In Vitro Fertilization: The First Three Decades pdf

In Vitro Fertilization: The FirstThree Decades Jean Cohen International Federation of Fertility Societies, European Society of Human Reproduction and Embryology, Paris, France Howard W..

In Vitro Fertilization: The First

Three Decades

Jean Cohen

International Federation of Fertility Societies, European Society of

Human Reproduction and Embryology, Paris, France

Howard W Jones, Jr

Eastern Virginia Medical School, Norfolk, Virginia and Johns Hopkins

University Hospital, Baltimore, Maryland, U.S.A

The birth of the world’s first baby born as a result of in vitro fertilization (IVF) in July 1978 was by no means a chance event Indeed, in the long evolu-tion of reproducevolu-tion, concepevolu-tion by IVF represents the end of a continuum which originated with childbirth wholly dependent on chance but which today is almost exclusively under human control Today, nearly all forms

of infertility can be treated by the various techniques of assisted repro-duction, which are now responsible for the birth of around two million children worldwide

THE HISTORY OF THE PAST

Although the origins of our medical knowledge of human reproduction are usually attributed to Hippocrates, so often described as the ‘‘father of medi-cine,’’ we do know that in the fifth century B.C. it was believed that both males and females each produced two seminal liquors, one stronger than the other; a blend predominantly with the former would produce a male offspring, with the latter a female In the following century, Aristotle

1

proposed that the first stage of a human being was indeed the egg found in females Sperm had the power to give that egg its shape; the male would bring immaterial strength, the female material substance For centuries, people lived with this concept of pre-formation, even after De Graaf described the follicle in 1672 and, at the same time, Leuwenhoek the sperma-tozoa Only in 1875 would Hertwig demonstrate in the sea urchin that only one sperm cell would penetrate the egg to achieve fertilization

In 1786, Hunter performed the first artificial insemination in humans, and in 1866 Sims the first donor insemination In 1833, the cytologist Van Beneden demonstrated that gametes had only two chromosomes

in the ascaria The two chromosomes of the male nucleus would join with the two chromosomes of the female to form the nucleus of a new zygote, thereby laying the foundations for the discovery of the hereditary principle

In 1903, a Danish pharmacist, Johannsen, coined the term ‘‘gene,’’ from which Bateson 3 years later defined the new science of ‘‘genetics.’’ Almost

50 years later, in 1953, Watson, Crick, and Wilkins discovered the double helic structure of DNA and in 1956 Tijo and Levan identified 46 chromo-somes in the human

Equally important were the advances made by gynecologists in their understanding of the physiology of reproduction By observing the effects

of ovariectomy, they were able to explain the function of the ovary and in particular the menstrual cycle; the first treatments were developed as a result

of injecting extracts of ovarian tissue The concept of ‘‘hormone’’ activity was proposed by Baylin in 1904, and the subsequent discovery of the differ-ent hormones persisted throughout the rest of the 20th cdiffer-entury

1950–1978

Studies of animal and then human fertilization began in the second half

of the 20th century In 1954, Thibault achieved the first fertilization in vitro

in the mammal (in the rabbit); the following year, Chang (1,2) succeeded in growing rabbit embryos derived from oocytes fertilized in vitro, and in 1959 achieved a live birth by transfer of an in-vitro-fertilized oocyte In 1965, Edwards (3) determined that human oocytes removed from ovarian biopsies required 37 hr to complete their maturation in vitro

This time was also the beginning of the gynecologist’s interest in infer-tility It was in 1959 that the first Congress on Infertility was held in New York Five years earlier, in 1954, the first human pregnancy derived from frozen sperm was achieved, and the following year Pincus (4), who

at the time was best known for his (unsuccessful) attempts to fertilize human oocytes in vitro, published the first results on hormonal contraception (for Enovid1, Searle Pharmaceuticals) In 1958 and 1960, Gemzell and Lunen-feld obtained the first pregnancies following treatment with human pituitary gonadotrophin (hPG) and human menopausal gonadotrophin (hMG),

respectively (5,6) In 1961, Klein and Palmer (7) described the first aspir-ation of a human oocyte during laparoscopy

However, throughout this time there was also a man working to achieve in humans what had seemed possible from work in animal models, much of it his own work in mice: IVF and embryo transfer Eventually, in his scientific rigor and disciplined success, this man would change the face of human reproduction, demonstrating throughout persistence, self-denial, and exceptional confidence This man was Edwards

Edwards had completed his Ph.D in 1958 on developmental genetics

in mice His studies, using diakinesis and metaphase-2 as markers, had shown that mice needed around 12 hr to achieve oocyte maturation, but now, as his work progressed from mouse models to the human, it was clear that human eggs required much longer However, at the same time he and colleagues in Glasgow had produced the world’s first embryonic stem cells from rabbit embryos Intrigued by the therapeutic potential of these stem cells, Edwards turned to the maturation and fertilization of human oocytes

in vitro—as a source of stem cells and for other research purposes And it was from this work with human embryos—during an intense 6-wk period

at Johns Hopkins Hospital in Baltimore—that Edwards found that human oocytes required 37 hr to reach full maturity, and thus 35–40 hr after ovu-lation before insemination could be carried out By 1969, working with Ph.D student Barry Bavister, Edwards was able to fertilize human eggs without any obvious need for sperm capacitation

It was at this time—in 1967—that one of us (Cohen) first met Edwards Both (Cohen and Edwards) were attending a conference on immunology in reproduction in Bulgaria We met again in 1972 at an IFFS Congress in Tokyo, and here we talked of the possibilities of IVF in humans At least,

I listened, as he explained his vision of the future of human repro-duction—IVF, cryopreservation, preimplantation, and genetic diagnosis

I asked myself if he was serious, but I quickly understood that his was the vision of a true prophet

Edwards had tried unsuccessfully to collaborate with clinicians in Cambridge and London to supply him with human oocytes Frustrated

in these efforts, he thus turned to the United States and in 1965 had joined Georgeanna and Howard Jones at Johns Hopkins where ovarian tissue (from wedge biopsies) was more readily available And it was here, during this 6-wk working visit, that he obtained human oocytes, confirmed the pre-cise timing of human oocyte maturation Back in the United Kingdom, his clinical collaborations continued to prove fruitless, until his chance meeting

at a London conference with the gynecologist Steptoe At the time Steptoe was working in the small northern town of Oldham and already had much experience in the surgical use of laparoscopy Steptoe immediately agreed to collaborate with Edwards, and so began—in 1968—the partnership that would leave such a lasting legacy in reproductive medicine

The story of Edwards and Steptoe is well known, but for them it was also a difficult one—the long drives of Edwards from Cambridge to Oldham (180 miles each way), the laparoscopic recovery of oocytes from the ovary, the start of embryo transfers in 1971, ovarian stimulation with hMG, clomi-phene, luteal support, and constant failure—until the first ectopic pregnancy

in 1975 Finally, despite accusations of malpractice by some U.K colleagues and after 32 embryo transfers, their first healthy pregnancy was achieved with the birth of Louise Brown on July 25, 1978 (8)

I was surprised that the announcement of the world’s first IVF birth was received in such a variety of ways Certainly, there were very few people

in the world who immediately understood the huge importance of its scien-tific achievement Many doubted it, or did not even pay it much attention

I remember that I made the trip to London in early 1979 to hear Edwards and Steptoe report their medical and scientific success to the Royal College

of Obstetricians and Gynaecologists, and I remember, too, the discussions and doubts when I arrived However, after their precise and somewhat unsettling lecture (both the biologist and the clinician presenting data), any doubts in the audience evaporated and the meeting ended to the tune

of ‘‘For he’s a jolly good fellow ’’

Immediately after the birth of Brown, the attention of Edwards and Steptoe turned to extending their clinical work, but their progress was halted

by the retirement of Steptoe from Britain’s nationalized health service It took two more years before an alternative private service could be set up

at Bourn Hall near Cambridge, which in time would become one of the most progressive and best known in the world

However, while Edwards and Steptoe planned their move to Bourn Hall, other groups throughout the world were inspired by the U.K success and set about their own efforts to repeat it Like Edwards and Steptoe, they were contemplating a treatment for tubal infertility, with the idea that IVF would circumvent the tubal blockage if tubal surgery had failed

1978–1982

The embryo that became Brown was derived from a natural—and not stimulated—cycle Thus, with the success of Edwards and Steptoe showing the way, the predominant scenario of these first IVF attempts was the natural cycle, determination of the luteinizing hormone (LH) peak and follicle punc-ture during laparoscopy There was also a new demand for the development

of culture media

In Australia at the time there was already a long history in repro-ductive medicine By 1970, Prof Wood had established a combined research team in Melbourne involving the Royal Women’s Hospital and the University of Monash Johnston was the Medical Director at the former, while Leeton and Talbot comprised the medical staff at the latter, with

Lopata and Trounson handling the biology This joint group was working with hormonally stimulated IVF cycles throughout the mid-1970s, using hPG or clomiphene and hMG However, following the birth of Brown, the Melbourne group also turned its attention to the natural cycle Improvements in culture media were initiated by Trounson, while the devel-opment of Teflon-lined catheters by Buttery and Kerin improved the technique of embryo transfer Australia achieved its first IVF birth— the third in the world—in June 1980 when Candice Reed was born at the Royal Women’s Hospital

In June 1978, Howard and Georgeanna Jones had retired from Johns Hopkins—where Edwards had joined them for his 6-wk working visit in 1965—and had been asked by Andrews to set up a division of reproductive medicine at the Eastern Virginia Medical School in Norfolk They began their IVF program in 1980, but, following 41 laparoscopies to collect oocytes, they had achieved embryo cleavage in only 13 patients, and no pregnancies following transfer

In 1981, Georgeanna Jones proposed a change to hMG and the stimu-lated cycle to obtain more oocytes, a move which yet again prompted intense debate on the relative merits of the natural or stimulated cycle in IVF The Norfolk group had its first success in the 13th attempt in a stimulated cycle, the first American IVF baby born in December 1981

In France, two groups were making progress in friendly compe-tition At the university hospital in Clamart, Frydman as clinician and Testart as biologist were focusing their research on the LH peak, and in

1981 developed an assay for the initial rise of LH in plasma (LHSIR) (9) This assay would allow the accurate prediction of the start of the LH surge, and thus more time for the organization of follicle puncture

In Sevres, a non-university hospital, the biologists Mandelbaum and Plachot and I found ourselves frustrated by the absence of a laboratory

on site, and adopted a policy of transporting oocytes by thermos flask to the INSERM laboratory of the Hospital Necker, 30 minutes away by taxi

It was also at Sevres that Pez and I began tracking follicular growth by ultrasound

Both French groups benefited from the help of veterinary researchers

at INRA (Institut National de la Recherche Agronomique), one of whom, Menezo, had developed the B2 culture medium known as the ‘‘French medium.’’

France’s first IVF babies were born at Clamart in February 1982 and

at Sevres the following June And there were now several other live births being reported from groups elsewhere—in Sweden, Finland, the Netherlands, and Germany, as well as in the United Kingdom, United States, and Australia In Vienna, Feichtinger and Kemeter began with clo-miphene cycles in the summer of 1981 and, doing their own biology, had their first live births (twins) in August 1982

One catalyst for the surge of activity in IVF at this time was a meeting at Bourn Hall in September 1981 organized by Edwards for those groups world-wide now actively involved and reporting results—from Bourn Hall itself, Basel, Gothenburg, Kiel, Manchester, Melbourne, Norfolk, Paris, and Vienna It was here that many of us met for the first time, and the atmosphere was warm and friendly Comparing experiences was reassuring for everyone, and one important conclusion did emerge—a preference for stimulated cycles, which would generate more oocytes and allow a better prediction of the tim-ing of ovulation Now, looktim-ing back through the proceedtim-ings of that 1981 meeting and the reported discussions, I can see the following:

1 ovarian stimulation was mainly with clomiphene,

2 ultrasound was already in use (with Feichtinger) for monitoring follicular growth,

3 a concern for the effect of gas on oocyte quality during laparoscopy,

4 a concern about quality control in culture media and during lab-oratory processes,

5 and the conviction of Edwards that his former use of Primolut1 (norethisterone) during the luteal phase of his earlier stimulated cycles would explain the failure of his first attempts at IVF; most participants at the meeting seemed to agree that, if post-aspiration progesterone values were low, a progesterone supplement would

be needed during the luteal phase Primolut, Edwards concluded, was probably an abortifacient

If my descriptions of this first clinical phase of IVF seems to focus on just a few groups, it is because there was so little reporting of scientific data from elsewhere and because only the announcement of a pregnancy allowed some form of recognition from the scientific and lay communities A fuller review of these pioneering days of IVF can be found in a series of articles in Human Reproduction Update by, Trounson, Dawson, Jones, Hagekamp, Nygren, Hamberger, and myself (10)

This was also, let us not forget, a period of general doubt in the scien-tific integrity of IVF and in its wider clinical application In 1982, there were only 11 reported IVF births in the world, but this does not mean that the

‘‘celebrity’’ groups were the only ones doing IVF successfully In many cit-ies, there were young groups making their first attempts, and many of them traveled to the United Kingdom, United States, and Australia for their training In the years which followed, they too would achieve their first preg-nancies and live births

1982–1992

The next decade was a time of huge progress in IVF There was an explosion

in the number of centers performing IVF in many countries, and it was also

at this time that the first discussions on the ethics of assisted reproduction began in earnest, many of which would pave the way for subsequent legislation and guidelines

Each year saw important new clinical and scientific developments Among the milestones were

1982: The recognition of poor and high responders to hMG, the first ultrasound-guided aspiration of follicles, and the first reports of GnRH agonist use for the downregulation of pituitary hor-mones in IVF (11–13)

1983: Human embryo freezing (14)

1984: The first pregnancy following gamete intrafallopian transfer (GIFT) (15)

1986: The first pregnancy following zygote intrafallopian transfer (ZIFT) (16)

1986: The first human pregnancy following oocyte freezing (17) 1988: The first report of a human pregnancy following sub-zonal insemination (18)

1989: Vitrification of human oocytes (19)

1990: The first live birth following preimplantation genetic diagnosis, the detection of aneuploidy following polar body testing, and the first description of assisted hatching (20–22)

1991: The first clinical use of GnRH antagonists for the suppression of pituitary hormones (23)

1992: Intracytoplasmic sperm injection (ICSI) (24)

ICSI would become the most successful technique introduced in the decade, thereafter applied throughout the world to overcome fertilization failure as a result of male factor or unexplained infertility The success of ICSI would also be shown to be independent of the three basic sperm parameters, motility, morphology, and concentration

Throughout the decade, there was a huge increase in the use of assisted reproduction and in its success In 1986, approximately 2000 babies were born following IVF, with half of them conceived at Bourn Hall However,

by 1989, the first year of data presented in the initial world collaborative report at the Seventh World Congress of IVF in Paris in 1991, that total had increased to more than 18,000 (Table 1)

In January 1984, Seppala had sent a questionnaire to 65 individuals

or groups then working in IVF which had produced data on 10,028 cycles Success rates according to the type of ovarian stimulation is shown in Table 2, and according to the number of embryos transferred in Table 3

In 1988, I reported a similar collaborative study at the Sixth World Congress of IVF in Melbourne which showed that, of 2342 pregnancies

in the database, 24.8% were spontaneously lost and 5.2% were ectopic (Tables 4 and 5)

Table 2 Type of Ovarian Stimulation and Number of Pregnancies Achieved

Stimulation

No of reporting teams

No of pregnancies/

No of cycles

Success (%) per cycle None; natural cycle 7 41/352 11.6 Clomiphene/hCG 44 256/3083 8.3 Clomiphene/hMG/hCG 50 377/3847 9.8 Clomiphenea 14 167/980 17.0 Clomiphene/hMGa 7 53/340 15.6

a Spontaneous LH surge.

Abbreviations: hMG, human menopausal gonadotropin; hCG, human chorionic gonadotropin Source: From Ref 36.

Table 1 In Vitro Fertilization: 1989 General Data

FR USA UK

Aus/

NZ DE Scand BE JP CA ES Clinics

reported

115 180 24 40 33 14 124 14 Clinics

participating

50 161 35 23 37 25 14 67 10 10 Studied

cycles

15,880 18,211 10,489 9345 8385 6245 4578 3726 3180 OPU

cycles

15,725 15,392 8514 7356 5759 5379 3750 3438 2724 1247 Transfer

cycles

10,531

(þ999)

13,523 6553 6261 4365 4581

(þ100)

3040 2571 (þ93)

2233 1158 Clinical

pregnancies

2526

(þ142)

2811 1354 1040 900 997

(þ21)

741 421 (þ5)

391 244 Deliveries 1893a 2146 982 755 646 705a 306a 264 194 Babies

including

stillborn

2531a 2929 964 926a 391 286 232

Total

babies

reported

since start

11,127 11,015 4595 3275 1864 2428 552 1337

Abnormal

babies

181 27 18 22

a

Including frozen-thawed transfers (numbers in parentheses).

FR; France, USA; United States of America, UK; United Kingdom, AU; Australia,

KR; Korea, CZ; Czechoslovakia, GR; Greece, Yug; Yugoslavia, NL; Netherlands,

Abbreviation: IVF, in vitro fertilization.

Source: From Ref 35.

KR CZ GR Yug NL SG CN BR IN PT EG TR IE Total %OPU

5 5 8 7 1 6 7 3 9 3 4 1 1
649

3 5 6 2 1 6 4 3 4 2 1 1 1 469

1456 1456 1232 769 696 617 504 383 271 243 66 >87,732

1240 1234 1000 857 656 618 509 455 322 222 168 66 34 76,030 100 1019

(þ41)

524 835

(þ21)

655 531 (þ49)

483 (þ60)

358 383 267

(þ18)

178 139 65 29 60,282 79.3 191

(þ2)

51 156

(þ1)

89 140 (þ7)

110 (þ11)

94 85 51 51 27 8 2 12,480 16.4

137a 32 100 61 112a 95a 68 33a 40 20 6 0 >8595 12.0

122a 34 98 72 162a 137a 90 50a 62 31 8 >9125

151 55 206 153 399 139 202 171 109 117 105 13 >38,013

3 0 4 1 15 0 2 2 3 0 0 >278 1.5

New Zealand, DE; Germany, Scand; Scandinavia, BE; Belgium, JP; Japan, CA; Canada, ES; Spain, SG; Singapore, CN; China, BR; Brazil, IN; India, PT; Portugal, EG; Egypt, TR; Turkey, IE; Ireland.

It seems worthwhile to pause here and reflect on our main concerns during this decade of such great progress in reproductive medicine First, our main scientific efforts were concentrated on fertility itself, whether to prevent pregnancy with contraception or to facilitate it with assisted repro-duction In IVF, we were looking for ways to increase the number of oocytes available for fertilization but to decrease the number of sperm cells neces-sary to achieve it (as it was by now quite clear that the failure of fertilization was often the result of a low concentration of motile sperms) At the same time, we were also searching for ways—as reflected in the techniques of zona drilling or partial zona dissection, or indeed in GIFT or ZIFT—to bring gametes closer together in time and space, and break through the physio-logical barriers of the oocyte

However, the indications for IVF were not yet changing in any major way—and would not until the introduction of ICSI opened a door to the treatment of male infertility From the beginning, IVF had remained indi-cated mainly for the treatment of tubal infertility as a result of blocked or damaged Fallopian tubes Thus, there was a lively debate in the early

NZ;

1980s following developments in microsurgery on how tubal blockage might best be treated; the microsurgeons were insistent that their new surgical techniques were potentially more effective than IVF However, IVF quickly won that debate by gradually extending its indications far beyond the range

of surgery, first into tubal infertility with patent but diseased tubes, and then into polycystic ovary disease and other idiopathic conditions By the time the indications had been stretched to male infertility following the introduc-tion of ICSI in the early 1990s, the debate between assisted reproducintroduc-tion and surgery was long over Today, ICSI accounts for around 40% of all the indications for assisted reproductive technology (ART)

Table 3 Clinical Pregnancies Relative to Number of

Embryos Replaced

No of embryos

replaced

No of pregnancies/

No of replacement cycles

Success rate (%) One embryo 317/3321 9.5

Two embryos 366/2514 14.6

Three embryos 259/1340 19.3

Four or more

embryos

197/818 24.1

Source: From Ref 36.

Table 4 Features of the Population Under Study: 2342 Pregnancies in Women of Mean Age of 33 Yr

(%)

Indications for IVF

Type of ovarian stimulation

Oocyte collection

Idiopathic 11.0

Male infertility 3.5

Abbreviations: IVF, in vitro fertilization; hMG, human menopausal gonadotropin; FSH, follicle stimulating hormone.

Source: From Ref 37.