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Biomedical subjects

G H Zeilmaker

Publications and source records attributed to G H Zeilmaker.

At least 19 recordsLinked to original sources
PubMed1999

Extraction of testicular sperm from previously cryopreserved tissue in couples with or without transport of oocytes and testicular tissue.

OBJECTIVE: To evaluate results of IVF and intracytoplasmic sperm injection (ICSI) with extraction of sperm from frozen-thawed testicular tissue. DESIGN: Retrospective follow-up study. SETTING: Fertility center. PATIENT(S): Thirty-five couples with transport of testicular tissue from a transport clinic and 125 local couples. INTERVENTION(S): Extraction of testicular sperm by maceration and enzymatic digestion from frozen-thawed testicular tissue before ICSI. MAIN OUTCOME MEASURE(S): Clinical pregnancy rate (PR) and implantation rate in couples with obstructive or nonobstructive azoospermia, motile or immotile sperm, and differing male serum FSH values. RESULT(S): The clinical PR per ET and implantation rate per embryo in couples with transport of testicular tissue were 40% and 18%, respectively, in cases of obstructive azoospermia and 37% and 26%, respectively, in cases of nonobstructive azoospermia. In the local couples, these rates were 42% and 19%, respectively, in cases of obstructive azoospermia and 18% and 10%, respectively, in cases of nonobstructive azoospermia. The implantation rates for ICSI were 26% with motile sperm and 11% with immotile sperm in the transport group and 16% and 8%, respectively, in the local group. Male serum FSH level did not clearly correlate with implantation rate. CONCLUSION(S): Clinical PR and implantation rate are not affected by transport of testicular tissue but are significantly affected by nonobstructive azoospermia and the use of immotile sperm. No major increase in chromosomal aberration or congenital malformation was noted in the offspring of this limited group.

Adolescent↗
PubMed1999

Retrieval, maturation, and fertilization of immature oocytes obtained from unstimulated patients with polycystic ovary syndrome.

PURPOSE: Our purpose was to determine whether immature oocytes could be retrieved under local anesthesia, whether these oocytes would mature and fertilize in vitro, and whether adequate endometrium development could be obtained after hormonal supplementation. METHODS: Ovum pick-up was performed under local anesthesia. Immature oocytes were cultured and inseminated. To prepare the endometrium, estradiolvalerate was administered in combination with micronized progesterone. RESULTS: Immature oocytes were obtained in all cases. Fifty-six percent (n = 30) of the oocytes developed into metaphase II (MII) after 48 hr of culture, and another 20% reached the MII stage by 72 hr. Normal fertilization was observed in only 10% of oocytes inseminated. No embryonic development occurred, and therefore embryo transfer was not performed in any of the patients. Endometrial microbiopsy was performed in all subjects and endometrial development was considered sufficient in eight patients. CONCLUSIONS: We collected immature oocytes from patients with polycystic ovary syndrome without general anesthesia. In vitro maturation of these oocytes seemed adequate but fertilization rates were poor. Sufficient endometrial quality was obtained after hormonal substitution.

Adult↗
PubMed1998

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.

Adult↗
PubMed1998

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.

Adult↗
PubMed1998

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.

Female↗
PubMed1998

Cumulative pregnancy rates and selective drop-out of patients in in-vitro fertilization treatment.

The validity of the cumulative pregnancy rate (CPR) calculated by life-table approach, obtained in a transport in-vitro fertilization (IVF) programme, was tested by the determination of possible influence of selective drop-out of patients with a poor treatment prognosis. A cohort of 1211 patients who had a first IVF cycle was followed, and the CPR after three IVF cycles was assessed. First cycles of patients who discontinued treatment after failed IVF, and of those who did not achieve a pregnancy but proceeded to a subsequent cycle, were compared for fertilization rate and for occurrence of prognosticators of poor treatment outcome: oocyte yield < or =2, and replacement of <2 embryos. The CPR after three cycles was 54.9%. No differences were found in the first and second cycles of patients who continued treatment and those who dropped out. Selective drop-out of patients with a poor treatment prognosis was not found. Therefore, although calculations of CPR using life-table analysis generally overestimate the real probability of pregnancy after successive IVF cycles, the calculated CPR after three IVF cycles gives a reliable indication of the chance of occurrence of a pregnancy for the population studied.

Adult↗
PubMed1997

A triplet pregnancy after in vitro fertilization is a procedure-related complication that should be prevented by replacement of two embryos only.

OBJECTIVE: To investigate whether the incidence and obstetric outcome of triplet pregnancies after IVF treatment justify strict limitation of the number of embryos to be replaced to two. DESIGN: Retrospective analysis. SETTING: A transport IVF program. PATIENT(S): All patients who had more than one embryo replaced. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Obstetric outcome, pregnancy. RESULT(S): High-order pregnancies occurred in 24 cases (23 triplets and 1 quadruplet). Three patients opted for selective embryo reduction (12.5%). Three triplet pregnancies spontaneously reduced to twins. Comparison of 18 triplets, reaching at least 20 weeks' gestation, with 54 twin pregnancies shows a higher perinatal mortality in the triplet group, causing 6 out of 18 patients to be confronted with at least one perinatal death. Triplets were born at a lower gestational age, had a lower birth weight, and a higher hospital admission rate of longer duration. Replacement of two, three, or four embryos did not lead to differences in pregnancy rates in the population studied. When a pregnancy occurred after replacement of three embryos, the risk of having a triplet pregnancy was 7.5%. CONCLUSION(S): The obstetric outcome of triplet pregnancies in our population indicates that triplet pregnancies after IVF treatment have to be prevented. Selective embryo reduction is acceptable for few patients only and can therefore not be seen as a solution. Replacement of three embryos results in triplet pregnancy in an unacceptably high percentage. Replacement of two embryos only gives acceptable IVF results and is the method chosen in the IVF program in Rotterdam to prevent triplet pregnancies.

Birth Weight↗
PubMed1996

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.

Blastocyst↗
PubMed1996

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.

Adult↗
PubMed1995

Minimal monitoring of ovarian hyperstimulation: a useful simplification of the clinical phase of in vitro fertilization treatment.

OBJECTIVE: To investigate the feasibility of IVF treatment with minimal monitoring during ovarian hyperstimulation. DESIGN: Retrospective analysis and prospective study with real-time control group. SETTING: Transport IVF program with transport clinic and satellite clinics. PATIENTS: One hundred consecutive IVF cycles monitored at a transport clinic and 100 concurrent consecutive cycles monitored at satellite clinics, using the same stimulation-monitoring protocol and resulting in oocyte aspiration, are compared retrospectively for the number of ultrasound (US) measurements carried out during monitoring and for results of IVF treatment. No patient selection took place. After introduction of a minimal monitoring protocol at a transport clinic, a prospective study was started comparing 100 minimal monitoring cycles at a transport clinic with 100 concurrent conventional monitoring cycles at satellite clinics, all resulting in oocyte aspiration. Patients entered the retrospective or prospective study only once. In all cases the same laboratory facility was used. Monitoring of ovarian hyperstimulation was done with US measurements only. Cycles were canceled for impending ovarian hyperstimulation syndrome (OHSS) when > 35 follicles were seen to develop during hyperstimulation. RESULTS: Retrospective analysis shows no difference for the average number of US measurements at transport and satellite clinics (2.8 +/- 0.9 and 3.0 +/- 1.0; mean +/- SD). No differences were found in the number of ongoing pregnancies obtained in the two groups: 22 and 18, respectively. One case of severe OHSS occurred in the satellite clinic group. Introduction of minimal monitoring at the transport clinic gives a significant reduction of the average number of US measurements at the transport clinic compared with satellite clinics, where conventional monitoring continued to be used (1.5 +/- 0.8 versus 2.8 +/- 0.9). Ongoing pregnancies at transport and satellite clinics numbered 33 and 26, respectively. In both groups one patient developed severe OHSS. Sixty-two percent of cycles at the transport clinic were monitored with one US measurement only. No cancellations for impending OHSS occurred during the study period. CONCLUSION: A large group of patients need only one US measurement during monitoring of ovarian hyperstimulation. Minimal monitoring gives a useful further simplification of the clinical phase of IVF treatment, without adverse effects on treatment outcome and incidence of OHSS.

Ambulatory Care Facilities↗
PubMed1995

Results of decentralized in-vitro fertilization treatment with transport and satellite clinics.

The results of in-vitro fertilization (IVF) treatments carried out in a university IVF centre are compared with those obtained following 15-40 min transportation of oocytes from a transport IVF clinic to the central IVF laboratory of the university centre. Moreover, treatment results following monitoring of ovarian stimulation in satellite clinics, combined with ovum retrieval at the transport clinic and transport of oocytes to the central IVF laboratory, are described. In a total of 5540 IVF treatment cycles, 24-26% of viable pregnancies per embryo transfer were found in the three groups. Comparison of results, obtained with the three different treatment modalities, showed no negative influences of transporting oocytes from transport clinic to IVF laboratory and of monitoring ovarian stimulation in satellite clinics. It is concluded that decentralization of the clinical phase of IVF treatment is possible. This leads to a more optimal use of existing laboratory facilities in large urban areas. It is stressed that good communication between satellite clinic, transport clinic and IVF laboratory is necessary for a decentralized IVF programme. To obtain good quality assurance, both the satellite clinic and the transport clinic must adhere to the same protocol.

Adult↗
PubMed1994

A randomized study of transcervical intrafallopian transfer of pronucleate embryos controlled by ultrasound versus intrauterine transfer of four- to eight-cell embryos.

OBJECTIVE: To establish the value of transcervical intrafallopian transfer of zygotes and the accuracy of fallopian cannulation. DESIGN: A prospective randomized study, comparing ultrasonically controlled transcervical intrafallopian transfer of zygotes with intrauterine transfer of cleaved embryos. SETTING: Department of IVF of the Rotterdam Academic Hospital. PATIENTS: One hundred forty-five patients with patent tubes entered the IVF program. MAIN OUTCOME MEASURE: Pregnancy rates in both groups and ultrasound (US) assessment during fallopian cannulation and ET. RESULTS: Transvaginal cannulation of the tube appears not to be sufficiently accurate when performed without US guidance. Catheter damage occurred in many cases. The previously reported superior implantation rate after intrafallopian transfer in comparison with intrauterine transfer could not be confirmed. CONCLUSIONS: Intrauterine transfer of cleaved embryos remains the method of choice in IVF.

Adult↗
PubMed1994

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.

Cells, Cultured↗
PubMed1993

Doubling the human menopausal gonadotrophin dose in the course of an in-vitro fertilization treatment cycle in low responders: a randomized study.

The effect of doubling the human menopausal gonadotrophin (HMG) dose in the same treatment cycle in which the ovarian response after 5 days of ovarian stimulation with 225 IU/day is 'low', has been evaluated in a prospective randomized study. Forty-six patients met the ultrasound and oestradiol criteria for enrollment in the study, one patient participated twice. In 22 patients treatment was continued with 225 IU HMG/day and in 25 patients the HMG dose was increased to 450 IU/day. No effect of doubling the HMG dose was found on the length of the ovarian stimulation, peak oestradiol values, number of follicles > or = 11 and > or = 14 mm in diameter respectively on ultrasound on the day of HCG administration, number of cancelled cycles, number of oocytes at follicular puncture and the number of patients with < or = 3 oocytes at retrieval. It is concluded that doubling the HMG dose in the course of an IVF treatment cycle is not effective in enhancing ovarian response in low responders. This is in accordance with current theories on follicular growth, which state that follicular recruitment occurs only in the late luteal and early follicular phase of the menstrual cycle.

Embryo Transfer↗