Experiences with the first 100 consecutive pregnancies achieved after in vitro fertilization and embryo transfer at the University Women's Hospital in Erlangen

As of March 31, 1985, 100 clinical pregnancies have been achieved since the program for extracorporeal fertilization was started in Erlangen. 531 (71%) of 768 follicular punctures resulted in an embryo transfer. The overall pregnancy rate is 13% with regard to the total number of laparoscopies and 19% with regard to the number of embryo transfer. The most effective stimulation proved to be the pure hMG regimen. Employing this protocol, we have achieved a clinical pregnancy rate after IVF and ET of 32% during the last 6 months. Oocyte recovery related to the number of patients is 97%, with laparoscopy being superior to ultrasonically guided puncture. The success rate is appreciably affected by both the number of transferred embryos and the atraumatic transfer technique. We question the rationale of supporting the luteal phase.

[Use of a rapid method of cryopreservation of bovine embryos for non-surgical transfer in transplantation practice]

The embryos were frozen and thawed in Cassou minipaillette by a rapid method. Embryos with cryoprotective agent (glycerol, 1.5 M) were placed directly into the freezing medium at the temperature of -6 to -7 degrees C, frozen after seedling at the temperature decrease by 0.3 to 0.5 degrees C per minute to the temperature of -32 degrees C and then transferred directly into liquid nitrogen. They were thawed in a bath warm 20 to 37 degrees C. After thawed the cryoprotective agent was evacuated in 1.1 M sucrose. The best-quality embryos were selected for freezing. Out of these 366 thawed so far, with average survival of 74.31%. The total of the 268 thawed embryos were transferred ipsilaterally, by a non-surgical method, to 190 synchronised heifers, out of which 105 (55.26%) got in calf. Rapid freezing method based on 1.5 M of glycerol and thawing at the presence of 1.1 M sucrose proved effective and suitable for practice, as not only sufficient reviviscence of embryos and their survival in womb are guaranteed, but also a substantial shortening of the freezing as well as thawing process.

Improved pregnancy rate in human in vitro fertilization with the use of a medium based on the composition of human tubal fluid

Significantly more mouse zygotes developed to blastocysts in culture in a medium formulated on the composition of human tubal fluid (HTF) than in modified Tyrode's medium (T6). In a randomized 2 X 2 factorial trial of human in vitro fertilization that compared the two media and culture under oil versus culture in loosely capped tubes, significantly more clinical pregnancies (30% of 60 transfers) were obtained with HTF medium than with T6 medium (11% of 53 transfers). Decreasing the K+ content of HTF medium to that present in T6 medium significantly decreased the number of mouse zygotes that developed in culture. Modifying Ca++ levels had no effect. It is therefore likely that the higher K+ content in HTF medium is primarily responsible for the superiority of HTF medium over T6 medium, but other differences in the composition of the two media could contribute to the results observed.

Reconstructive pelvic operations for in vitro fertilization

Lysis of adhesions, bilateral salpingectomy, and ovarian suspension were carried out in 54 normal ovulatory patients with long-standing infertility that was associated with severe pelvic adhesions after multiple laparotomies for reimplantation of the fallopian tubes, salpingostomy, lysis of adhesions, or severe endometriosis. Ovulation was induced in 39 patients after laparotomy for in vitro fertilization, with the use of human menopausal gonadotropin, pure follicle-stimulating hormone, and human chorionic gonadotropin. Oocyte retrieval by laparoscopy was accomplished in 37 patients, and embryo transfer was carried out in 36. Pregnancy after in vitro fertilization and embryo transfer occurred in 14 patients. Although severe adhesions recurred in four patients, a significant improvement was obtained after the procedure in the others.

Implantation, abortion, and birth after in vitro fertilization using the natural menstrual cycle or follicular stimulation with clomiphene citrate and human menopausal gonadotropin

The incidence of pregnancy and abortion was analyzed in 1679 patients having embryos replaced after oocyte recovery and in vitro fertilization in order to alleviate their infertility. In these patients, 364 pregnancies were achieved and 108 abortions occurred. Patients were treated either on their natural cycle, having a spontaneous luteinizing hormone (LH) surge to induce ovulation, or after ovarian stimulation using clomiphene citrate alone or in combination with human menopausal gonadotropin (hMG). The data were assessed in relation to the numbers of embryos replaced, the follicular stimulation and ovulation induction regime used, the dose of gonadotropins and the dose of antiestrogens, and the age of the patient. The most successful treatment for the number of live births per laparoscopy was the use of clomiphene citrate in combination with human menopausal gonadotropin followed by human chorionic gonadotropin (hCG) to induce follicular maturation and ovulation. This treatment produced a significantly higher (P less than 0.001) number of patients with multiple embryos (86.5%). There was no significant effect on pregnancy or abortion with a low (less than 400-mg) or high (greater than or equal to 400-mg) dose of clomiphene. The total dose of gonadotropins used did not influence the incidence of pregnancy or abortion. The use of hCG with hMG induced a significant (P less than 0.01) positive effect on the incidence of pregnancy. The incidence of pregnancy showed a progressive decline with increasing age but there was a highly significant (P less than 0.01) increase in the incidence of abortion with increasing age. With increasing numbers of embryos replaced, up to three, the incidence of deliveries increased.(ABSTRACT TRUNCATED AT 250 WORDS)

Embryo transfer technique as a cause of ectopic pregnancies in in vitro fertilization

Against an overall risk of around 2% ectopic pregnancies in in vitro fertilization programs around the world, we report an incidence more than three times greater (5 tubal ectopic pregnancies in 80 clinical in vitro fertilization pregnancies). Of two techniques used for embryo transfers, one produced a significantly higher risk for ectopic pregnancy (P less than 0.05). Four of the ectopic pregnancies occurred in a small group of 24 patients in whom the embryo transfer technique attempted to deliver the embryos at the uterine fundus (mean distance of catheter insertion 62.9 +/- 7.9 mm from the external cervical os). Only one ectopic pregnancy occurred in 56 patients whose embryos were transferred to a standard, generally midcavity position. It is concluded that the delivery catheter need be inserted only 55 mm as a routine and less in patients with a shortened cervix or with the hypoplastic uterus usually encountered in women with primary ovarian failure who have ovum or embryo donation. In such cases an ultrasonic measurement of length may indicate that a shorter transfer distance is required.

Estradiol in saliva for monitoring follicular stimulation in an in vitro fertilization program

A rapid and sensitive radioimmunoassay (RIA) was developed to compare serum and saliva estradiol (E2) levels in patients undergoing ovulation induction in an in vitro fertilization and embryo transfer (IVF-ET) program. Serum and saliva E2 were compared in 23 patients. The sensitivity of the saliva RIA standard curve was 11 fmol/tube (equal to 3.2 pg/tube). There was a highly significant correlation between serum and saliva E2 throughout the stimulated cycles (r = 0.769; P less than 0.001). The ratio of serum to saliva E2 was constant throughout the stimulated cycles (1.7% +/- 0.3%, mean +/- standard deviation [SD]). The E2 concentration per follicle was 1548 pmol/l in serum and 23 pmol/l in saliva. Mean E2 levels in saliva (+/- SD) were 74 +/- 21 pmol/l at midcycle and 46 +/- 12 pmol/l at midluteal phase. The findings indicate that measurement of saliva E2 provides a reliable, noninvasive method and may replace serum measurements for monitoring stimulated cycles in an IVF-ET program.

Analysis of the outcome of in vitro fertilization in relation to the timing of human chorionic gonadotropin administration by the duration of estradiol rise in stimulated cycles

A retrospective analysis was carried out to assess the outcome of ovarian stimulation on in vitro fertilization when human chorionic gonadotropin (hCG) was administered after 5, 6, or 7 days of continuously rising plasma estradiol (E2). There was no significant difference in the number and size of large follicles in each group although the number of small follicles (less than 15 mm in diameter) decreased significantly after 7 days of E2 rise. After hCG injection in the 7-day group, the E2 level fell below the previous day's value in 40% of patients, whereas a similar fall was observed in only 16% of patients in the 5- and 6-day groups. In those cycles where a luteinizing hormone surge occurred, most surges were detected during the seventh day of E2 rise. The pregnancy rate was 31% when hCG was given after 6 days of rising E2, 21% after 5 days, and 14% after 7 days. In patients achieving pregnancy in the 6-day group, 53% of embryos were derived from leading follicles. In the 7-day group, only 15% of embryos associated with pregnancies were derived from leading follicles. These results strongly suggest that in stimulated cycles, hCG should be administered after 6 days of continuously rising E2. It is therefore postulated that 6 days of rising E2 represents a mean optimal period for follicular growth and oocyte maturation in stimulated cycles.

Human pregnancy by in vitro fertilization (IVF) using sperm aspirated from the epididymis

Spermatozoa were collected by microaspiration from the corpus epididymidis of a 42-year-old man with secondary obstructive azoospermia and used for in vitro fertilization. At insemination 61% of the spermatozoa were motile, with a motility index of 157. One of five eggs was fertilized and this was subsequently transferred to the patient's wife at the two-cell stage. Ultrasound examination and changing hormone levels confirmed an on-going pregnancy, which is currently at 30 weeks of gestation. This technique will provide a useful alternative for the management of some infertile men with obstructive azoospermia.

Comparative analysis of in vitro fertilization methods for establishing successful embryo transfer clinics

A review of the laboratory methods and embryo transfer procedures used by seven of the foremost clinics in the world are discussed and evaluated in this article. Based on these facts an in vitro fertilization clinic was launched in 1983. In the second part of the paper the latest laboratory methods, i.e. ovulation induction plans and the embryo transfer technique of Tygerberg Hospital, are described. One hundred and thirty laparoscopies were performed since 1 May 1984-30 November 1984. Six hundred and one follicles were aspirated, 482 oocytes were obtained, 84% of all oocytes were fertilized, 112 patients reached the transfer stage and 28 pregnancies resulted. A clinical pregnancy rate of 21,4% per transfer and 18,5% per laparoscopy resulted.

Successful pregnancies from the transfer of pronucleate embryos in an outpatient in vitro fertilization program

Twenty-nine infertile women were given clomiphene citrate (100 mg/day, days 3 to 7), human menopausal gonadotropin (150 IU/day, days 7 to 12 or 13), and human chorionic gonadotropin (2000 IU) for the induction of ovulation. Eggs were collected by laparoscopy and preincubated for 6 hours before being cultured with spermatozoa for fertilization. Approximately 16 to 18 hours after insemination, the eggs that showed two pronuclei were transferred to the patient's uterus. As confirmed by the ultrasonic appearance of a gestational sac, six women who received pronucleate embryos became pregnant, and three pregnancies resulted in normal full-term deliveries. These results confirm that, unlike requirements for most laboratory and farm animals, the requirements of synchrony between the preimplantation human uterus and developing embryos are not very stringent. In vitro fertilization treatment procedures can thus be made simpler by the transfer of embryos at the pronucleate stage.

Pregnancy following in vitro fertilization using cryopreserved semen from a man with testicular teratoma

Semen for cryopreservation was collected in a man with a testicular teratoma after unilateral orchidectomy but before chemotherapy which rendered him azoospermic. After two years artificial insemination using this semen in his wife failed repeatedly. The semen quality on thawing was extremely poor in terms of sperm motility. A pre-freeze motility of 90 per cent was reduced to 2 per cent, and the movement was graded as sluggish. Using the techniques of semen and oocyte preparation and in vitro fertilization, a number of cleaving embryos was produced. A pregnancy was established after four of these embryos were replaced in the wife. The pregnancy aborted spontaneously, but a subsequent course of treatment resulted in an on-going twin pregnancy. The potential of in vitro fertilization for overcoming the poor quality of semen after storage by cryopreservation from men with testicular neoplasms is discussed.

Effect of serum source on human fertilization and embryonic growth parameters in vitro

A total of 100 mature oocytes from 13 consecutive patients were randomly assigned from each patient to one of two treatment groups (n = 53 for group 1, n = 47 for group 2). Group 1 oocytes were incubated throughout the culture periods in medium supplemented with 7.5% homologous patient serum. Group 2 oocytes were treated similarly, except the serum supplement was of fetal cord origin. End points for examination included fertilization frequency, normality of fertilization, stage of embryonic development at two time periods, and quality of embryonic development at two time periods. None of the end points examined revealed significant differences between patient serum and fetal cord serum.

Factors affecting human in vitro fertilization: a multifactorial study

The influence of four factors on the cleavage rate of 705 mature oocytes submitted for in vitro fertilization (IVF) was assessed with the use of a multifactorial method, i.e., logistic regression. The studied factors were (1) the regimen for cycle stimulation, (2) cumulus cell mass appearance, (3) semen quality, and (4) the time of incubation of oocytes before insemination. The logistic function permitted testing the respective influence of each factor on the cleavage rate, with the level of the other factors taken into account. The most important factor was the stimulation treatment, the association of human menopausal gonadotropin with clomiphene citrate (CC) giving better results than CC alone. Time of incubation was demonstrated to have no influence on the cleavage rate, whereas semen quality had an influence. A problem was raised by the existence of an interaction between the stimulation treatment used and the appearance of the cumulus cell mass. It can be concluded that adequate cycle treatment and eventually couple selection with respect to the semen quality of the male partner are to be considered in view of obtaining better results in IVF attempts.

Various techniques for oocyte recovery in an in vitro fertilization and embryo transfer program

Oocyte recovery in an in vitro fertilization and embryo transfer (IVF-ET) program can be performed by laparoscopy or by sonography. Most IVF teams use either one or the other of these methods. In Clamart, we undertook 407 IVF attempts from September 1983 to March 1984, 225 by laparoscopy under general anesthesia, 97 by laparoscopy under local anesthesia, and 85 by sonography. Excluding the recovery techniques, all aspects of the program (ovulation monitoring, culture, and transfer) were identical in order to study the effects of the anesthesia and the ultrasound. We did not find any significant difference in pregnancy rates, inclusive of biochemical pregnancies, among these three recovery methods, although ultrasonically guided puncture gave fewer follicles, oocytes, and embryos than laparoscopy.

Results of phase I of the in vitro fertilization and embryo transfer programme at Tygerberg Hospital

Phase I (3 June - 31 October 1983) of the in vitro fertilization (IVF) programme at Tygerberg Hospital is outlined in this article. This programme led to the birth of the first IVF baby in South Africa after fertilization and embryo transfer (ET) took place at this institution. The baby was born on 29 April 1984; a second baby was born on 20 June 1984. During phase I 24 laparoscopies were performed; 32 oocytes were obtained from 56 follicles, of which 62,5% were fertilized. Eleven ETs were performed, which led to 3 pregnancies. An ongoing pregnancy rate of 18% per ET and a pregnancy rate of 12,5% per laparoscopy were achieved.

Culture factors affecting the success rate of in vitro fertilization and embryo transfer

The development of one-cell mouse zygotes to the blastocyst stage in vitro has been used as a quality control for the media and handling procedures employed for human in vitro fertilization and embryo transfer (IVF/ET). One-cell mouse zygotes were placed in culture in medium containing bovine serum albumin. Aliquots of the same batch of medium containing female patients' homologous serum were used for the fertilization and culture of human oocytes. The following procedures were associated with high rates of mouse embryo development and human pregnancies following IVF/ET: adequate gassing and equilibration of the medium, double-rinsing of pipets and catheters used to handle embryos, use of a HEPES-buffered medium for manipulating embryos in the absence of an atmosphere containing 5% CO2, control of excessive temperature in the vicinity of the embryos, and ET using medium containing 50% patient's serum. The institution of these procedures gave more consistent pregnancy rates. However, there was no obvious association between fertilization and cleavage of human oocytes and the quality of the medium ascertained by the mouse embryo development test. In a continuing trial, we are comparing two culture media (modified Tyrode's and a medium formulated on the composition of human fallopian tube fluid [HTF]) and two culture techniques (culture in medium under oil in petri dishes and in loosely capped tubes). Significantly more mouse zygotes developed in HTF medium compared to Tyrode's medium. In a randomized 2 X 2 factorial trial with human IVF/ET, the highest pregnancy rate occurred when fertilization and culture were carried out in HTF medium under oil, but numbers are not yet sufficient to show any statistical difference between treatments.

[Results of diagnostic hysteroscopies in an in vitro fertilization/embryo transfer program]

Twentysix sterile women were examined during the development and growth phase of the follicle, using a microhysteroscope manufactured by Karl Storz, under local anaesthesia. All these patients had been included in the in-vitro fertilisation/embryo transfer (IVF/ET) programme because their oviducts were either missing or had been irreparably damaged. Pathological findings were present in 7 patients. Cervical conditions were normal in 22 patients, and intrauterine conditions were without any abnormal findings in 23 patients. The clinical relevance of the findings with regard to embryo transfer and implantation are discussed. It is concluded that hysteroscopy not only occupies an important rank in the general diagnosis of sterility, but is also of considerable importance in preparatory work for embryo transfer.

A simple technique of ovarian suspension in preparation for in vitro fertilization

Because laparoscopic ovum harvest for IVF is becoming more common, efforts must be made at the time of prior infertility surgery to render the ovaries accessible for ovum recovery. In this report, a simple technique of ovarian suspension in preparation for eventual IVF is described. Seventeen infertile patients undergoing lysis of adhesions underwent ovarian suspension by plication of the suspensory ligament of the ovary with a running suture of 3-0 Prolene, thus apposing the proximal pole of the ovary to the anterior-lateral surface of the uterus. Because the fallopian tube is independent of the sutured structures, the tubal anatomy was undisturbed. Fourteen of these 17 patients have since undergone laparoscopy during IVF. In 12 cases, despite the recurrence of adhesions, the ovaries were accessible for ovum recovery from all aspects. Two patients conceived normally after the lysis of adhesions. This simplified ovarian suspension represents an effective technique for facilitating ovum recovery for IVF which may not disturb fallopian tube ovum pickup or transport mechanisms.

The development of a programme for in vitro fertilisation in New Zealand

The first seven months experience of a programme for in vitro fertilisation at National Women's Hospital in Auckland is described. Following a five month period of technique development, 36 women with tubal infertility were admitted to the programme from July 1983 to February 1984. A clinical pregnancy rate of 15% (6/41 laparoscopies) was achieved during this period.

Comparative study of ultrasonically guided percutaneous aspiration with local anesthesia and laparoscopic aspiration of follicles in an in vitro fertilization program

Twenty patients from our in vitro fertilization program were randomly divided into two groups. Ten women underwent follicular aspiration during laparoscopy while they were under general anesthesia and 10 women had an ultrasonically guided follicular aspiration with local anesthesia. All patients had mechanical infertility, and ovulation was induced with human menopausal gonadotropins. In both groups the same aspiration system with a needle of 1.4 mm inner diameter and a continuous suction at 120 mm Hg were used. In the laparoscopy group the oocyte recovery rate was 82.5% and the fertilization rate 62.5%, with one twin pregnancy; in the ultrasound group the oocyte recovery rate was 75%, and the fertilization rate 61.9%, with a singleton pregnancy. Implications of these results are discussed.

Simplification of the method of in vitro fertilization: sonographic measurements of follicular diameter as the sole index of follicular maturity

As a simplification of the in vitro fertilization (IVF) procedure, repeated sonographic scanning of follicular diameters in stimulated cycles was performed, until the largest visible follicle reached a mean diameter of at least 20 mm, at which time human chorionic gonadotropin (hCG) was administered. Follicle puncture was performed either guided by sonography or by laparoscopy 34-36 hr after the hCG injection, and following insemination oocytes were cultured for 48-60 hr before embryo transfer (ET). Serum levels of luteinizing hormone (LH), prolactin (PRL), and estradiol-17 beta (E2) at the time of hCG injection as well as follicular fluid levels of follicle stimulating hormone (FSH), LH, and PRL as well as progesterone (P), testosterone (T), and E2 at the time of puncture were determined in retrospect using specific radioimmunoassay (RIA). It was found that the knowledge of a single value of LH or E2 in serum should have been of little additional value for the decision to give hCG in all stimulation models used: clomiphene + hCG, human menopausal gonadotropin (hMG) + hCG, and clomiphene + hMG + hCG. The concentrations of the three steroids measured in follicular fluid were, in a high proportion of the follicles, within a normal range in all stimulation models. The group receiving clomiphene + hMG + hCG appeared promising through its higher proportion of estrogenic follicles. It is concluded that sonographic measurement of follicular diameters may be used as the sole index of follicular maturity in an IVF program.(ABSTRACT TRUNCATED AT 250 WORDS)

[Micromanipulatory sperm injection--a new method in the treatment of infertile males]

Three couples were selected for this preliminary sperm injection study with their consent, since in all three cases the zona free hamster egg penetration test was negative and in one couple previous attempts of in vitro fertilization were unsuccessful. Of 22 eggs, recovered from three patients, 9 from each patient 3 were injected with sperm, while the others were inseminated by the standard IVF-protocol. Before manipulating human eggs extended experiments were performed with animals eggs, so decreasing the rate of damage to under 10%. Additionally we optimized the method by using an individual adapted equipment. Manipulation was performed by penetration of the zona pellucida with a 5 to 7 mu thick injection pipet into the perivitilline space so damaging of the egg cytoplasm was avoided. This special technique for sperm injection was not used till now in this indication. From the nine eggs used in this experiment one egg developed a pronucleus and one egg developed to a four-cell stage. We could not achieve a pregnancy.

[Methodological study for human in-vitro fertilization related to maturity of gametes]

The correlations with maturity of gametes and fertilizability was studied. Specimens of semen were treated by several methods for induction of capacitation and acrosome reaction (AR). Follicular oocytes were recovered with endoscopic aspiration procedures, and divided to two groups: 1, maturing in vivo (preovulatory) and 2, immature. Immature oocytes were divided further into two subgroups: 1, germinal vesicle breakdown (GVBD) and 2, first polar body formation (FPB), after maturation culture. The sperms treated with the centrifuge-trypsinization-layering method showed a higher incidence of in-vitro fertilization (69.2%) and cleavage (51.3%) of human preovulatory eggs compared with other capacitation inducing methods. It was found that human spermatozoa that have undergone the acrosome reaction prior to zona attachment are capable of fertilizing eggs under the in vitro conditions. On the estimation of fertilizability with reference to egg maturity, 52.5% (21/40) of IMIV-GVBD and 64.7% (22/34) of IMIV-FPB eggs were fertilized. However, only 12.5% (5/40) of IMIV-GVBD and 11.8% (4/34) of IMIV-FPB eggs cleaved. These results showed that IMIV eggs had fair fertilizability, but no developmental capacity after the first cleavage. This may due to prematurity of the cytoplasm in IMIV eggs.

[Pregnancy after fertilization in vitro and embryo transfer]

The first 13 pregnancies established by in vitro fertilization and embryo transfer. A tubal factor was the main indication for in vitro fertilization (IVF) in 10 patients, whereas in three couples infertility was caused by the infertile sperm. The mean age and duration of infertility in female patients were 33.5 and 11.4 years, respectively. Multiple follicular growth was stimulated by either clomiphene citrate (100-150 mg during 5 days), clomiphene citrate + HMG + HCG, or HMG + HCG. Timing of ovulation was determined by assaying serum estradiol, progesterone and LH levels. The ultrasound monitoring of follicular growth was determined on a daily basis. Endogenous LH surge was observed in one patient, whereas in others 5000-10,000 IU HCG were needed to induce ovulation. All oocytes were recovered by laparoscopy. There were 3.8 oocytes per patient on an average. Fifty-six percent of oocytes were preovulatory. All oocytes were allowed to mature in vitro for 3 to 7 hours (mean 5.7 hours). The fertilization and cleavage rates were 76% and 72% respectively. Only one polyspermic fertilization was observed. Forty-five hours after the insemination the embryos between the 2-cell and 6-cell stages were reimplanted into the uterus. Using various ET cannulas, one to seven embryos per patient (2.7 embryos on the average) were replaced into the uterine cavity, 5 mm below the fundus. Only four embryo replacements were completely atraumatic. No medications were used for the luteal phase support. The corpus luteum function and early pregnancy were controlled by serial measurements of serum progesterone, estradiol and beta HCG. Three clinical miscarriages and full-term deliveries were recorded.(ABSTRACT TRUNCATED AT 250 WORDS)

[Laparoscopic aspiration of oocytes for in vitro fertilization and embryo transfer]

Within the in vitro fertilization and embryo transfer procedure, 127 laparoscopies were performed in 89 women. The only indication was tubal infertility. There were 116 gonadotropin stimulated cycles and 11 clomiphene citrate stimulated cycles. Because of a limited ovarian access laparoscopic adhesiolysis was necessary in 30%. Egg recovery amounted to 440 oocytes in 92% successful laparoscopies, which represents 4.1 oocytes per laparoscopy. This resulted in 15 pregnancies of which 3 ended with spontaneous abortion, 6 biochemical and 6 ongoing pregnancies. Two pregnancies resulted in the live birth of normal twins, and one in the birth of a healthy girl.

Three years of in vitro fertilization at Norfolk

During the 3 years from 1981 to 1983, 319 consecutive patients in 560 cycles were treated in a program of in vitro fertilization at Norfolk. All patients were stimulated by human menopausal gonadotropin supplemented by human chorionic gonadotropin. There were transfers in 429 cycles, resulting in 105 pregnancies. Over the 3-year span, the pregnancy rate by cycle was 19%; by transfer, 25%; and by patient, 33%.

The use of ovulation-inducing agents in in-vitro fertilization

In view of the increasing pregnancy rate associated with increased numbers of embryos transferred to the uterus, it is optimal to transfer more than one embryo to each patient. This requires treatment with ovulation-inducing agents to increase the number of preovulatory follicles developing. However, the degree of ovarian "hyperstimulation" must be limited to prevent subsequent luteal-phase dysfunction. In all probability, the ideal regimen for enhanced follicular recruitment to achieve these goals has not as yet been determined. Up to this time multiple different regimens have been used throughout the world, all of which have achieved an increase in the number of embryos available for uterine replacement. Unfortunately, as the degree of augmented follicular development is increased, there appears to be a progressive shortening of the luteal length. It remains to be determined whether or not this shortening of the luteal length can be overcome by pharmacologic support of the luteal phase. In addition, if all embryos recovered are to be transferred to the uterus in the treatment cycle, there is a substantial risk (ranging from 10% to 35%) that if a woman becomes pregnant, she will have a multiple pregnancy. As ethical constraints challenge the advisability of selecting only some of the available embryos for uterine replacement, the development of cryopreservation for subsequent uterine replacement appears highly desirable.

Successful in vitro fertilization and embryo transfer in cynomolgus monkeys

We have started an in vitro fertilization program in cynomolgus monkeys in an effort to develop an appropriate animal model to improve our knowledge of early embryonic development. In 16 of 25 animals treated with menopausal gonadotropins, preovulatory follicles developed. Follicular aspiration was performed at laparotomy after human chorionic gonadotropin injection. A total of 299 follicles were aspirated, and 251 oocytes were recovered. Oocytes were cultured in 1 ml of growth medium or 100 microliter droplets of medium under mineral oil. Semen samples were obtained by electroejaculation, and the oocytes were inseminated 4 to 24 hours after aspiration. Culture under mineral oil significantly increased the fertilization and cleavage rates. Of 68 embryos produced, 24 have been used in 10 embryo transfers, resulting in two pregnancies.