A regimen for obtaining mature human oocytes from donors for research into human fertilization in vitro

Oocyte donation for stem cell research

The future success of stem cell research by means of somatic cell nuclear transfer (SCNT) depends on a sufficient supply of human oocytes. However, oocyte donation presents certain risks for the donor, and concerns for women's welfare are rightly vocalized. At the same time, these risks are comparable with the risks faced by other healthy research subjects. Thus, research donation can withstand ethical scrutiny if it fulfils the same conditions as other research involving healthy human subjects. Specifically, this means that the benefits of the research project need to outweigh the harms, that risks must be minimized, that informed consent has to be guaranteed by averting undue inducement and the recruitment of vulnerable women and that donors can and should be reimbursed for their research participation.

In vitro fertilization program based on programmed cycles monitored by ultrasound only

OBJECTIVE

Programmed oocyte retrieval was performed in order to make the in vitro fertilization (IVF) program cheaper and work of the IVF team easier.

METHOD

In a group of 77 patients included in the IVF program, the menstrual cycle was modified with estrogen-progesterone contraceptive pills. For this reason, it was possible to start the stimulation protocol in all patients on the same day. The stimulation protocol was a combination of clomiphene (100 mg) for 5 days and HMG (150 IU) every other day. Cycles were monitored by ultrasound only.

RESULT

The implantation rate per embryo transfer was 22.4%. The number of embryos per embryo transfer was low (2.6 +/- 1.4) and eliminated the need for cryopreservation. Fertilization rate (82%) and embryo transfer rate (87%) were high. The take home baby rate was 14.3%.

CONCLUSION

Seventy percent of all punctures were performed in 3 days in the middle of the week. In our conditions, programmed oocyte retrieval is associated with significant economic benefits.

Comparison of stimulation with clomiphene citrate in combination with recombinant follicle-stimulating hormone and recombinant luteinizing hormone to stimulation with a gonadotropin-releasing hormone agonist protocol: a prospective, randomized study

OBJECTIVE

To compare IVF-ET outcome with a new stimulation protocol using clomiphene citrate (CC) with recombinant FSH and LH to stimulation with the standard long GnRH-a protocol.

DESIGN

Prospective randomized study.

SETTING

Outpatient infertility clinic in Vienna, Austria.

PATIENT(S)

Two hundred ninety-four infertile women undergoing IVF-ET; 154 IVF cycles stimulated with CC + recombinant FSH + recombinant LH (group A) and 140 cycles with long GnRH-a suppression + recombinant FSH (group B).

INTERVENTION(S)

Controlled ovarian hyperstimulation, egg retrieval, and ET.

MAIN OUTCOME MEASURE(S)

Cycle parameters (number of oocytes, fertilization, number of embryos) and outcome (pregnancy rate, cancellation rate, ovarian hyperstimulation syndrome [OHSS]).

RESULT(S)

Pregnancy rate per ET was 42.9% (implantation rate, 21.3%) in group A and 36.6% (17.4%) in group B. Cancellation rates were similar. The OHSS occurred in four cases (3%) in group A and 12 cases (10%) in group B.

CONCLUSION(S)

Stimulation with CC + recombinant FSH + recombinant LH leads to comparable pregnancy rates vs. the long protocol. With this new stimulation, less gonadotropins are used and there is less need for monitoring (lower cost for patient and clinic). The risk of OHSS is reduced as well. Therefore, this protocol should be regarded as the first-line treatment.

Clinical value of tests for assessing male infertility

The laboratory assessment of the male partner of an infertile couple is an important aspect of the overall investigation of that couple. The laboratory tests are designed essentially to determine whether (a) the semen samples contain adequate numbers of normal motile sperm, and the sperm are able (b) to migrate to the site of fertilization and (c) to fertilize oocytes. Within this framework, tests can be viewed as being either descriptive, in terms of describing the ejaculate and sperm, or assessing functional qualities of the sperm. Irrespective of the nature of the test, it must satisfy simple criteria, namely being reproducible and able to discriminate between the fertile and infertile populations reliably. External quality assurance programmes now exist for semen analysis and allied techniques to help laboratories to standardize their reporting and to identify the source of possible errors.

Programmed oocyte retrieval: clinical and biological effects of oral contraceptives administered before in vitro fertilization

We have prospectively compared two regimens of suppression of the hypothalamic-pituitary-ovarian axis by oral contraceptives (OCs) for 15 or 30 days and two ovarian stimulation protocols. The latent phase, which represents a period of ovarian insensitivity, was prolonged and directly correlated to the duration of suppression. Thirty days' suppression, compared with 15 days', resulted in the cancellation of more cycles and a lower fertilization and pregnancy percentage. No significant increase in either serum progesterone or luteinizing hormone was noted in suppressed cycles. It is concluded that if programming is desired, OCs should be used for the shortest period possible. The variation in the length of the follicular phase indicates that there is a different 'fixed' day for retrieval for each suppression-stimulation protocol and this day should be established prospectively.

Programmed gamete intrafallopian transfer (GIFT)

Thirty-three patients with unexplained infertility underwent a total of 42 programmed superovulation cycles in a gamete intrafallopian transfer (GIFT) programme. The date of oocyte retrieval was decided in advance and the cycle preceding oocyte collection was modified with norethisterone from mid-cycle until 14 days before the scheduled laparoscopy. This was followed by a fixed schedule superovulation regimen. Serum oestradiol, progesterone and luteinizing hormone were monitored and the data analysed retrospectively. A single ultrasound scan was performed on the day of laparoscopy to exclude ovulation. Thirty-eight GIFT procedures were performed, resulting in 11 (29%) clinical pregnancies of which four twin and four singleton pregnancies are continuing. There was a significant correlation between the oestradiol response pattern and the maturity of oocytes retrieved, the fertilization rate of supernumerary oocytes and the pregnancy rate. Programmed cycles may be conveniently combined with GIFT, and basic endocrinological monitoring can be used to identify cycles with a poor prognosis before laparoscopy.

Protocols for induction of ovulation. The concept of programmed cycles

Programmed oocyte retrieval which includes suppression of the hypothalamic-pituitary-ovarian axis by oral contraceptives or GnRH analogue and predetermined ("fixed") day for ovum pick-up has been demonstrated to yield a pregnancy rate that is comparable to that achieved by the conventional individualized approach to follicular maturation. We have prospectively compared two regimens of suppression (the pill and GnRH analogue) followed by two ovarian stimulation protocols (clomiphene citrate + human menopausal gonadotropin [CC + hMG] and pure follicle-stimulating hormone + human menopausal gonadotropin [pure FSH + hMG]). Sixteen patients were studied in each group. It was found that the latent phase, which represents a period of ovarian insensitivity, was prolonged and directly correlated to the duration of suppression, and that suppression with the GnRH analogue was associated with a shorter latent phase than that with the pill. Suppression with the pill for 30 days compared with 15 days resulted in a greater cancellation of laparoscopic oocyte retrieval, a lower fertilization rate, and a lower pregnancy rate. The numbers of oocytes recovered, fertilized, and cleaved were similar in both stimulation protocols. The use of the GnRH analogue for 30 days compared with 15 days was associated with a lower pregnancy rate, even though the number of oocytes that were recovered and fertilized were similar. Ovarian stimulation with pure FSH + hMG resulted in a shorter latent phase than did stimulation with CC + hMG, but the results of treatment with both protocols were similar. It is concluded that both the pill and GnRH analogue are acceptable means of manipulating the cycle and the day of oocyte retrieval. However, they should be used for the shortest periods possible because prolonged use is associated with some unwarranted effects. For each suppression-stimulation protocol there seems to be a different fixed day for retrieval that should be established prospectively.

Programmed ovulation induction and oocyte retrieval for in vitro fertilization

Forty-two patients underwent programmed ovulation induction for oocyte retrieval. They were treated in the preceding cycles with a progestagen, ethynodiol diacetate, at a dose of 2 mg twice daily. Two groups were defined based upon the stimulation protocol: Group A1 was stimulated with clomiphene citrate and human menopausal gonadotropin (hMG), and Group A2 with follicle-stimulating hormone (FSH) and hMG. They were compared to two randomized control groups of patients who received the same induction but were classically monitored. There was a high proportion of spontaneous ovulations in the programmed group (8/42) compared to the nonprogrammed group (0/42). There was a nonsignificant difference in the number of oocytes obtained or embryos replaced per cycle. Four pregnancies were obtained in the programmed group (24% per transfer), against 10 in the nonprogrammed patients (32% per transfer). The results of this method seem to be better using FSH for ovulation stimulation and a verification of the serum estradiol on the day of induction with human chorionic gonadotropin (hCG) and the following day (semiprogrammed method).

Human gene expression first occurs between the four- and eight-cell stages of preimplantation development

The earliest stages of development in most animals, including the few mammalian species that have been investigated, are regulated by maternally inherited information. Dependence on expression of the embryonic genome cannot be detected until the mid two-cell stage in the mouse, the four-cell stage in the pig (J. Osborn & C. Polge, personal communication), and the eight-cell stage in the sheep. Information about the timing of activation of the embryonic genome in the human is of relevance not only to the therapeutic practice of in vitro fertilization and embryo transfer (IVF), but more importantly for the successful development of techniques for the preimplantation diagnosis of certain inherited genetic diseases. We describe here changes in the pattern of polypeptides synthesized during the pre-implantation stages of human development, and demonstrate that some of the major qualitative changes which occur between the four- and eight-cell stages are dependent on transcription. In addition, it appears that cleavage is not sensitive to transcriptional inhibition until after the four-cell stage.

The use of mouse preimplantation embryos for quality control of culture reagents in human in vitro fertilization programs: a cautionary note

Mouse embryos with their zonae pellucidae intact are more resistant to suboptimal culture conditions than are zona-free embryos. This observation questions the general practice of using zona-intact preimplantation mouse embryos to monitor the quality of media and reagents used in human IVF programs.

A new approach to follicular stimulation for in vitro fertilization: programed oocyte retrieval

Programed oocyte retrieval was performed in a group of 35 patients undergoing in vitro fertilization (IVF) treatment. The date of follicular aspiration was decided several months in advance and the cycle prior to oocyte recovery was modified with a progestagen or an estrogen-progestagen contraceptive pill. This was followed by a fixed-schedule ovulation stimulation and induction regimen. Follicular growth was not monitored. Thirty-four of the 35 patients had follicular aspiration, and at least one embryo was obtained in 30 of them. The clinical pregnancy rate (excluding cryopreserved embryos) was 20% per IVF cycle, 21% per attempted oocyte retrieval procedure, and 23% per embryo transfer cycle. Programmed oocyte retrieval is a realistic option for follicular stimulation for IVF treatment and is associated with significant practical and economic benefits.

Programmed oocyte retrieval during routine laparoscopy and embryo cryopreservation for later transfer

Fixed-schedule ovulation induction and cryopreservation of the obtained embryos was performed in women undergoing a preliminary laparoscopy for infertility investigation before possible inclusion in an in vitro fertilization program. The cycle before follicular stimulation was modified by a progestogen or an estrogen-progestogen contraceptive pill. Ovarian inaccessibility precluded follicular aspiration in four of 34 patients but at least one oocyte was obtained in 29 of the remaining 30. Although fewer oocytes were obtained in these patients than in a control group undergoing in vitro fertilization treatment, one or more embryos were obtained in 22 patients in the study group. All embryos were frozen and to date 25 embryos from 17 patients have been thawed. Embryos have been placed in 16 of the 17 patients and six pregnancies have been initiated. Three are currently ongoing, one ectopic pregnancy was recorded, and two pregnancies were classified as "chemical." Programmed oocyte retrieval and embryo cryopreservation resulted in an extra chance of pregnancy in patients undergoing a laparoscopy for infertility investigation.

A comparison of fixed regimens for obtaining human cleaving oocytes for research purposes

A fixed schedule for ovarian stimulation and follicular aspiration, previously used in our department for research purposes, was modified in an attempt to increase the recovery and cleavage rates of the oocytes. Three different clomiphene regimens were used to stimulate the ovaries of normal volunteer women requesting laparoscopic sterilization (50 mg and 150 mg daily for 5 days, and 50 mg daily for 10 days). Oocytes were recovered from 83% of the aspirated follicles, i.e. 1.6 oocytes/patient: 65% of the oocytes cleaved after in-vitro fertilization and, on average, 1.0 cleaving egg was obtained per patient. There were no differences in the recovery and cleavage rates between the three clomiphene regimens. It is concluded that a sufficient number of cleaving embryos for research purposes can be generated with the present fixed regimen, which offers little inconvenience to the volunteers as the day of egg recovery can be predicted some time in advance.

Preparation of human spermatozoa for in vitro fertilization by isopycnic centrifugation on self-generating density gradients

A simple and rapid method is described for the retrieval of highly motile, morphologically normal spermatozoa from human semen. This method is a modification of a technique described previously and employs the process of isopycnic centrifugation of semen on self-generating Percoll density gradients. The procedure is carried out under sterile conditions and has no detectable deleterious effects on the fertilizing capacity of spermatozoa. Spermatozoa may be recovered from semen samples of widely differing quality and can be used successfully for in vitro fertilization (IVF). This technique may be useful not only for the preparation of spermatozoa for IVF and possibly for artificial insemination by husband (AIH) but also for the investigation and analysis of the causes of infertility associated with oligozoospermia.