Clinical Abortion Rate Research Articles

Over a decade of experience with preimplantation genetic diagnosis

The three respondents provide additional support for preimplantation genetic diagnosis (PGD) having the pivotal place it now has in prenatal genetic diagnosis: chromosomal abnormalities (e.g., unbalanced translocations), Mendelian disorders, and HLA typing for transfer of compatible, genetically normal, embryos. Transferring euploid embryos has decreased the clinical abortion rate and increased the implantation rate in assisted reproductive technologies (ART), but it has not necessarily improved the live-birth rate. Safer embryo biopsy, more extensive diagnostic efforts (i.e., microarray analysis), and more refined patient selection may be required before shifting from preselection of embryos based solely on morphological parameters to transfer of only aneuploidy-free embryos.

Luteal phase support using either Crinone ® 8% or Utrogest ®: results of a prospective, randomized study

The Crinone ® 8% preparation makes it possible to administer natural progesterone (90 mg) vaginally once daily for luteal phase support (LPS). Until now, no prospective, randomized studies have directly compared this new preparation with widely used Utrogest ® capsules, which were originally designed for oral administration but are used routinely as a vaginal preparation. A prospective, randomized study investigated 126 patients undergoing cycles of in vitro fertilization (IVF) and IVF/intracytoplasmic sperm injection (ICSI). Patients received either Crinone ® 8% ( n=73) vaginally once daily or two Utrogest ® capsules ( n=53) vaginally three times daily (600 mg). Clinical pregnancy rates were comparable (28.8 versus 18.9%), as were clinical abortion rates until 12 weeks of gestation (14.3 versus 10.0%) and clinical ongoing pregnancy rates (24.7 versus 17.0%) in the Crinone ® 8% and Utrogest ® groups, respectively. Forty-seven non-pregnant patients were randomly selected to answer questions regarding comfort during LPS. Crinone ® 8% had a clear advantage over Utrogest ® as it resulted in less vaginal discharge ( P<0.01) and fewer application difficulties ( P<0.05). Twenty patients familiar with the alternative preparation from a previous cycle also noted that Crinone ® 8% was easier to apply ( P<0.01) and less time consuming ( P<0.05) to use than Utrogest ®.

Outcome of pregnancies derived from assisted reproductive technologies: IVF versus ICSI.

To compare the course and outcome of in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) pregnancies. A retrospective study was conducted in a university-affiliated IVF unit with 200 patients who conceived in 1996-1997, 100 with ICSI and 100 with IVF. Data were retrieved from our prospectively created computerized database. In addition, all patients were interviewed by telephone, and the interviewing physician completed a detailed questionnaire. Findings for the IVF and ICSI pregnancies were compared. The main outcome measures were maternal age, implantation rate, early pregnancy complications, clinical abortion rate, multiple pregnancy delivery rate, gestational age at delivery, mode of delivery, and birth weight. In all, 238 children were born, including 104 singleton infants (45 IVF, 59 ICSI), 49 twin pairs (28 IVF, 21 ICSI), and 12 triplet sets (3 IVF, 9 ICSI). Statistically significant differences between the ICSI and IVF groups were noted for maternal age (31.3 +/- 4.4 vs. 33.4 +/- 4.8, respectively, P < 0.005) and clinical abortion rate (11% vs. 24%, respectively, P < 0.05). ICSI pregnancies in our series were characterized by a lower clinical abortion rate than IVF pregnancies, probably because of the mean younger age of the ICSI group.

Oocyte quality and treatment outcome in intracytoplasmic sperm injection cycles of polycystic ovarian syndrome patients.

Patients with polycystic ovarian syndrome (PCOS) have higher miscarriage rates. It is postulated that this is caused by a lower rate of mature oocytes, and a lower quality of embryos. Retrospectively we analysed 51 intracytoplasmic sperm injection (ICSI) cycles of 31 PCOS patients. These data were compared to age-matched controls (105 cycles) during the same period. All patients of both groups received gonadotrophin-releasing hormone (GnRH) agonists prior to gonadotrophin treatment. The rate of metaphase II oocytes (MII) was not different. However, the mean absolute number of normally fertilized oocytes was significantly higher in PCOS patients (5.00 versus 3.56, P < 0.01), due to a higher number of oocytes retrieved. More embryos were transferred by cycle in the PCOS group (2.69 versus 2.17, P < 0.05), with a higher cumulative embryo score. The overall and multiple pregnancy rate showed no differences and the clinical abortion rate was lower (21 versus 41.67%, P < 0.05) in the controls. Our findings demonstrate that negative factors unconnected to oocyte morphology must be present in PCOS patients. It is possible that only cytoplasmic, not nuclear, maturity is influenced in these patients.

The outcome of cryopreserved human embryos after intracytoplasmic sperm injection and traditional IVF.

Our objective was to analyze the outcome of cryopreserved embryos obtained after intracytoplasmic sperm injection (ICSI) and in vitro fertilization (IVF) in terms of survival rate, implantation rate (IR), total and clinical pregnancy rate (PR) in a retrospective, comparative study. Three hundred seventy-five IVF and 463 ICSI surnumerary cleaved embryos, frozen on Day 2 with 1,2-propanediol, were thawed. Thirty-two percent of the thawed IVF embryos survived and 11 pregnancies (8 clinical) were obtained from 68 transfers (16.1%). Fourty-seven percent of the ICSI embryos survived, with 19 pregnancies (18 clinical) from 116 transfers (16.4%). The IR was 8.5% (8/94) in IVF cycles and 10.8% (20/185) in ICSI cycles. A significantly better survival rate of ICSI embryos was observed but with no difference in PR, preclinical, and clinical abortion rate, or IR.

The effect of human menopausal gonadotrophin and highly purified, urine-derived follicle stimulating hormone on the outcome of in-vitro fertilization in down-regulated normogonadotrophic women

It has been suggested that the luteinizing hormone (LH) activity of human menopausal gonadotrophin (HMG) preparations used for ovarian stimulation in in-vitro fertilization (IVF) may have adverse effects on reproductive outcome. In the present prospective, randomized trial of 218 infertile couples this notion was investigated. A total of 114 women were treated with Pergonal (HMG group) and 104 with Fertinorm HP (HP-FSH group). The two groups were comparable with regard to duration of infertility, cause of infertility, age and number of previous IVF attempts and all had normal basal gonadotrophin concentrations before treatment was started. A standard hormonal treatment consisting of pituitary down-regulation with gonadotrophin-releasing hormone analogue (GnRHa) for 14 days starting on cycle day 21, followed by either HMG or highly purified follicle stimulating hormone (HP-FSH), three ampoules (225 IU) per day for 7 days, was used in all cases. The daily hormone dose was thereafter individualized according to the ovarian response. A maximum of two pre-embryos were transferred after 3 days of culture. Luteal support with progesterone (300 mg per day intravaginally) was used in all cases. Serum concentrations of oestradiol, FSH and LH were measured on days 1 and 8 of stimulation and on the day of oocyte retrieval. The mean number of days of stimulation, mean number of ampoules of HMG or HP-FSH used, mean total motile sperm count on the day of oocyte retrieval and mean numbers of oocytes retrieved (13.4 versus 13.7) or pre-embryos transferred (1.8 versus 1.8) were similar for both groups. Significantly (P < 0.05) more cycles in the HP-FSH group (17 = 16%) were cancelled due to complete failure of fertilization than in the HMG group (7 = 6%). The mean fertilization rate was significantly (P < 0.05) higher in the HMG group (56%) than in the HP-FSH group (50%), and significantly more transferable pre-embryos were obtained in the HMG than in the HP-FSH group (mean: 4.0 versus 3.2; P < 0.01). Serum hormone concentrations were similar to the two groups on stimulation day 1, but differed significantly with regard to FSH, LH and oestradiol on stimulation day 8. The clinical outcome was similar in the two groups, with an ongoing pregnancy rate (> 12 weeks of gestation) per started cycle of 33% in the HMG group and 29% in the HP-FSH group. The clinical abortion rates were similar (10 and 14%), and the implantation rate was 30% in each group. In conclusion, no detrimental effect of the LH activity of HMG on the clinical outcome of IVF in GnRHa down-regulated normogonadotrophic women was found. To the contrary, some beneficial effects of HMG on fertilization rates and pre-embryo development as compared with HP-FSH were demonstrated. These effects, as well as the differences in serum hormone concentrations during ovarian stimulation, may be caused by differences in LH content and/or in the composition of FSH isoforms of the HMG and HP-FSH preparations.

The applicability of the cumulative embryo score system for embryo selection and quality control in an in-vitro fertilization/embryo transfer programme.

The cumulative embryo score system involves three aspects of relevance in pregnancy achievement during in-vitro fertilization (IVF) and embryo transfer: cleavage rates, morphological qualities and the number of embryos transferred. The scores of 602 IVF/embryo transfer trials were calculated and analysed to determine the system's relationship to pregnancy rate, pregnancy outcome and the incidence of twin and triplet pregnancies. The system was also applied to cycles where endotoxins were either present in or absent from culture medium, in order to evaluate its validity in quality control analyses. Pregnancy rates were found to increase from 4%, with scores between 1 and 10, to 35% in the 41-50 group. The score of 20 was the criterion for separating patients into poor and good pregnancy prognosis groups (P = 0.00001). Biochemical abortions occurred more frequently with scores < 20 (P = 0.00978), but a similar relationship was not found in clinical abortion rates (P = 0.62206). Birth rates below and above a score of 20 (2.8 and 19.2%, respectively) differed significantly (P = 0.0005). The scores of twins overlapped extensively with those of singleton births, but those of all triplets were > 40. The system did not reflect a correlation between embryo quality and the presence of endotoxins in culture medium.

Pregnancy Complications and Short‐Term Follow‐Up of Infants Born After in Vitro Fertilization and Embryo Transfer (IVF/ET)

Two hundred and six pregnancies occurring after in vitro fertilization (IVF) and embryo transfer (ET) during a 7-year period in Göteborg were analysed with respect to pregnancy outcome. The clinical abortion rate was 26%, the rate of ectopic pregnancy was 10%, the rate of ongoing pregnancies beyond 24 weeks was 15%, and the rate of deliveries was 49% (n = 100). The hospital records of 98 women with the 100 deliveries resulting in 131 infants were studied. Multiple pregnancy occurred in 27%, including one quadruplet and two triplet pregnancies. Preterm birth occurred in 30% of all pregnancies and in 20% of singleton pregnancies. Thirty-four percent of the infants had a birth weight of less than 2500 g. The perinatal mortality was 46/1000, as estimated from the 24th week of pregnancy. The incidence of major malformation, 2.3%, was similar to that reported from studies in the general population. The first 100 infants born were followed up for 18 months to 8 years. Long-term sequelae were associated with immaturity and low birth weight. No problems during follow-up were disclosed in children who had had an uneventful neonatal period. It is concluded that IVF pregnancies are an obstetric risk group requiring special attention.

Intrauterine insemination: a European collaborative report.

This report summarizes the data collected in the European Collaborative Report on intrauterine insemination (IUI) with pretreated sperm. A questionnaire concerning methods and results of IUI was sent to European infertility clinics and evaluable data were obtained from 29 of these clinics. A total of 196 pregnancies was reported from a total of 20 clinics. Pregnancy rates per treatment cycle were on average 7.4% of all male infertility, 10.8% for infertility due to hostile cervical mucus and 12.9% for idiopathic infertility, giving an overall pregnancy rate per treatment cycle of 8.4%. The clinical abortion rate was on average 12.2%. The mean number of years of primary infertility in the patient group of the clinics reporting pregnancies was 4.8 years and the mean number of years of primary infertility in the patient group conceiving was 5.2 years. A total of 127 births was reported with a sex ratio (male/female) of 0.512. One congenital malformation was reported. In many clinics, treatment of male infertility with IVF or IUI gave comparable results per treatment cycle. No single factor in the procedure for performing IUI was identified accounting for the different pregnancy rates obtained in the clinics included in this study.

What is a pregnancy? A question for programs of in vitro fertilization

Pregnancy outcome in studies of normal reproduction and in programs of in vitro fertilization (IVF) is usually classified as "chemical beta-human chorionic gonadotropin (beta-hCG) abortion," "trimester abortion," and "term delivery." The distinction between a chemical beta-hCG abortion and a first-trimester abortion is not clearly stated in the literature, although such terms are commonly used. It is proposed that in programs of IVF pregnancy outcome be classified as "menstrual abortion," "preclinical abortion," "clinical abortion," or "viable pregnancy." Pregnancy outcome of 190 consecutive cycles induced by human menopausal gonadotropin/human chorionic gonadotropin in the program of IVF at Norfolk is compared with contemporary studies of pregnancy outcome in normal reproduction. The in vitro data indicate that the Norfolk program has recorded no menstrual abortions, a 33% preclinical and clinical abortion rate, and a viable pregnancy rate that approaches but does not equal the term delivery rate of normal reproduction. However, these results have been achieved by the transfer of multiple concepti, whereas normal reproduction depends on the fertilization of a single oocyte.