Gerard H. Zeilmaker

A prospective, randomized study of embryo transfer results after 3 or 5 days of embryo culture in in vitro fertilization

OBJECTIVES To compare the implantation rate of embryos after 3 and 5 days of IVF culture. DESIGN Prospective randomization of ET depending on the weekday of ovum pick-up (OPU). SETTING University Department of Endocrinology and Reproduction. PATIENTS All women entering an outclinic IVF program. INTERVENTIONS Two hundred thirty-three ETs performed on day 3 after OPU and 410 performed on day 5 were analyzed. When blastocysts with a clear inner cell mass were available, a maximum of two were replaced. RESULTS On day 3 after OPU, 60 pregnancies per 233 ET (26%) and on day 5, 102 pregnancies per 410 ET (25%) were induced. The average implantation rate per embryo was 13% and 12%, respectively. After subdivision according to embryo morphology, pregnancy rate per ET (n = 59) and implantation rate per embryo on day 3 with exclusively unfragmented embryos were 32% and 18%, respectively, not significantly different from ET (n = 73) exclusively with embryos containing > 0% and < 20% fragments: 27% and 12%. After transfer on day 5, when one or more cavitating embryos were available (n = 227), pregnancy and implantation rates were 40% and 23%, statistically different from ET on day 3. On day 5, ET exclusively with morula stages showing signs of starting blastulation (n = 26), pregnancy rate and implantation rate were 12% and 11%, respectively, from ET (n = 157) with embryos not reaching the latter stage: 6% and 3%. CONCLUSIONS Overall ET results after 3 and 5 days are comparable. After 5 days of culture, one to two embryos can be replaced with an average implantation rate of > 23% per embryo, minimizing the incidence of triplets.

Chromosomal aberrations in couples undergoing intracytoplasmic sperm injection: influence on implantation and ongoing pregnancy rates.

OBJECTIVE To determine the incidence of chromosomal aberrations in couples undergoing intracytoplasmic sperm injection (ICSI) and their influence on subsequent implantation and ongoing pregnancy rates. DESIGN Prospective study. SETTING Fertility center. PATIENT(S) Candidates for ICSI. INTERVENTION(S) Chromosomes were trypsin-banded in 2,280 patients. In all cases, 10 metaphases were karyotyped. Sex chromosome analysis was performed in 10 additional metaphases. When apparent chromosomal aberrations were detected, 100 metaphases were analyzed. MAIN OUTCOME MEASURE(S) Implantation and ongoing pregnancy rates in couples with a chromosomal disorder. RESULTS A chromosomal abnormality was demonstrated in 7.2% of all couples. Among the male partners, 4.48% had aberrations. Autosomal aberrations were present in 2.96%, and numerical or structural sex chromosome abnormalities were found in 1.52%. Among the female partners, numerical or structural abnormalities were documented in 9.79%. Only 2.32% of the female partners had autosomal structural abnormalities. Numerical or structural anomalies involving sex chromosomes were found in 7.47%. Implantation rates of 9.4% and 16.3% per embryo were observed in female partners with sex chromosome mosaicism and autosomal aberrations, respectively. In male partners, the respective rates were 3.8% and 23.1%. CONCLUSION(S) The incidence of chromosomal disorders in couples seeking ICSI treatment is considerable, especially minor mosaicism (<10%) of sex chromosomes in the female partners. Preliminary data indicate a low implantation rate in couples with minor mosaicism of sex chromosomes.

Blastocyst transfer in day-5 embryo transfer depends primarily on the number of oocytes retrieved and not on age

OBJECTIVE To analyze the effects of patient age and treatment cycle number on the occurrence of blastocyst transfer and subsequent implantation. DESIGN Prospective study. SETTING Department of endocrinology and reproduction. PATIENT(S) All 1,099 women had day-5 transfers after IVF or intracytoplasmic sperm injection treatment. INTERVENTION(S) All patients were checked for embryo development in vitro in consecutive day-5 transfer cycles. Two blastocysts or three lesser-developed embryos were transferred. MAIN OUTCOME MEASURE(S) Blastocyst formation rate or clinical pregnancy/implantation rate. RESULT(S) Of 929 patients in the first cycle, 545 (59%) had at least one blastocyst available for ET. Among 151 patients with a blastocyst in cycle 1, 77 developed one or more blastocysts in cycle 2 (51%). Fifty of 143 patients without a blastocyst in cycle 1 had at least one blastocyst in cycle 2 (35%). After subdivision of all day-5 ETs according to the first four cycles, the following implantation rates per embryo were found for ET with one or more blastocysts: cycle 1 (n = 545), 23%; cycle 2 (n = 264), 23%; cycle 3 (n = 110), 14%; and cycle 4 (n = 27), 12%, and with noncavitating embryos, respectively: (n = 384) 6%, (n = 193) 6%, (n = 94) 2%, and (n = 35) 3%. The negative correlation of the age of the woman on blastulation depended primarily on the number of oocytes retrieved. CONCLUSION(S) The blastocyst implantation rate decreased after cycle 2. Biologic ovarian age, rather than chronologic age, determines the frequency of blastocyst transfer or pregnancy rate.

The ovarian response as a predictor for successful in vitro fertilization treatment after the age of 40 years

OBJECTIVE To determine whether age or response to controlled ovarian hyperstimulation (COH) is a better predictor of IVF outcome in women > or = 40 years. DESIGN Retrospective analysis. SETTING A transport IVF program. PATIENT(S) For patients undergoing IVF treatment the correlation between treatment outcome and age and response to COH was analyzed using the data of 2,588 consecutive cycles. INTERVENTION(S) None. MAIN OUTCOME MEASURE(S) Pregnancy. RESULT(S) The incidence of poor ovarian response rises significantly with increasing age. Analysis of all cycles showed a significant decrease in clinical and ongoing pregnancy rate for women > or = 40 years. Analysis of cycles with a good ovarian response showed no statistically significant differences for these parameters between women > or = 40 years and those younger. A logistic regression analysis on pregnancy showed that ovarian response contributes more to the prediction of pregnancy than age. CONCLUSION(S) Patients aged > or = 40 years with a good response to COH have a good prognosis for IVF treatment. The age limit for acceptance of patients should not be set at 40 years. Instead, the response to COH can be used to predict candidates likely to have a successful IVF outcome.

In vitro fertilizing capacity of human spermatozoa with the use of zona-free hamster ova: interassay variation and prognostic value

The average fertilization percentage, with the use of zona-free hamster ova, of a donor group was 54% (range 11% to 100%). Nineteen sperm suspensions (24%) from a group of 79 infertile patients with semen abnormalities and 23 from a second group of 43 patients (54%) whose partner showed evidence of reproductive dysfunction, fertilized as well as spermatozoa from fertile donors. The interassay variation of the fertilization rates was found to be less than 20%. Spermatozoa from 10 patients with normal semen characteristics failed to penetrate. Six spontaneous conceptions were reported in the first group. Sperm from four of these patients had low fertilization percentages. This indicates that fertility prognosis cannot be made on the basis of a low in vitro fertilization percentage only. The fertilization rate negatively correlated with the duration of infertility. No positive assays were found after 6 years of infertility.

In Vitro Fertilizing Capacity of Fresh and Cryopreserved Human Spermatozoa: a Comparative Study of Freezing and Thawing Procedures

The capacity of human spermatozoa to penetrate zona-free hamster ova was used to investigate several methods of freezing and thawing sperm. No differences in postthaw sperm viability were obtained after cooling spermatozoa either with a complex egg yolk cryoprotective medium or glycerol. The in vitro fertilizing capacity of postthaw spermatozoa frozen with a moderate freezing rate was similar to that of spermatozoa frozen with a slow freezing rate. Significantly higher in vitro fertilization percentages were found when the spermatozoa were thawed at an environmental temperature of 22 degrees C (mean 51%) or 37 degrees C (mean 52%), as compared with spermatozoa thawed at 4 degrees C (mean 37%). Individual differences of in vitro fertilization percentages are discussed in relation to changes in motility. It is demonstrated that a high prefreeze in vitro fertilization percentage is no guarantee of a high postthaw fertilizing ability.

A comparison of in vitro fertilization results after embryo transfer after 2, 3, and 4 days of embryo culture

Embryo transfer results after a 2 to 4 day period of embryo culture were compared. Two thousand two hundred ninety-seven ETs, performed in 1991 and 1992, were analyzed. Ongoing pregnancy rates after 2, 3, or 4 days of embryo culture were 23.3%, 21.9%, and 26.4%, respectively. Multiple pregnancy rates were 36.2%, 38.8%, and 32.6% per ongoing pregnancy for the three groups, respectively. The implantation rate of 73 cavitating morulae on day 4 was surprisingly high (41%) compared with that of other developmental stages. Transfer after 4 days of culture gives the ability to recognize embryos with a very high implantation potential.

The influence of contamination of culture medium with hepatitis B virus on the outcome of in vitro fertilization pregnancies

Heat-inactivated human serum is added to the culture medium used for in vitro fertilization and other forms of assisted conception. Because one batch of pooled serum contained hepatitis B virus, an epidemic occurred among women participating in the treatment program. Seventy-nine women had serologic proof of hepatitis B infection. This incident gave the opportunity to study the effect of hepatitis B virus on pregnancy outcome and the newborn. The situation is unique because the preimplantation embryo was exposed to hepatitis B virus or the pregnancy was complicated by a (sub)clinical infection. Twenty-four women were or became pregnant while having an acute hepatitis B infection. Five pregnancies ended in abortion. The remaining 19 pregnancies ended in the birth of 24 children. No evidence for any harmful effect of exposure to hepatitis B virus in the embryonic or fetal period on the newborn could be found.

The influence of the interval between in vitro fertilization and embryo transfer and some other variables on treatment outcome

This prospectively randomized study compares the outcome of 434 ETs 48 to 52 hours after insemination (day 2) and 324 ETs 72 to 76 hours after insemination (day 3). The influence of the interval between insemination and ET was assessed, as well as that of the number of embryos transferred, embryo quality, and the presence of supernumerary embryos. The mean number of embryos transferred after 2 and 3 days was equal (2.9 embryos/ET). The pregnancy rates per ET were not significantly different (21.9% versus 23.5%), but a higher percentage of viable pregnancies was observed after ET on day 3 (88.2% against 69.5% following ET on day 2). Treatment outcome was positively correlated with the number of embryos transferred and the presence of supernumerary embryos.

Treatment policy after poor fertilization in the first IVF cycle.

Purpose:The chance of recurrence of poor fertilization in a second in vitro fertilization (IVF) cycle was assessed.Methods:Total fertilization failure was defined, and the relationship between the fertilization rate and the number of motile sperm cells per milliliter of semen was assessed. Patients with a total fertilization failure or poor fertilization (20% or less of the oocytes fertilized) were divided into three subgroups with different chances of fertilization and were followed in a subsequent IVF cycle.Results:The recurrence rate of total fertilization failure was high in all three groups (45–70%), and poor fertilization frequently occurred in the second cycle (50–75%).Conclusions:Poor fertilization frequently recurs in the second IVF cycle. The use of intracytoplasmic sperm injection could be considered after fertilization of 20% or less of oocytes in the first cycle, irrespective of the number of motile sperm cells per milliliter of semen.