sample of IVF-ET cycles initiated in U.S. clinics, 1996. Patient(s): The IVF-ET (n = 35,503) cycles and 11,247 resultant pregnancies. Intervention(s): Use of an assisted hatching procedure on embryos transferred. Main Outcome Measure(s): Cases were pregnancies for which number of fetal hearts observed on ultrasound exceeded number of embryos transferred. These pregnancies were considered to contain at least one MZ set of twins. Cases were compared with two control groups: other multiple-gestation pregnancies (≥2 fetal hearts but number of fetal hearts ≤ number of embryos transferred); and singleton pregnancies (1 fetal heart). Result(s): Women with a case pregnancy were more likely to have received embryos treated with assisted hatching procedures than were women in either control group. After adjustment for patient age, number of embryos transferred, prior cycles, infertility diagnosis, intracytoplasmic sperm injection, and whether embryos from the current cycle were cryopreserved for later use, odds ratios and 95% CIs for use of assisted hatching were 3.2 (1.2–8.0), compared with other multiple-gestation pregnancies, and 3.8 (1.8–9.8), compared with singleton pregnancies. Conclusion(s): Assisted hatching may pose a risk for MZ twinning.

Objective To clarify the implications of low levels of immunoglobulin (Ig)-G or IgM anticardiolipin antibodies. Methods Women who underwent clinically indicated testing for antiphospholipid antibodies were divided into four groups based on results: 1) high-positive (lupus anticoagulant or more than 19 IgG binding units of anticardiolipin antibodies; N=131), 2) low-positive IgG (fewer than 20 IgG binding units; N=93), 3) IgM only (more than nine IgM binding units; N=97), and 4) negative (N=153). The development of antiphospholipid antibody-related disorders was assessed for the time interval from initial antibody testing to patient interview. The median study interval for each group was at least 4 years. Forty-five percent of women had repeat testing at the time of interview. Results Women in the high-positive group were more likely to develop at least one new medical complication than those in the low-positive IgG (odds ratio [OR] 4.49, 95% confidence interval [CI] 2.01-10.03), IgM only (OR 6.00, 95% CI 2.65-13.59), and negative (OR 9.11, 95% CI 3.92-21.2) groups. In contrast, the low-positive IgG, IgM only, and negative groups had similar risks for the development of new disorders. Twelve of 129 (9.3%) women in the lowpositive IgG, IgM only, or negative groups had lupus anticoagulant or more than 19 IgG binding units on retesting. Half of these women developed at least one new disorder. Conclusion Women with IgM or low levels of IgG anticardiolipin antibodies comprise distinct populations from those with lupus anticoagulant or moderate to high levels of anticardiolipin antibodies. These women are not at risk for antiphospholipid antibody-related disorders beyond the risk conferred by their medical histories. However, repeat testing is warranted with new or recurrent clinical symptoms.

While evidence on the association between oral contraceptive (OC) use and breast cancer generally suggests little or no increased risk, the question of whether breast cancer risk varies by OC formulation remains controversial. Few studies have examined this issue because large samples and extensive OC histories are required.We used data from a multicenter, population-based, case-control investigation. Women aged 35-64 years were interviewed. To explore the association between OC formulation and breast cancer risk, we used conditional logistic regression to derive adjusted odds ratios, and we used likelihood ratio tests for heterogeneity to assess whether breast cancer risk varied by OC formulation. Key OC exposure variables were ever use, current or former use, duration of use and time since last use. To strengthen inferences about specific formulations, we restricted most analyses to the 2282 women with breast cancer and the 2424 women without breast cancer who reported no OC use or exclusive use of one OC.Thirty-eight formulations were reported by the 2674 women who used one OC; most OC formulations were used by only a few women. We conducted multivariable analyses on the 10 formulations that were each used by at least 50 women and conducted supplemental analyses on selected formulations of interest based on recent research. Breast cancer risk did not vary significantly by OC formulation, and no formulation was associated with a significantly increased breast cancer risk.These results add to the small body of literature on the relationship between OC formulation and breast cancer. Our data are reassuring in that, among women 35-64 years of age, we found no evidence that specific OC formulations increase breast cancer risk.

Nine morphologic patterns of tumor vessels were identified in eyes removed for ciliary body or choroidal melanoma by the examination of tissue sections stained with fluorescein-conjugated Ulex europaeus I using laser scanning confocal microscopy. This technique also highlights intravascular tumor invasion. Each of these nine morphologic patterns of tumor vessels also may be demonstrated by a modification of the periodic acid-Schiff reaction, viewed with a green narrow band pass filter, but this modified histochemical technique does not accurately identify intravascular tumor invasion. Most tumors have a heterogeneous distribution of vascular patterns. Melanomas in two groups of 20 tumors each were matched by tumor size and location (one group of tumors from patients who survived at least 15 years free of metastatic melanoma after enucleation and one group of tumors from patients who died of metastatic melanoma). A matched case-control analysis indicates that the presence of at least one closed vascular loop in a uveal melanoma is the most significant vascular pattern associated with death from metastatic melanoma after enucleation. Closed loops are associated with other histologic features that are predictive of an unfavorable outcome after enucleation: epithelioid cells and mitotic figures. In this preliminary study the formation of closed vascular loops is a marker of tumor progression in ciliary body and choroidal melanomas.

Follow-up rates are presented as a percentage but the method of calculation is seldom discussed. Determining a follow-up rate begins with identifying the numerator and denominator used in the calculation. Four methods of calculating follow-up rate after surgical treatment for weight reduction were studied. Method 1 follow-up rate, 91.2%, was calculated using patients with at least one follow-up contact as the numerator (6169) and the number of primary operations performed as the denominator (6764). Method 2 calculated patient contact on or beyond a specific time point: 65.9% for >/= 6 months (4232/6424), >/= 1 year (y) = 52.1% (3111/5977), >/= 2 y = 29.8% (1455/ 4890), >/=3y=18.8% (710/3784), >/=4y=12.5% (331/ 2643). Follow-up calculated using method 3 determined patient contact within specific time points: 0-1 y = 89.7% (6064/6764), 1-2 y = 45.8% (2739/5977), 2-3 y = 23.0% (1124/4890), 3-4 y=13.9% (526/3784), 4-5y=11.3% (298/2643). Method 4 studied patient contact within time points according to ASBS guidelines. Rates for method 4 were: 0-6 months = 58.8% (11,938/20,292), 6-12 months = 36.7% (4717/12,848), 1-2 y = 45.8% (2739/5977), 2-3 y = 23.0% (1124/4890), 3-4 y = 13.9% (52613784). Results using these four methods of calculation emphasize the need to standardize follow-up rate before operative comparisons can be made.

Assisted Reproductive Technology (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 procedures 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). This report presents the most recent national data and state-specific results.2006.In 1996, CDC initiated data collection regarding ART procedures performed in the United States, as mandated by the Fertility Clinic Success Rate and Certification Act of 1992 (FCSRCA) (Public Law 102-493 [October 24, 1992]). Beginning with 2004, CDC has contracted with Westat, Inc., a statistical survey research organization, to obtain data from ART medical centers in the United States. Westat, Inc., maintains the National ART Surveillance System (NASS), CDC's web-based data collection system.In 2006, a total of 138,198 ART procedures were reported to CDC. These procedures resulted in 41,343 live-birth deliveries, and 54,656 infants. ART procedures are categorized into four major procedure types: procedures that used embryos from freshly fertilized eggs (fresh embryos) from the patient's eggs (72%); procedures that used thawed embryos from the patient's eggs (16%); procedures that used fresh embryos from donor eggs (8%); and procedures that used thawed embryos from donor eggs (4%). Overall, 44% of ART transfer procedures resulted in a pregnancy, and 36% in a live-birth delivery (delivery of one or more live-born infants). Live-birth rates were generally higher among ART procedures that used fresh embryos from donor eggs (54%) than among other types. The highest numbers of ART procedures were performed among residents of California (18,886); New York (13,259); Illinois (9,594); New Jersey (9,237); and Massachusetts (8,305). All five states reported the highest number of live-birth deliveries as a result of ART. Of 54,656 infants born through ART, 48% were multiple-birth deliveries. The risk for a multiple-birth delivery was highest for women who underwent ART transfer procedures that used fresh embryos from either donor eggs (39%) or their own eggs (31%). Approximately 1% of U.S. infants born in 2006 were conceived through ART. Those infants accounted for 18% of multiple births nationwide. Approximately 9% of ART singletons, 57% of ART twins, and 96% of ART triplets or higher-order multiples were low birthweight. Similarly, 14% of ART singletons, 65% of ART twins, and 97% of ART triplets or higher-order multiples were born preterm.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 associated with adverse maternal and infant outcomes (e.g., placenta previa, preterm delivery, cesarean delivery, low birthweight, and infant mortality). This risk varied according to the patient's age, the type of ART procedure performed, the number of embryos available for transfer to the uterus, the number transferred, and the day of transfer (day 3 or 5).ART-related multiple births represent a sizable proportion of all multiple births nationwide and in selected states. To minimize the adverse maternal and child health effects associated with multiple pregnancies, ongoing efforts to limit the number of embryos transferred in each ART procedure should be continued and strengthened. Adverse maternal and infant outcomes (e.g., low birthweight and preterm delivery) associated with ART treatment choices should be explained thoroughly when counseling patients considering ART.

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 of 1992 (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 procedures 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).2004.In 2004, CDC contracted with a statistical survey research organization, Westat, Inc., to obtain data from ART medical centers in the United States. Westat, Inc., maintains CDC's web-based data collection system called the National ART Surveillance System.In 2004, a total of 127,977 ART procedures were reported to CDC. These procedures resulted in 36,760 live-birth deliveries and 49,458 infants. Nationwide, 74% of ART procedures used freshly fertilized embryos from the patient's eggs, 15% 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 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 that used freshly fertilized embryos from donor eggs (51%). The highest numbers of ART procedures were performed among residents of California (17,303), New York (11,123), Illinois (9,306), Massachusetts (8,906), and New Jersey (8,513). These five states also reported the highest number of infants conceived through ART. Of 49,458 infants born through ART, 50% were born in multiple-birth deliveries. The multiple-birth risk was highest for women who underwent ART transfer procedures that used freshly fertilized embryos from either donor eggs (40%) or their own eggs (33%). Approximately 1% of U.S. infants born in 2004 were conceived through ART. Those infants accounted for 18% of multiple births nationwide. Approximately 9% of ART singletons, 56% of ART twins, and 95% of ART triplets or higher-order multiples were low birthweight. The percentages of ART infants born preterm were 15% among singletons, 64% among twins, and 98% among triplets or higher-order multiples.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, the day of embryo transfer (day 3 or day 5), and embryo availability.ART-related multiple births represent a sizable proportion of all multiple births nationwide and in selected states. To minimize the adverse maternal and child health effects that are associated with multiple pregnancies, ongoing efforts to limit the number of embryos transferred in each ART procedure should be continued and strengthened. Adverse maternal and infant outcomes (e.g., low birthweight and preterm delivery) associated with ART treatment choices should be explained fully when counseling patients who are considering ART.

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).2003.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.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.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).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.

Objective: To assess associations between assisted reproductive technology (ART) and adverse maternal and infant outcomes, with an emphasis on singletons. Methods: We linked data from the US ART surveillance system with Massachusetts live birth-infant death records data for resident births in 1997–1998 and compared births conceived with ART (N = 3316) with births not conceived with ART or infertility medications (N = 157,066) on: maternal chronic conditions, pregnancy complications, labor and delivery complications, and perinatal and infant outcomes. Results: Overall, ART was strongly associated with numerous adverse outcomes. The magnitude was reduced for several outcomes when analyses were limited to singletons. After further exclusion of maternal subsets with rare ART births (maternal age

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).2002.: 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.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.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).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.

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).2001.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.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 ofor =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 agedor =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.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).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 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).2000.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.In 2000, a total of 25,228 live-birth deliveries and 35,025 infants resulting from 99,629 ART procedures were reported to CDC from 383 medical centers that performed ART in the United States and U.S. territories. Nationally, 75,516 (76%) of ART treatments were freshly fertilized embryos using the patient's eggs; 13,312 (13%) were thawed embryos using the patient's eggs; 7,919 (8%) were freshly fertilized embryos from donor eggs; and 2,882 (3%) were thawed embryos from donor eggs. The national live-birth delivery per transfer rate was 30.8%. The five states that reported the highest number of ART procedures were California (13,194), New York (11,239), Massachusetts (8,041), Illinois (7,323), and New Jersey (5,506). These five states also reported the highest number of live-birth deliveries and infants born as a result of ART. Overall, 47% of women undergoing ART-transfer procedures using freshly fertilized embryos from their own eggs were aged35 years; 23% were aged 35-37 years; 19% were aged 38-40 years; 7% were aged 41-42 years; and 4% were aged42 years. Among ART treatments in which freshly fertilized embryos from the patient's eggs were used, substantial variation in patient age, infertility diagnoses, history of past infertility treatment, and past births was observed. Nationally, live-birth rates were highest for women aged35 years (38%). The risk for a multiple-birth delivery was highest for women who underwent ART-transfer procedures using freshly fertilized embryos from either donor eggs (40%) or from their own eggs (35%). Among women who underwent ART-transfer procedures using freshly fertilized embryos from their own eggs, further variation by patient age and number of embryos transferred was observed. Of the 35,025 infants born, 44% were twins, and 9% were triplet and higher order multiples, for a total multiple-infant birth rate of 53%. Patient's residing in states with the highest number of live-birth deliveries also reported the highest number of infants born in multiple-birth deliveries.Whether an ART procedure was successful (defined as resulting in a pregnancy and live-birth delivery) varied according to different patient and treatment factors. Patient factors included the age of the woman undergoing ART, whether she had previously given birth, whether she had previously undergone ART, and the infertility diagnosis of both the female and male partners. Treatment factors included whether eggs were from the patient or a woman serving as an egg donor, whether the embryos were freshly fertilized or previously frozen and thawed, how long the embryos were kept in culture, how many embryos were transferred, and whether various specialized treatment procedures were used in conjunction with ART. ART poses a major risk for multiple births. This risk varied according to the patient's age, the type of ART procedure performed, and the number of embryos transferred. In addition, the increased risk for multiple births has a notable population impact in certain states.As use of ART and ART success rates continue to increase, ART-related multiple births are an increasingly important public health problem nationally and in many states. The proportion of infants born through ART in 2000 that were multiple births (53%) was substantially higher than in the general U.S. population during the same period. Data in this report indicate a need to reduce multiple births associated with ART. Efforts should be made to limit the number of embryos transferred for patients undergoing ART. In addition, continued research and surveillance is key to understanding the effect of ART on maternal and child health.

Objective To determine whether insurance coverage for ART is associated with transfer of fewer embryos and decreased risk of multiple births. Design Retrospective cohort study of a population-based sample of IVF procedures performed in six U.S. states during 1998. Setting Three states with mandated insurance coverage (Illinois, Massachusetts, and Rhode Island) and three states without coverage (Indiana, Michigan, and New Jersey). Participant(s) Seven thousand, five hundred sixty-one IVF transfer procedures in patients ≤ 35 years of age. Main outcome measure(s) Number of embryos transferred, multiple-birth rate, triplet or higher order birth rate, and triplet or higher order gestation rate. Result(s) A smaller proportion of procedures included transfer of three or more embryos in Massachusetts (64%) and Rhode Island (74%) than in the noninsurance states (82%). The multiple-birth rate in Massachusetts (38%) was less than in the noninsurance states (43%). The insurance states all had protective odds ratios for triplet or higher order births, but only the odds ratio (0.2) for Massachusetts was significant. This decreased risk in Massachusetts resulted from several factors, including a smaller proportion of patients with three or more embryos transferred, lower implantation rates when three or more embryos were transferred, and greater rates of fetal loss among triplet or higher order gestations. Conclusion(s) Insurance appears to affect embryo transfer practices. Whether this translates into decreased multiple birth risk is less clear.

BACKGROUND: Increasing use of assisted reproductive technology treatments has been associated with the current rise in multiple births in the USA. Embryo cryopreservation and subsequent thawed embryo transfer may favourably impact the multiple-birth risk by relieving some pressure that patients and providers may feel to transfer several embryos in a single cycle. The study objective was to examine both live-birth rates and multiple-birth risk in thawed cycles. METHODS: The authors used a population-based sample of 21 555 assisted reproductive technology procedures performed in US clinics in 1999 and 2000 that used thawed embryos derived from the patient's oocytes. RESULTS: Both patient age and the number of embryos transferred were independent predictors of live birth. Even among women aged 20-29 years, the transfer of three embryos resulted in an increase in the live-birth rate compared with cycles in which one or two embryos were transferred. This increase in success was accompanied by an increased multiple-birth risk. In all age groups up to 40 years, the transfer of just two embryos resulted in a multiple-birth risk of 16-17%. The multiple-birth risk increased with the number of embryos transferred. CONCLUSIONS: Patient age and the number of embryos transferred significantly affect live-birth and multiple-birth rates among women who use thawed embryos.

To examine trends in multiple births conceived using assisted reproductive technology (ART) in the United States between 1997 and 2000 and to estimate the proportion of all US multiple births attributable to ART use.We analyzed population-based data of 109 519 live-born infants who were conceived in the United States using ART and born between 1997 and 2000 and population-based data of 15 856 809 live-born infants who were delivered in the United States between 1997 and 2000. Multiple birth rates (the number of live-born infants delivered in multiple gestation pregnancies per 1000 live births) and the proportion of all US multiple births attributable to ART were evaluated.The twin rate for ART patients increased between 1997 and 2000, reaching 444.7 per 1000 live births in 2000, whereas the triplet/+ rate declined substantially from 134.3 to 98.7 per 1000 live births from 1997-2000. From 1997-2000, the proportion of multiple births in the United States attributable to ART increased from 11.2% to 13.6%, whereas the proportion attributable to natural conception decreased from 69.9% to 64.5%. In 2000, the proportion of triplet/+ births attributable to ART and to natural conception was 42.5% and 17.7%, respectively. The contribution of ART to multiple births increased substantially with maternal age, from 11.6% for triplet/+ infants born to women aged 20 to 24 to 92.8% for women aged 45 to 49 years.The contribution of ART to twin birth rates continues to increase, but the contribution of ART to triplet/+ birth rates has declined.

The increased risk of low birth weight associated with the use of assisted reproductive technology has been attributed largely to the higher rate of multiple gestations associated with such technology. It is uncertain, however, whether singleton infants conceived with the use of assisted reproductive technology may also have a higher risk of low birth weight than those who are conceived spontaneously.We used population-based data to compare the rates of low birth weight (less-than-or-equal 2500 g) and very low birth weight (1500 g) among infants conceived with assisted reproductive technology with the rates in the general population.We studied 42,463 infants who were born in 1996 and 1997 and conceived with assisted reproductive technology and used as a comparison group 3,389,098 infants born in the United States in 1997. Among singleton infants born at 37 weeks of gestation or later, those conceived with assisted reproductive technology had a risk of low birth weight that was 2.6 times that in the general population (95 percent confidence interval, 2.4 to 2.7). The use of assisted reproductive technology was associated with an increased rate of multiple gestations; however, its use was not associated with a further increase in the risk of low birth weight in multiple births. Among twins, the ratio of the rate of low birth weight after the use of assisted reproductive technology to the rate in the general population was 1.0 (95 percent confidence interval, 1.0 to 1.1). Infants conceived with assisted reproductive technology accounted for 0.6 percent of all infants born to mothers who were 20 years of age or older in 1997, but for 3.5 percent of low-birth-weight and 4.3 percent of very-low-birth-weight infants.The use of assisted reproductive technology accounts for a disproportionate number of low-birth-weight and very-low-birth-weight infants in the United States, in part because of absolute increases in multiple gestations and in part because of higher rates of low birth weight among singleton infants conceived with this technology.

Multiple birth, which is associated with adverse fetal, infant, and maternal outcomes, is increasingly related to the use of in vitro fertilization (IVF). Among women undergoing IVF who use their own eggs, greater maternal age is associated with decreased risk of multiple birth; using donor eggs from younger women may negate this age effect. Data from 6,936 IVF procedures performed in the United States in 1996-1997 on women aged 35-54 years who used donor eggs were analyzed to assess the effect of maternal age, number of embryos transferred, and cryopreservation of extra, nontransferred embryos (an indicator of higher embryo quality) on risk of multiple birth. Greater maternal age did not decrease multiple-birth risk. Rates of multiple birth were related to number of embryos transferred and whether extra embryos had been cryopreserved, and they were high compared with those of IVF patients the same age who had used their own eggs. Among women who had extra embryos cryopreserved, transferring more than two embryos increased multiple-birth risk, with no corresponding increase in the chance for a livebirth. These results highlight the need to consider the age of the donor and embryo quality when making embryo transfer decisions involving use of donor eggs.

Objective: To determine the cumulative probabilities over 14 y of requesting information on sterilization reversal and of obtaining a reversal and to identify risk factors observable at sterilization for both measures of regret. Design: The U.S. Collaborative Review of Sterilization, a prospective cohort study. Setting: Fifteen medical centers in 9 cities. Patient(s): 11,232 women. Main Outcome Measure(s): Cumulative probabilities of requesting information on reversal and undergoing reversal. Result(s): The 14-y cumulative probability of requesting reversal information was 14.3% (95% confidence interval [CI], 12.4%–16.3%). Among women aged 18 to 24 y at sterilization, the cumulative probability was 40.4% (95% CI, 31.6%–49.2%). Women aged 18 to 24 y were almost 4 times as likely to request reversal information as were women ≥30 years of age (adjusted rate ratio [RR], 3.5; 95% CI, 2.8–4.4). Number of living children was not associated with requesting reversal information. The overall cumulative probability of obtaining reversal was 1.1% (95% CI, 0.5–1.6). Younger women (18 to 30 y) were more likely to obtain reversal (RR, 7.6; 95% CI, 3.2–18.3). Conclusion(s): Women who were sterilized at a young age had a high chance of later requesting information about reversal, regardless of their number of living children.

ContextTo maximize birth rates, physicians who perform in vitro fertilization (IVF) often transfer multiple embryos, but this increases the multiple-birth risk. Live-birth and multiple-birth rates may vary by patient age and embryo quality. One marker for embryo quality is cryopreservation of extra embryos (if embryos are set aside for cryopreservation, higher quality embryos may have been available for transfer).ObjectiveTo examine associations between the number of embryos transferred during IVF and live-birth and multiple-birth rates stratified by maternal age and whether extra embryos were available (ie, extra embryos cryopreserved).Design and SettingRetrospective cohort of 300 US clinics reporting IVF transfer procedures to the Centers for Disease Control and Prevention in 1996.SubjectsA total of 35,554 IVF transfer procedures.Main Outcome MeasuresLive-birth and multiple-birth rates (percentage of live births that were multiple).ResultsA total number of 9873 live births were reported (multiple births from 1 pregnancy were counted as 1 live birth). The number of embryos needed to achieve maximum live-birth rates varied by age and whether extra embryos were cryopreserved. Among women 20 to 29 years and 30 to 34 years of age, maximum live-birth rates (43% and 36%, respectively) were achieved when 2 embryos were transferred and extra embryos were cryopreserved. Among women 35 years of age and older, live-birth rates were lower overall and regardless of whether embryos were cryopreserved, live-birth rates increased if more than 2 embryos were transferred. Multiple-birth rates varied by age and the number of embryos transferred, but not by whether embryos were cryopreserved. With 2 embryos transferred, multiple-birth rates were 22.7%, 19.7%, 11.6%, and 10.8% for women aged 20 to 29, 30 to 34, 35 to 39, and 40 to 44 years, respectively. Multiple-birth rates increased as high as 45.7% for women aged 20 to 29 years and 39.8% for women aged 30 to 34 years if 3 embryos were transferred. Among women aged 35 to 39 years, the multiple-birth rate was 29.4% if 3 embryos were transferred. Among women 40 to 44 years of age, the multiple-birth rate was less than 25% even if 5 embryos were transferred.ConclusionsBased on these data, the risk of multiple births from IVF varies by maternal age and number of embryos transferred. Embryo quality was not related to multiple birth risk but was associated with increased live-birth rates when fewer embryos were transferred.

To date, longitudinal weight loss analyses (curve-fitting) have been complicated by non-linear weight patterns, incomplete follow-up, and varied follow-up times. Therefore, the cross-sectional design (one time point survey) was chosen to study predictors of weight loss at yearly postoperative time intervals (+/- 6 months). Mean values for the initial cohort of 7,540 patients were: age 37.4 years (+/- 9.4), weight 124.0 kg (+/- 25.5), height 165.4 cm (+/- 8.5). Females comprised 87.7% of the data set. Follow-up was 62.5% at year one, 32.0% at year 2, 20.6% at year 3, and 15.4% at year 4. The multiple regression model used included 20 explanatory variables and was performed separately for four yearly time points. Only operative weight, initial visit height, age, and operative type were consistent predictors of weight loss (p0.05) at all time points examined and accounted for 40-50% of weight loss variation.