Cryopreservation of human embryos obtained after gamete intra-Fallopian transfer and/or in-vitro fertilization

During a one-year period 636 excess embryos obtained after in-vitrofertilization and gamete intra-Fallopian transfer combined within-vitro fertilization were cryopreserved using two differentprotocols. For early stage embryos including the pronucleatestage, 1,2-propanediol was used as cryoprotectant (procedureA, adapted from Renard) and for later stage embryos dimethylsulphoxidewas used in protocol B, adapted from Trounson and Mohr. Afterthawing 288 embryos, half of them were of sufficient qualityto be replaced. After cryopreservation, procedure A gave thebest survival in embryos having 2 blastomeres; for later stageembryos best survival was obtained using the dimethylsulphoxideprotocol. Survival after cryopreservation was also clearly relatedto the quality of the embryos prior to freezing. Embryos werereplaced during endocrinologically monitored natural cyclesand were transferred in synchrony between endornetrial and embryonicage. After replacement of 126 embryos in 110 patients, 20 pregnanciesoccurred. So far six healthy children have been born, two patientsaborted and 12 pregnancies are ongoing. In this series no statisticaldifference was observed between the implantation rate of embryoscryopreserved by procedure A or B. Six pregnancies occurredin patients from the oocyte and embryo donation programme. Anadequate cryopreservation programme circumvents the difficultproblem of synchronizing the ovarian cycles of donor and acceptorpatients.     

Immunoreactive renin variations during fertile and infertile hyperstimulated cycles with in-vitro fertilization and embryo transfer or gamete intra-Fallopian transfer

The concentrations of prorenin (PR) and active renin (AR) weredetermined sequentially during ovarian hyperstimulated cyclesfor in-vitro fertilization -embryo transfer or gamete intra-Fallopiantransfer. AR and PR increased during the early luteal phaseand PR was highly correlated with the progesterone concentration.In fertile cycles, AR increased more rapidly after HCG injectionand AR and PR levels were significantly higher during the lateluteal phase. These results confirm the role of the renin angiotensinsystem in ovarian physiology.     

Fertilization in vitro of supernumerary oocytes following gamete intra-Fallopian transfer (GIFT)

Gamete intra-Fallopian transfer (GIFT) was performed in 130treatment cycles over a 17-month period. In 91% (118/130) ofthe cycles one or more oocytes were available for inseminationin vitro and only GIFT cycles with supernumerary oocytes wereincluded in the present study. Pituitary and ovarian suppressionwas arhieved with buserelin followed by stimulation of multifolliculardevelopment by human menopausal gonadotrophin (HMG). Failureof supernumerary oocytes to fertilize was associated with asignificantly reduced pregnancy rate (3/23; 13%) compared tocycles where fertilization occurred in vitro (35/95; 37%). Thesefindings demonstrate that the outcome of IVF of supernumeraryoocytes may be of particular diagnostic value in couples wherethe female partner has not conceived following treatment byGIFT after pituitary down-regulation with buserelin and ovarianstimulation with HMG.     

Eighty consecutive cases of gamete intra-Fallopian transfer

Eighty patients with the main problems of unexplained infertility,oligospermia and endometriosis were treated with gamete intraFallopiantransfer (GUT). From 80 treatment cycles, 29 women conceived(36.3%). Of these, four were biochemical pregnancies and thereforethe clinical pregnancy rate (25/80) was 31.2%. There were sixsets of multiple pregnancies, a multiple pregnancy rate of 24%.Three women (12%) miscarried. The pregnancy rates in the patientswith unexplained infertility, oligospermia and endometriosiswere 33.3, 16.7 and 38.5%, respectively. The transfer of fouroocytes appears to increase the pregnancy rate without increasingthe risk of multiple pregnancy. The presence of in-vitro fertilizationof excess oocytes after GIFT did not correlate with the finaloutcome of GIFT     

Preterm delivery, low birthweight and small-for-gestational-age in liveborn singleton babies resulting from in-vitro fertilization.

The Medical Research Council In-Vitro Fertilization (IVF) Register report on births resulting from assisted conception in Great Britain demonstrated a high incidence of preterm and low birthweight babies. This incidence remained high even when the analysis was restricted to singleton babies. The present paper investigates possible risk factors for prematurity, low birthweight and small-for-gestational-age (SGA) in singleton IVF births. Thirteen per cent of singleton IVF babies were preterm, 11% low birthweight and 17% small-for-gestational-age. Analysis by multiple regression indicated that hypertension during pregnancy was an independent risk for preterm delivery, low birthweight and SGA, bleeding during pregnancy for preterm delivery, and the number of embryos transferred and the type of infertility for low birthweight.     

The role of early post-implantation beta-HCG levels in the outcome of pregnancies following in-vitro fertilization

Daily plasma beta-HCG levels from days 11 to 18 after ovum retrieval(OR) were evaluated in a group of 73 women who became pregnantfollowing in-vitro fertilization and embryo replacement (IVF-ER).The 47 patients who had a normal ongoing pregnancy could bedistinguished from the 26 patients with a pathological pregnancy(pre-clinical abortion, clinical abortion and tubal pregnancy)by the mean daily beta-HCG levels, their mean daily increaseand the intercept and slope of the beta-HCG regression analysis.The mean daily beta-HCG levels of the normal pregnancies weresignificantly higher than: (i) pre-clinical abortions on days12–18 after OR; (ii) clinical abortions on days 12–16;and (iii) tubal pregnancies on days 12–17. Using quadraticdiscriminant analysis, normal and pathological pregnancies couldalso be distinguished by their absolute beta-HCG levels on day13 after OR with 27.6 mIU/ml being the cut-off point. Our resultsindicate that the outcome of pregnancy following IVF-ER couldbe predicted with a high degree of probability by monitoringdaily beta-HCG levels within the first 2 weeks following OR.     

Pregnancy: Transvaginal crown--rump length measurements of 224 successful pregnancies which resulted from gamete intra-Fallopian transfer or in-vitro fertilization

The crown—rump lengths (CRL) of 224 pregnacies which resultedfrom gamete intra-Fallopian transfer (GIFT) or in-vitro fertilization(IVF) were assessed two to four times in the first trimester.The results were compared with some of the published articleswhich assessed CRL in spontaneous and induced pregnancies. Therange of CRL measurements from this study was generally smallerthan the previously published data, although all women wenton to deliver normal fetuses at full term weighing > 2.5kg. It was not possible to identify a clear reason for thisfinding, but factors which might have been relevant includedpopulation differences, more accurate estimation of ovulation/conceptiontime, the exclusive use of vaginal ultrasonography in this studyand variations in the embryonic implantation/development times.There is a need to review the commonly used CRL charts in viewof the increasing use of transvaginal ultrasonography and theincreasing number of pregnancies with known ovulation/conceptiontimes. Each centre should aim to establish the normal CRL rangefor its own population.     

A prospective controlled study of in-vitro fertilization, gamete intra-fallopian transfer and intrauterine insemination combined with superovulation.

The relative effectiveness of in-vitro fertilization (IVF), gamete intra-Fallopian transfer (GIFT) and intrauterine insemination (IUI) combined with superovulation in the treatment of infertility were compared in 151 couples undergoing a single cycle of treatment. Treatment was selected as appropriate (IVF for tubal disease, GIFT or IUI/superovulation for nontubal infertility) but possible bias due to non-randomization was overcome by all couples having had favourable fertilization in a previous cycle of IVF. Furthermore, in a preliminary study of initial IVF treatment in 265 couples from whom the study patients were drawn, implantation and pregnancy rates in the diagnostic groups were similar. In the definitive study comparing IVF, GIFT and IUI/superovulation, the pregnancy rate observed with GIFT was highest (40%) but this was not significantly higher than with IVF (28%) or IUI/superovulation (20%). However, the implantation rate per egg transferred by GIFT (21%) was significantly higher than the implantation rate per embryo transferred by IVF (11%). Although the pregnancy rates with GIFT were not statistically greater than with IVF, a significant advantage is likely to be observed in larger groups in view of the better implantation rate. The lower pregnancy rates with IUI superovulation are to be expected because of limited ovarian stimulation, they are nevertheless of comparative interest.     

Comparison of concurrent pregnancy rates for in-vitro fertilization-embryo transfer, pronuclear stage embryo transfer and gamete intra-Fallopian transfer

Concurrent pregnancy and implantation (sacs/embryos transferred)rates were compared for 84, 77 and 49 cases of in-vitro fertilization–embryotransfer (TVF–ET), pronuclear stage embryo transfer (PROST)and gamete intra-Fallopian transfer (GIFT), respectively. Allcases reported occurred during an 18-month interval since theinitiation of PROST by our programme. Leuprolide acetate wasused with follicle stimulating hormone and human menopausalgonadotrophin for follicular stimulation of all but donor oocytecases (n = 9). Clinical pregnancy (per transfer) and implantationrates were significantly higher (P < 0.03) for PROST (52.4%,20.2%) in comparison with IVF–ET (26.9%, 11.4%). Ratesfor GIFT (48.9%, 18.4%) were not significantly higher (P = 0.10,0.14) than for IVF—ET. This was probably due to the lowernumber of GIFT than PROST procedures performed. The total pregnancyrate for GIFT (biochemical, ectopk and clinical combined) wassignificantly greater (P < 0.05) than for IVF—ET. Pregnancyand implantation rates for PROST and GIFT were similar. Theseresults support the use of PROST rather than IVF—ET forall cases in which the woman has one functional Fallopian tube.Furthermore, to maintain equivalent rates of pregnancy withPROST and GIFT, it is suggested that GIFT should not be usedfor cases of male-factor infertility without first documentingnormal rates of in-vitro fertilization with PROST.     

The leuprolide flare regime for in-vitro fertilization/gamete intra-fallopian transfer and embryo cryopreservation.

Gonadotrophin releasing hormone agonists (GnRHa) are now well established as adjuvant agents for in-vitro fertilization (IVF)/gamete intra-Fallopian transfer (GIFT) but several different modes of usage have been proposed. Our experience with 328 cycles of leuprolide used in a flare regime is reviewed. An endocrinologically proven flare effect was associated with a reduction of human menopausal gonadotrophin (HMG) usage (10 versus 16 ampoules) and a lower cycle cancellation/conversion rate (7.4 versus 11.3%). Overall, satisfactory rates of oocyte recovery (93%, mean number of oocytes 7.0), clinical pregnancy (24.4% per oocyte recovery) and pregnancy from frozen/thawed embryo transfers (14%) were achieved. The flare protocol appears to be a satisfactory choice for the majority of subjects but careful monitoring is required to avoid the potential for ovarian hyperstimulation.     

The contribution of embryo cryopreservation to in-vitro fertilization/gamete intra-Fallopian transfer: 8 years experience

In this paper, the authors summarized their experience withembryo cryopreservation over an 8-year period. The results,therefore, reflect the long-term benefit of embryo cryo-preservationto the overall in-vitro fertilization/gamete intra-Fallopiantransfer (IVF/GIFT) programme and to the women who had embryoscryopreserved. The stable survival rate of thawed embryos andpregnancy rate, especially over the past 4 years, suggests thatthe results can reliably be used to evaluate the efficacy ofthe embryo cryopreservation programme. The ongoing pregnancyrate of frozen/thawed embryo transfer is 10.9%, comparable withthe ongoing pregnancy rate of fresh IVF/embryo transfer in ourunit over the same period. In addition to those factors knownto affect the pregnancy rate in fresh IVF/GIFT cycles, suchas age of the recipients and number of embryos transferred,the major factor affecting the efficacy of the cryopreservationprogramme is the number of oocytes retrieved in the initialstimulation cycle, and the number of embryos available for cryopreservation.The storage time of cryopreserved embryos will also have a significanteffect on the realization of the total potential of embryo cryopreservation.Overall the contribution of cryopreservation to our IVF/GIFTprogramme is substantial, increasing pregnancy rate by 4%, whilethe greater net benefit, of course, is for the women who hadembryos cryopreserved (pregnancy rate increased by 7%), especiallyfor those who returned for frozen/thawed embryo transfer cycles(pregnancy rate increased by 11%).     

In-vitro fertilization, gamete- or zygote intra-fallopian transfer for the treatment of male infertility

This retrospective study compares in-vitro fertilization and embryo transfer (IVF-ET), gamete intra-Fallopian (GIFT) and zygote intra-Fallopian transfer (ZIFT) for the treatment of male infertility in 266 couples (n = 318 cycles). The IVF-ET technique revealed a total pregnancy rate of 14.1% per cycle and 29.1% per transfer. The conception rate with GIFT was 17.8%; an abortion rate of 50% was noted. The ZIFT procedure scored a 20.9% total pregnancy rate per cycle and 33.3% per transfer. The cumulative take home baby rates per couple for IVF-ET, GIFT and ZIFT were 13.5, 7.0 and 20.0%, respectively.     

Effect of aspirating needle calibre on outcome of in-vitro fertilization

Thirty patients with intact ovaries undergoing ultrasound-guidedtransvaginal oocyte retrieval for in-vitro fertilization treatmenthad their ovaries randomized for follicular aspiration withsmall and large aspiration needles while under mild sedation.Collections using smaller diameter needles had no significanteffect upon the number of oocytes collected per follicle aspirated,or on the subsequent fertilizing capacity of those oocytes.There was significant reduction in pain perceived by the patientwhen the smaller needle was used during the collection.     

Improved methods for preparation of culture media for in-vitro fertilization and gamete intra-Fallopian transfer

A new method for preparation of culture media for IVF-ET andGIFT was developed which eliminated the requirement for volumetricsand glassware. Water weight was used instead of volumetricsfor preparation of media. Media prepared by the volumetric andwater weight methods were compared for (i) preparation time,(ii) pH, (iu) osmolarity and (iv) the percentage of two-cellmurine embryos developing to blastocysts. The time requiredfor preparation of media was significantly less for the waterweight method. Following equilibration with 5% CO², no differenceswere observed between the two methods for pH, osmolarity ordevelopment of embryos to the blastocyst stage. Time for mediapreparation and osmolarity was less variable among preparationdays for the water weight method. These results suggest thatmedia can be prepared more efficiently and precisely with thewater weight method than with the standard volumetric methodused by most IVF laboratories. The former method eliminatesconsiderable technician time which must be devoted to propercleaning/sterilization of volumetrics and the possibility ofmedia contamination by residual substances remaining on volumetricsfollowing improper cleaning.     

Luteal function associated with single, multiple and ectopic embryo implantation in natural cycles or after ovarian hyperstimulation for in-vitro fertilization/gamete intra-fallopian transfer

Levels of reproductive steroids and gonadotrophins were analysed retrospectively during the peri-implantation period following non-conceptional and conceptional natural cycles and in cycles associated with ovarian hyperstimulation for in-vitro fertilization or gamete intra-Fallopian transfer. In cycles not associated with conception, the luteal phase of hyperstimulated cycles (n = 100) was characterized by higher serum progesterone and oestradiol levels (P less than 0.01) and with an earlier decline in steroids than in natural cycles (n = 21). On day 11 (day of oocyte recovery = day 0), the level of progesterone in twin (n = 59) and triplet (n = 13) pregnancies was higher than singleton pregnancies (n = 176) (P less than 0.006, P less than 0.006 respectively) while those destined to abort (n = 66) had lower progesterone levels (P less than 0.01). Ectopic implantation (n = 11) had the lowest progesterone concentrations on day 11 (P less than 0.01) and this may imply a delay in corpus luteum rescue or a later implantation time than intrauterine conception.     

Serum inhibin levels in gonadotrophin stimulated in-vitro fertilization/gamete intra-fallopian transfer cycles.

Serum inhibin concentrations of 64 cycles of in-vitro fertilization--embryo transfer (IVF-ET) or gamete intra-Fallopian transfer (GIFT) have been analysed retrospectively. No significant difference was observed in serum inhibin levels of cycles stimulated with buserelin and human menopausal gonadotrophin (HMG) or HMG alone. During the late follicular phase, serum inhibin was higher in cycles resulting in pregnancy than in cycles without a pregnancy (peak values on day +1: 8.3 versus 6.4 IU/ml, respectively). The same difference was found between stimulation cycles resulting in a viable or a non-viable pregnancy (peak values on day +1: 8.3 versus 7.5 IU/ml). However, these differences were not significant. During the early luteal phase, serum inhibin values were similar in these groups of patients. Our results indicate that the use of the gonadotrophin-releasing hormone (GnRH) analogue buserelin, in combination with HMG, for ovarian stimulation does not affect inhibin production by granulosa cells in vivo. The late follicular and early luteal concentrations of serum inhibin have to be considered unsuitable as predictors in IVF/GIFT cycles with respect to pregnancy and pregnancy outcome.     

Obstetric outcome of twin pregnancies after in-vitro fertilization: a matched control study in four Dutch university hospitals

In singleton pregnancies after in-vitro fertilization (IVF), increased rates of obstetric and perinatal complications have been reported. Studies that compared IVF twin pregnancies with spontaneously conceived twins have yielded conflicting results. We compared 96 IVF twin pregnancies to 96 controls after elaborate matching. The design of our study precluded matching by zygosity. The monozygosity rate was higher in the control group and this implies that beforehand the risk for a less favourable outcome in the control group was higher than in the IVF group. However, the average birthweight of the IVF children was less than that of children in the control group (P = 0.04). This was not due to more intrauterine growth retardation in the IVF group. The mean gestational age at birth was 5 days shorter in IVF than control pregnancies, and although this difference was not significant it might explain the lower birthweight in the IVF group. The discordance rate in the IVF group was significantly increased. We found no difference in perinatal mortality and morbidity. We conclude that this study provides further evidence for a different outcome of IVF twin pregnancies in comparison with spontaneously conceived twin pregnancies.     

Analysis of ectopic pregnancies resulting from in-vitro fertilization and embryo transfer

The purpose of this study was to analyse the risk factors, stimulation characteristics, site and outcome of pregnancy and future fecundity of patients who develop ectopic pregnancies after in-vitro fertilization (IVF). Of 3145 transfer cycles between January 1981 and July 1989, 27 (3.3%) of the resulting 825 pregnancies were ectopic. There was a significantly greater incidence of a prior ectopic pregnancy in the study group compared to the controls. Compared to matched controls with intrauterine pregnancies, the study group had significantly higher peak oestradiol levels. Twenty-one ectopic pregnancies were ampullary, two were interstitial, one was abdominal, one was cervical and two were heterotopic. Sixteen of the patients subsequently underwent 40 IVF attempts with a pregnancy rate of 28% per transfer. We conclude that patients with a prior ectopic pregnancy are at risk for an IVF ectopic pregnancy. The subsequent IVF outcome of those who develop ectopic pregnancies after IVF is encouraging.     

Obstetric and perinatal outcome of pregnancies following intracytoplasmic sperm mjection

The aim of this study was to describe the obstetric and perinataloutcome for births following intracytoplasmic sperm injection(ICSI). Of 210 infants born, 140 were singletons and 70 weretwins. There were no triplets or higher births. The multiplebirth frequency was 20%. Overall, 17% of deliveries were preterm,although for singleton pregnancies the incidence was reducedto 9%. The median birth weight of all live born infants was3168 g and of singletons 3470 g. Of all infants, 17% had a lowbirth weight (<2500 g) and 2% had a very low birth weight(<1500 g). Two major malformations occurred in two singletonchildren and four minor malformations occurred in four children.This was within the range of expected values in Sweden. Karyotypingwas performed in 58 pregnancies. All of them were normal. Theperinatal mortality was 0.5%. In conclusion, in this observationalstudy from Sweden of the first infants born after ICSI in ourprogramme, the incidence of multiple births, preterm births,low birth weight babies and congenital malformations was lowcompared with other series of in-vitro fertilization pregnanciesnot associated with ICSI.     

Simultaneous intrauterine and ectopic pregnancies following in-vitro fertilization and gamete intra-fallopian transfer. A review of nine cases

This paper reports nine cases of simultaneous intrauterine and ectopic pregnancies which followed in-vitro fertilization (three cases) and gamete intra-Fallopian transfer (six cases). The ectopic pregnancies were treated by aspiration and injection of potassium chloride and methotrexate (five cases), salpingectomy (three cases) or laparoscopic evacuation (one case). In five of the nine patients the intrauterine pregnancies continued until after the 35th week and the patients delivered live infants. The role of vaginal ultrasound scanning in making the diagnosis was emphasized. The literature on heterotropic pregnancy is reviewed.