Long-term effects of the Diabetes Prevention Program interventions on cardiovascular risk factors: a report from the DPP Outcomes Study.

AIMS: Whether long-term cardiovascular risk is reduced by the Diabetes Prevention Program interventions is unknown. The aim of this study was to determine the long-term differences in cardiovascular disease risk factors and the use of lipid and blood pressure medications by the original Diabetes Prevention Program intervention group. METHODS: This long-term follow-up (median 10 years, interquartile range 9.0-10.5) of the three-arm Diabetes Prevention Program randomized controlled clinical trial (metformin, intensive lifestyle and placebo), performed on 2766 (88%) of the Diabetes Prevention Program participants (who originally had impaired glucose tolerance), comprised a mean of 3.2 years of randomized treatment, approximately 1-year transition (during which all participants were offered intensive lifestyle intervention) and 5 years follow-up (Diabetes Prevention Program Outcomes Study). During the study, participants were followed in their original groups with their clinical care being provided by practitioners outside the research setting. The study determined lipoprotein profiles and blood pressure and medication use annually. RESULTS: After 10 years' follow-up from Diabetes Prevention Program baseline, major reductions were seen for systolic (-2 to -3) and diastolic (-6 to -6.5 mmHg) blood pressure, and for LDL cholesterol (-0.51 to -0.6 mmol/l) and triglycerides (-0.23 to -0.25 mmol/l) in all groups, with no between-group differences. HDL cholesterol also rose significantly (0.14 to 0.15 mmol/l) in all groups. Lipid (P = 0.01) and blood pressure (P = 0.09) medication use, however, were lower for the lifestyle group during the Diabetes Prevention Program Outcomes Study. CONCLUSION: Overall, intensive lifestyle intervention achieved, with less medication, a comparable long-term effect on cardiovascular disease risk factors, to that seen in the metformin and placebo groups.

Combination treatment with estrogen and calcitriol in the prevention of age-related bone loss.

Estrogen deficiency and declining calcium absorption due to reduced calcitriol levels or intestinal resistance to calcitriol, are important factors in the pathogenesis of age-related bone loss. The main objective of this study was to examine the effect of estrogen and 1,25-dihydroxyvitamin D therapy given individually or in combination on bone loss in elderly women. Four hundred eighty-nine elderly women with normal bone density for their age, aged 65-77 yr, were entered into a randomized double blind, placebo-controlled trial. Women were randomized to one of four groups: conjugated estrogens (0.625 mg, daily) to women without a uterus (estrogen replacement therapy) plus medroxyprogesterone acetate (2.5 mg, daily) to women with a uterus (hormone replacement therapy), calcitriol (0.25 microg twice daily), a combination of hormone replacement therapy/estrogen replacement therapy plus calcitriol, or placebos for 3 yr. The primary outcome was the change in bone mineral density of the femoral neck and spine. In the intent to treat analysis, hormone therapy (hormone replacement therapy/estrogen replacement therapy) produced a mean (+/-1 SD) increase in bone mineral density of 2.98% (+/-5.45%) at the femoral neck (P < 0.0001) and 4.36% (+/-6.42%) at the spine (P < 0.0001). There were parallel increases in total hip and trochanter bone mineral density. Calcitriol increased bone mineral density 0.10% (+/- 4.27%) at the femoral neck (P = 0.57) and 1.65% (+/- 4.83%) at the spine (P < 0.0124). The combination of hormone replacement therapy/estrogen replacement therapy + calcitriol increased bone mineral density 3.80% (+/-4.95%) at the femoral neck (P < 0.001), 4.91% (+/-6.0%) at the spine (P < 0.0001), and parallel changes at the total hip and trochanter. All three treatment groups differed significantly from placebo at the spine and for the hormone replacement therapy/estrogen replacement therapy groups at the femoral neck, spine, total hip and trochanter. There were no significant differences between combination therapy and hormone replacement therapy/estrogen replacement therapy alone on bone mineral density at any site in the intent to treat analysis. In a secondary analysis of the effect in women who were adherent to treatment, calcitriol had a more significant effect on spine (P = 0.003) and total hip (P = 0.004). The increase in bone mineral density in the adherent groups of women was always higher compared with the intent to treat groups. Combination therapy compared with hormone replacement therapy/estrogen replacement therapy alone produced a significantly greater response in trochanter (P = 0.007) and total hip bone mineral density (P = 0.0017). In summary, hormone replacement therapy/estrogen replacement therapy alone and in combination with calcitriol therapy was highly effective in reducing bone resorption and increasing bone mineral density at the hip and other clinically relevant sites in a group of elderly women, with normal bone density for their age. Calcitriol was effective in increasing spine bone mineral density. In the adherent women, combination therapy with hormone replacement therapy/estrogen replacement therapy and calcitriol increased bone mineral density significantly more in the total hip and trochanter than did hormone replacement therapy/estrogen replacement therapy alone.

Conducting randomized, controlled trials. Experience with the dysfunctional uterine bleeding intervention trial.

OBJECTIVE: To conduct a randomized, controlled trial (RCT) to examine issues associated with therapeutic alternatives to standard hysterectomy for women with dysfunctional uterine bleeding. STUDY DESIGN: Participants were to be randomly assigned to one of three treatment groups: hysterectomy, endometrial ablation and medical management. Recruitment was targeted at 375 women. RESULTS: Despite multiple recruitment strategies, recruitment was weak, with only five women enrolled after six months. Providers and women screened for eligibility often expressed discomfort with randomization. The protocol was amended to an elective treatment cohort design with a randomization component. Recruitment improved, with 37 women enrolled after four months. CONCLUSION: The success of RCTs may be affected by multiple factors. Acceptance of the protocol by patients and providers is essential. The RCT may present providers with a conflict between the goals of research and of providing optimal individualized care. Thus, RCTs may not always be appropriate for studies designed to examine best treatments in clinical practice, and nonrandomized designs may provide appropriate alternatives in some cases.

Self-administered joint counts and standard joint counts in the assessment of rheumatoid arthritis. MIRA Trial Group. Minocycline in RA.

OBJECTIVE: To determine the comparability of a text to a mannequin format for the assessment of joint counts (JC) among patients with rheumatoid arthritis (RA) participating in a randomized clinical trial (RCT). METHODS: A subgroup of patients participating in the MIRA (Minocycline in RA) RCT completed self-administered JC and joint scores (JS), which were compared to those of a trained assessor. RESULTS: JC and JS data were consistently higher for the patient than for the assessor. Higher correlations were obtained for JC than for JS. CONCLUSION: Our data suggest JC can be used in the context of clinical trials or in the clinical setting, but are not interchangeable with trained assessor JC.

Calciotropic hormones and bone markers in the elderly.

There is a lack of substantial data on changes in calciotropic hormones and bone markers in elderly subjects living in North America. Parathyroid hormone (PTH), serum 25-hydroxyvitamin D (25(OH)D) and bone markers (serum osteocalcin and urine N-telopeptide), were measured in 735 Caucasian subjects (235 men and 500 women) aged 65-87 years. There was a significant increase in serum osteocalcin and urine N-telopeptide with age in men, and a significant increase in serum osteocalcin with age in women. Serum PTH and 25(OH)D showed no significant change with age in men or women. After adjusting for age, calcium intake, serum creatinine, season, and weight, mean serum PTH (p = 0.01), serum osteocalcin (p = 0.0001) and 24 h urine N-telopeptide (p = 0.0001) were higher in women than men, and mean serum 25(OH)D (p = 0.0001) and 24 h urine calcium (p = 0.0001) were higher in men than women. Serum PTH was correlated with serum osteocalcin in men and women, r = 0.24, r = 0.17, p < 0.001, but not with urine N-telopeptide. Serum PTH was inversely correlated with serum 25(OH)D (r = -0.25, r = -034,p < 0.001), and positively correlated with serum creatinine (r = 0.14, r = 0.17,p < 0.01) in men and women. The prevalence of serum 25(OH)D levels below 12 ng/ml was only 33% in females and 0.4% in men. Thus vitamin D deficiency was very uncommon in the U.S.A. compared with Europe. Although mean serum PTH was increased in the elderly, only 4-6% had PTH levels above the normal range. In summary, the increase in serum PTH in the elderly can be explained more by changes in vitamin D status than by declining renal function. These data also show significantly higher (p = 0.001) bone remodeling markers in women.

A cross sectional assessment of health status instruments in patients with rheumatoid arthritis participating in a clinical trial. Minocycline in Rheumatoid Arthritis Trial Group.

OBJECTIVE: To (1) validate the Short-Form Health Survey (SF-36) as a generic functional health status measure in patients with rheumatoid arthritis (RA); and (2) assess correlations between the SF-36 and other outcome measures used in the Minocycline in Rheumatoid Arthritis (MIRA) Trial. METHODS: We conducted a cross sectional analysis of the final visit outcome measures from the 48 week, multicenter, placebo controlled, double blind MIRA trial. Multitrait scaling analyses assessed convergent and discriminant validity and internal consistency reliability of the SF-36 in the study patients. Responses to comparable items on the SF-36 and modified Health Assessment Questionnaire (M-HAQ) regarding physical functioning were compared and questions from both instruments were also compared to other RA outcome measures. RESULTS: In patients with RA, the SF-36 had high internal consistency and reliability, high discriminant and high convergent validity. Moderate correlations were observed (r = -0.46 to -0.61, p < 0.01 in each case) for comparable items on the SF-36 and M-HAQ regarding dressing, walking, and bending. Joint tenderness score correlations with items on the M-HAQ and SF-36, and joint tenderness score correlations with the SF-36 scales were higher than for joint swelling scores. Physician and patient global assessments were most highly correlated (r = 0.58 and 0.66; p < 0.01, respectively) with the SF-36 bodily pain item. CONCLUSION: The SF-36 is a valid instrument for this RA population. The SF-36 correlates with the M-HAQ and the physician and patient global assessments. The usefulness of the SF-36 in measuring change in RA clinical trials requires testing in longitudinal studies.

Radiographic results from the Minocycline in Rheumatoid Arthritis (MIRA) Trial.

OBJECTIVE: To assess radiographically determined disease progression in patients in the Minocycline in Rheumatoid Arthritis (MIRA) Trial. METHODS: A double blind, randomized, multicenter, 48 week trial of oral minocycline (200 mg/day) or placebo in 6 clinical centers in the United States. Patients include 219 adults with active RA previously receiving limited treatment with disease modifying drugs. Posteroanterior films of the hands from baseline and final visits, blinded for sequence, were read for erosions and joint space narrowing by trained observers. Outcomes included rate of disease progression (change/month) and percentage of patients with progression from baseline, newly involved joints, and newly erosive disease. RESULTS: Using intent-to-treat analyses, progression rates for erosions (0.11 +/- 0.42 minocycline, 0.17 +/- 0.41 placebo; p = 0.47) and joint space narrowing (0.16 +/- 0.55 minocycline and 0.23 +/- 0.71 placebo; p = 0.14) were similar. (Power 43% to detect a 50% difference.) Newly erosive joints occurred more frequently in the placebo group (44 vs 32%; p = 0.08), not a statistically significant difference. CONCLUSION: Radiographic measurement of disease progression using 4 measures failed to show a significant difference between minocycline and placebo treatment, although for all methods there was a trend toward treatment benefit, consistent with reported clinical results. A one year trial duration, high measurement variability, and slow rate of radiographic progression in this cohort may explain the low power to detect a treatment effect. The measurement that denoted "newly involved" joints was most sensitive in detecting change. In future trials longer term assessment (minimum 2 years) of radiographic changes and further comparison of measures of disease progression are warranted.

Meaningful improvement criteria sets in a rheumatoid arthritis clinical trial. MIRA Trial Group. Minocycline in Rheumatoid Arthritis.

OBJECTIVE: To compare 3 sets of criteria for meaningful improvement in a rheumatoid arthritis (RA) clinical trial, and to evaluate the implications of these criteria sets for RA trial design. METHODS: Data were obtained from the Minocycline in Rheumatoid Arthritis (MIRA) trial (primary outcome measures: 50% improvement in joint tenderness and 50% improvement in joint swelling, based on joint scores). These MIRA data were evaluated against 1) the Paulus criteria (20% improvement in 4 of 6 measures: joint tenderness scores, joint swelling scores, physician's and patient's global assessments, erythrocyte sedimentation rate [ESR], and morning stiffness); and 2) the American College of Rheumatology (ACR) criteria (20% improvement in joint tenderness and joint swelling counts, and in 3 of 5 other measures: physician's and patient's global assessments, ESR, modified Health Assessment Questionnaire, and patient's pain assessment). The ACR criteria were modified using 3 of 4 remaining measures, since baseline pain assessment data were not available. RESULTS: Percentages of minocycline-treated patients versus placebo-treated patients showing meaningful improvement were as follows: by MIRA criteria, for joint tenderness, 56% versus 41% (P = 0.021), and for joint swelling, 54% versus 39% (P = 0.023); by Paulus criteria, 41% versus 28% (P = 0.040); and by ACR criteria, 44% versus 26% (P = 0.004). Both the modified ACR criteria and the Paulus criteria demonstrated a reduced placebo response rate. Compared with the MIRA criteria, the ACR criteria increased, and the Paulus criteria decreased, absolute between-group differences in improvement; however, both criteria sets increased relative percentages of patients showing improvement in the minocycline group versus the placebo group. Study design considerations indicated that application of the ACR criteria would reduce the required sample size. CONCLUSION: Different placebo response rates and treatment group differences were found using the 3 RA improvement criteria sets. These findings support the use of the ACR criteria for defining improvement in RA clinical trials.

HLA-DRB1 genes and disease severity in rheumatoid arthritis. The MIRA Trial Group. Minocycline in Rheumatoid Arthritis.

OBJECTIVE: To examine the effect of alleles encoding the "shared"/"rheumatoid" epitope on rheumatoid arthritis (RA) disease severity in patients who participated in the minocycline in RA (MIRA) trial. METHODS: Of 205 patients with a week-48 visit, blood was available for typing of HLA-DRB1 and HLA-DQB1 in 174 (85%) and successfully completed in 169 (82%). Baseline erosions were used to assess disease severity and new erosions at the last visit served as a proxy for progression. RESULTS: At baseline, there was no association between the presence of erosive disease or rheumatoid factor status and the dose of rheumatoid epitope (homozygous, heterozygous, none) or the specific alleles identified. At the final visit, a gradient was observed for the 3 allelic subgroups (and their gene doses) in the occurrence of new erosions among the Caucasian placebo-treated, but not the minocycline-treated, patients. A treatment group/HLA-DR4 epitope interaction was demonstrated in multivariate analyses. Approximately two-thirds of African-American patients did not have the rheumatoid epitope. CONCLUSION: HLA-DRB1 oligotyping may be useful in predicting the progression of disease in some Caucasian patients. Our study corroborates the infrequency of the epitope among African-American patients with RA.

Sodium excretion influences calcium homeostasis in elderly men and women.

This study was conducted to compare associations between urinary sodium and calcium in elderly men and women, overall and by level of calcium intake, and to examine associations between urinary sodium excretion and bone mineral density in the same population. Healthy men (n = 249) and women (n = 665) over age 65 y had measurements of 24-h urinary sodium and calcium and spine, hip, and whole-body bone mineral density. Urinary sodium and calcium excretion were significantly correlated in men (r = 0.42, P = 0.0001) and women (r = 0.26, P = 0.0001), but the regression coefficient was greater in men than in women (beta = 0.017 vs. 0.010, P = 0.007). Within each gender, associations between 24-h urinary sodium and calcium were similar and significant at intermediate and high calcium intakes but were not significant at very low intake levels. Urinary sodium was not correlated with bone mineral density. In conclusion, in healthy elderly men and women, urinary sodium and calcium excretion are linked at moderate and high dietary calcium intakes but not at low calcium intakes. For a given sodium excretion, elderly men excrete more calcium than women.

Minocycline in rheumatoid arthritis. A 48-week, double-blind, placebo-controlled trial. MIRA Trial Group.

OBJECTIVE: To assess the safety and efficacy of minocycline in the treatment of rheumatoid arthritis. DESIGN: A double-blind, randomized, multicenter, 48-week trial of oral minocycline (200 mg/d) or placebo. SETTING: 6 clinical centers in the United States. PATIENTS: 219 adults with active rheumatoid arthritis who had previous limited treatment with disease-modifying drugs. MEASUREMENTS: As the primary outcomes, 60 diarthrodial joints were examined for tenderness, and 58 joints were examined for swelling (hips excluded). Grip strength, evaluator's global assessment, morning stiffness, Modified Health Assessment Questionnaire, patient's global assessment, hematocrit, erythrocyte sedimentation rate, platelet count, and IgM rheumatoid factor levels were also assessed; radiographs of both hands and wrists were taken. RESULTS: 109 and 110 patients were randomly assigned to receive minocycline and placebo, respectively. At entry, demographic, clinical, and laboratory measurements were similar in both groups. Most patients had mild to moderate disease activity and some evidence of destructive disease. At the week 48 visit, 79% of the minocycline group and 78% of the placebo group continued to receive the study medication. At 48 weeks, more patients in the minocycline group than in the placebo group showed improvement in joint swelling (54% and 39%) and joint tenderness (56% and 41%) (P < 0.023 for both comparisons). The minocycline group also showed greater improvement in hematocrit, erythrocyte sedimentation rate, platelet count, and IgM rheumatoid factor levels (all P values < 0.001), and more patients receiving minocycline had laboratory values within normal ranges at 48 weeks. For the remaining outcomes, P values ranged from 0.04 to 0.76, all greater than the critical value of 0.005 (Bonferroni adjustment for multiple comparisons). The frequency of reported side effects was similar in both groups, and no serious toxicity occurred. CONCLUSIONS: Minocycline was safe and effective for patients with mild to moderate rheumatoid arthritis. Its mechanisms of action remain to be determined.

Quantitative and qualitative changes in lipids, lipoproteins, apolipoprotein A-I, and sex hormone-binding globulin due to two doses of conjugated equine estrogen with and without a progestin.

OBJECTIVE: To determine whether the quantitative and qualitative effects on lipoproteins differ between two doses of conjugated equine estrogen before and after progestin administration. METHODS: We randomized 103 postmenopausal women into a control group and into two groups receiving either 0.625 mg or 1.25 mg of conjugated equine estrogen for 4 months and then the same estrogen dose plus cyclic medroxyprogesterone acetate for 8 months. RESULTS: Both estrogen doses similarly lowered (P < .01) low-density lipoprotein (LDL) cholesterol and raised (P < .01) high-density lipoprotein (HDL) cholesterol, apolipoprotein A-I, triglyceride levels of all lipoproteins, and sex hormone-binding globulin capacity. Cyclic addition of the progestin reduced HDL cholesterol (P < .01) and apolipoprotein A-I (P < .05), but not LDL cholesterol in either estrogen group. A greater lowering of HDL cholesterol (P < .05) in response to the progestin was seen with the 0.625-mg dose of estrogen. Estrogen-induced triglyceride enrichment of HDL and LDL was not reversed by the progestin. CONCLUSION: The only significant quantitative difference in lipoprotein levels between the doses of conjugated equine estrogen before or after administration of medroxyprogesterone acetate was a greater decline in HDL cholesterol levels with the lower dose after 4 months of the progestin. This difference was not sustained over time. There were no differences between doses in the estrogen-induced triglyceride enrichment of lipoproteins, and these qualitative changes were not affected by the progestin.

Implications of maternal serum alpha-fetoprotein elevation caused by transabdominal and transcervical CVS.

Of 2882 women allocated to either transabdominal CVS (TA) or transcervical CVS (TC) at two large obstetric centres in Denmark, 2707 had blood samples drawn before and 30 min after CVS for maternal serum-alpha-fetoprotein (MSAFP) measurement. 2535 of these women had cytogenetically normal pregnancies and 2091 of them went on to have samples drawn at the 18-20 week follow-up. Post-procedure MSAFP values were correlated to the biopsy method used, with mean MSAFP values significantly higher after TA than TC, 33 and 15 kU/l, respectively (P < 0.001). Following TA procedures, 18 per cent of cases had feto-maternal transfusion higher than 0.1 ml; this occurred in only 5 per cent of TC cases. MSAFP levels were associated with spontaneous fetal loss in the TA group but not in the TC group. TC, however, was followed by more losses than TA. The post-CVS MSAFP value was positively correlated with the amount of villi aspirated. The difference in post-procedure elevation in MSAFP 30 min later (average 18 kU/l higher for TA than for TC) was not reflected in raised levels at the 18-20 week follow-up. Study medians at mid-trimester did not differ from reference group medians established from a group of singleton pregnancies with sonographically determined gestational age who did not experience invasive procedures and delivered normal infants. Our findings suggest that CVS does not compromise mid-trimester MSAFP for screening for neural tube defects (NTDs). Extremely high mid-trimester MSAFP values in the TC group could predict imminent loss.

[Randomized comparison of transabdominal, transcervical chorionic villi sampling and amniocentesis]. / Randomiseret sammenligning af transabdominal, transcervikal chorion villus biopsi og amniocentese.

The transabdominal chorionic villus sampling method was compared with the transcervical route and second trimester amniocentesis in a 3-winged randomised trial. Examination of 45 epidemiological variables showed the three procedure groups to be comparable at enrollment. In 3079 women at low genetic risk, we compared transabdominal with transcervical chorionic villus sampling and amniocentesis. The total fetal loss was 10.9%, 6.3% and 6.4% in the transcervical, transabdominal chorionic villus sampling groups and the amniocentesis group, respectively (p < 0.001). The two CVS procedures were compared in 2882 low and high genetic risk women with cytogenetically normal fetuses. Rates of unintended post-procedure loss were 3.7% and 7.7% for transabdominal CVS and transcervical CVS, respectively (p < 0.001), difference in rates 4.0%, 95% C.I. +2.3% to +5.8%. By a priori ultrasound scanning, more transcervical than transabdominal procedures (p < 0.001) were considered to be inaccessible for sampling. Our data indicate that transabdominal allows freer access to the placental site than transcervical sampling and is easier to adapt to than transcervical CVS. Women run comparable risks with transabdominal CVS and amniocentesis. Given the results of our study, transabdominal procedures remain the first choice for prenatal diagnosis and, since in our hands transcervical sampling entails an increased fetal risk, we have abandoned transcervical CVS in our two study centres.

Randomised comparison of amniocentesis and transabdominal and transcervical chorionic villus sampling.

We have compared three methods of prenatal diagnosis in two large obstetric centres in Denmark. Women were randomly assigned transabdominal (TA) chorionic villus sampling (CVS), transcervical (TC) CVS, or second-trimester amniocentesis (AC); women at high genetic risk were randomised between the two CVS groups only. Analysis of 45 epidemiological variables showed the three procedure groups to be similar at enrollment. All women were followed up until completion of pregnancy. Among 3079 women at low genetic risk total fetal loss rates were 10.9% for TC CVS, 6.3% for TA CVS, and 6.4% for AC (p < 0.001). More women had bleeding after the procedure in the CVS groups (p < 0.001), whereas more amniotic fluid leakage (p < 0.001) was reported after AC. No uterine infections occurred in any group. No case of oromandibular-limb abnormality was seen in the CVS groups, but 1 child in the AC group had aplasia of the right hand. The two CVS approaches were compared among 2882 women at low and high genetic risk who were found to have cytogenetically normal fetuses. Rates of unintentional loss after the procedure were 7.7% for TC CVS and 3.7% for TA CVS (p < 0.001; 95% Cl of difference 2.3-5.8%). At baseline ultrasound scanning after establishment of optimum sampling conditions, more TC than TA procedures (p < 0.001) were judged not to be feasible. We found that TA CVS allows better access to the placental site than TC sampling, is an easier skill to acquire, and has the potential that more villi can be aspirated when needed. The risk of fetal loss is similar after TA CVS and AC. However, losses after AC are at a later stage and are therefore more distressing. TA procedures remain the first choice for prenatal diagnosis. Since, in our hands, TC sampling carries a greater risk to the fetus, we have abandoned TC CVS in our two study centres.

A randomized comparison of transcervical and transabdominal chorionic-villus sampling. The U.S. National Institute of Child Health and Human Development Chorionic-Villus Sampling and Amniocentesis Study Group.

BACKGROUND: Chorionic-villus sampling is done in early pregnancy to obtain fetal cells for the prenatal diagnosis of genetic and chromosomal defects. Transcervical chorionic-villus sampling has been shown to be safe and effective in national trials. Recently, an alternative transabdominal technique has been suggested as potentially easier and safer. METHODS: From April 1987 through September 1989, we prospectively compared transcervical and transabdominal chorionic-villus sampling in 3999 women with singleton pregnancies in whom the risk of a genetically abnormal fetus was increased. Women between 7 and 12 weeks of gestation underwent ultrasonographic evaluation of placental and uterine position. Those with active vaginal infections, active bleeding, or cervical polyps were excluded. If the obstetrician thought either sampling procedure was acceptable, the woman was asked to consent to random assignment to one of the two procedures. Both groups were followed to determine the outcome of pregnancy and the rate of spontaneous fetal loss after chorionic-villus sampling. RESULTS: Among the 3999 women who entered the study, sampling was attempted in 3873 (97 percent), 1944 of whom had been assigned to undergo transcervical sampling and 1929 to undergo transabdominal sampling. Of these 3873 women, sampling was eventually successful in 3863. Sampling was successful after a single insertion of the sampling instrument in 94 percent of the transabdominal procedures and 90 percent of the transcervical procedures. Among the women with cytogenetically normal pregnancies who had sampling because of maternal age, the rate of spontaneous fetal loss through 28 weeks of pregnancy was 2.5 percent in the transcervical-sampling group and 2.3 percent in the transabdominal-sampling group (difference, 0.26 percent; 95 percent confidence interval, -0.5 to 1.0 percent). CONCLUSIONS: Transabdominal and transcervical chorionic-villus sampling appear to be equally safe procedures for first-trimester diagnosis of fetal abnormalities.

Chorionic mosaicism: association with fetal loss but not with adverse perinatal outcome.

Cytogenetic data from the United States NICHD collaborative study of chorionic villus sampling (CVS) were used to evaluate the clinical significance of chorionic mosaicism. The 10,754 patients with normal cytogenetic results were compared with 108 patients (1.0 per cent) with placental mosaicism and 181 patients (1.6 per cent) with pseudo-mosaicism. Of the pregnancies intended to continue, the pregnancy loss rate was significantly greater in patients with placental mosaicism than in the cytogenetically normal cohort (8.6 vs. 3.4 per cent, p less than 0.05). However, there was no difference in the frequencies of abruptio placenta, preterm labour or delivery, small-for-gestational-age newborns, pregnancy-induced hypertension, or neonates with Apgar scores less than 7.

Risk factors associated with transcervical CVS losses.

Factors found to be associated with pregnancy loss after transcervical CVS were race (higher for non-white), history of spontaneous abortion, unplanned pregnancy, history of spotting or bleeding during the pregnancy prior to CVS, and placental position (higher for fundal or lateral locations). Whether the increase in loss risk is due to the factor, per se, or the factor plus the CVS cannot be determined due to the lack of appropriate control data.