Pre-embryo Transfer Research Articles

Freeze-all embryo transfer awareness and acceptance of IVF-ET patients in China.

The aim of the study was to determine the level of awareness and acceptance of in vitro fertilization pre-embryo transfer (IVF-ET) patients for freeze-all embryo transfer, improve relevant technical specifications, and optimize treatment results based on medical experience.Questionnaires were completed by women who received in vitro fertilization embryo transfer. A total of 377 valid samples were included into this study. Through focus group discussions and tablet assisted intercept interviews, we analyzed the basic situation, the awareness for frozen-all embryo transfer, and the need for frozen-all embryo transfer information for infertile patients.In this study, 60% of patients received IVF-ET for the first time, whereas the remaining patients received IVF-ET more than once. We investigated the current awareness and acceptance of IVF-ET patients for freeze-all embryo transfer quantificationally. Patients were grouped based on quantitative measurements, and the mainstream group of patients (72.7%) was precisely the patients who were worried and concerned of frozen-all embryo transfers. Although few of them could “rationally accept the comparative advantage of the technology,” this group was vulnerable to doctors’ guidance and education. Eventually, this group of patients accepted the frozen-all embryo transfer.Since there are no certain criteria for the kind of embryo transfer patients and reproductive centers should take, the choice should be taken individually according to the social economic situation and acceptance of patients for the frozen embryo transfer, as well as the technology of the reproductive center.

Association between serum HBV-DNA with sperm parameters and out-comes of in vitro fertilization preembryo transfer

HBV可以通过血睾屏障进入睾丸组织和精液中,可能影响精液质量,降低男性生育能力[1].近年来,接受辅助生殖技术(ART)治疗的夫妻中HBV感染及高HBV-DNA载量者并不少见,男方慢性HBV感染且血清HBV-DNA拷贝＞5.0×102 IU/ml的患者接受ART治疗后是否对体外受精-胚胎移植(IVF-ET)结局有影响还不清楚.本研究对男性HBV-DNA阳性(其配偶完全排除HBV感染的可能)和阴性对照行IVF-ET治疗的夫妻进行比较,旨在探讨男方HBV-DNA高拷贝数对IVF-ET治疗结局可能的影响. 关键词：乙型肝炎病毒;精液参数;体外受精-胚胎移植

Effects of Liuwei Dihuang Granule (六味地黄颗粒) on the outcomes of in vitro fertilization pre-embryo transfer in infertility women with Kidney-yin deficiency syndrome and the proteome expressions in the follicular fluid

To observe the effects of Liuwei Dihuang Granule ([symbols; see text], LDG) for tonifying Kidney (Shen) on the outcomes of in vitro fertilization pre-embryo transfer (IVF-ET) of infertility women with Kidney-yin deficiency syndrome and to explore its mechanism by detecting the proteome expression in the follicular fluid. Sixty-six infertility patients of Kidney-yin deficiency syndrome who would undergo IVF-ET, were randomly assigned to a treatment group and a control group according to a random number table, 33 cases in each group. Another 33 cases of non-Kidney-yin deficiency syndrome was taken as a syndrome-control group. Besides Western routine therapy, LDG was given 3 menstrual cycles before IVF to the treatment group, and a placebo granule to the control and syndrome-control groups. The scores of Kidney-yin deficiency symptoms (sore waist and knees, dry vagina, dysphoria with feverish sensation in the chest, palms and soles, etc.) were assessed, the number of retrieved oocytes, rates of high quality oocytes and embryos, fertility rate and clinical pregnancy rate were recorded, and the follicular fluid was collected on the day when the ovum was picked up, the differential protein expression was detected using two-dimensional gel electrophoresis, and then, matrix assisted laser desorption ionization time-of flight mass spectrometry (MALDI-TOF-MS) was applied to identify the proteins. The syndrome score in the treatment group decreased significantly from 16.09±2.58 to 8.67±2.13, while it changed insignificantly in the control group, with a significant difference in the lowering score between the two groups (P<0.05); the high quality rates of oocytes and embryos and clinical pregnancy rate were all superior in the treatment group to the control group (82.29% vs 78.08%, 76.76% vs 68.79%, 63.64% vs 36.36%, all P<0.05). The protein expression map from the follicular fluid showed that compared with the control group, 33 differential protein expressions were found in the syndrome-control group, among which 18 were down-regulated, and 15 up-regulated; in the treatment group 28 differential protein expressions were found, among which 15 were down-regulated, and 13 up-regulated. Through MALDI-TOF-MS, 14 proteins were identified (P<0.05). For the infertility patients undergoing IVF, LDG could alleviate clinical symptoms, improve rates of high quality oocytes and embryos, so as to raise clinical pregnancy rate. The mechanism may be through regulating proteome expression in the follicular fluid to improve the developmental microenvironment for oocytes which would lead to a successful embryo implantation.

Relationship between oxidative stress and clinical pregnancy in assisted reproductive technology treatment cycles

PurposeTo examine the relationship between serum total oxidant (TOS) and antioxidant (TAS) levels and clinical pregnancy in assisted reproductive technology (ART) cycles.MethodsPrior to and after oocyte pick-up (OPU) and embryo transfer (ET), blood samples were collected from gynecologically normal females (n = 70) who were enrolled for ART solely due to male factor infertility. TAS, TOS levels and oxidative stress indexes (OSI: TOS/TAS) in four phases of treatment cycle (pre and post OPU and ET) between clinically pregnant and non-pregnant patients were compared. Critical cut-off values of significantly different TAS, TOS levels and OSIes for clinical pregnancy were established.ResultsThe TAS levels in patients with clinical pregnancy were significantly higher in all of the four phases of the cycle. Post-OPU and pre-ET TOS levels were significantly higher in clinically pregnant patients. According to OSIes; only the pre-OPU OSI was significantly lower in clinically pregnant patients compared with non-pregnant ones. Moreover, the highest area under the ROC curve (AUC) from the seven different significant measurements [1) pre-OPU OSI, 2) pre-OPU TAS, 3) post-OPU TAS, 4) pre-ET TAS, 5) post-ET TAS, 6) post-OPU TOS, 7) pre-ET TOS] was related to pre-OPU OSI.ConclusionsIn ART cycles, women with a higher total antioxidant status prior to and after OPU and prior to and after ET have an increased probability of clinical pregnancy. Additionally; OSI before OPU was one of the most important determinants for clinical pregnancy, so the oxidant and antioxidant balance is as important as the antioxidant concentration alone.

Investogation of anxiety state for IVF-ET patients during caesarean perioperative period

Objective To study the anxiety state of IVF-ET （ in vitro fertilization pre-embryo transfer） patients during caesarean perioperative period, in order to take positive measures to improve nursing quality. Methods 40 eases of IVF-ET pregnant women who had caesarean from January 2011 to February 2012 were chosen as the observational group, while 40 cases of conventional pregnant women who had caesarean during the same period due to funnel shaped pelvis, less amniotic fluid and so on were chosen as the control group. State- Trait Anxiety Inventory was used to conduct psychological evaluation 1 hour and a day before the surgery, as well as 3 days after the surgery. Results The scores of S-AI scale 1 day, 1 hour before and 3 days after the surgery were respectively （43.05 ± 5.715 ）, （45.10 ± 5. 728 ） and （38.95 ± 5. 387 ） in the observational group, and （41.18 ±3. 686）, （42.20 ± 2. 875） and（38. 10 ± 3. 311 ） in the control group, and the differences were statistically significant （t =0.031,2. 862,0.85, respectively; P 〈0.05）. Conclusions The state of anxiety of IVF-ET patients before the surgery is more severe than that of conventional patients, but better after the surgery. Psychological support and help should be provided for IVF-ET patients during caesarean perioperative period to reduce their anxiety. Key words: IVF-ET; Anxious state ; Cesarean section ; Maternity; Perioperative period

Retrospective analysis of treatment for severe ovary hyperstimulation syndrome complicated by pleural effusion and ascites

To investigate the effectiveness of treatment for severe ovary hyperstimulation syndrome (OHSS) complicated by pleural effusion and ascites after in vitro fertilization preembryo transfer (IVF-ET). One hundred and thirty-two patients with severe OHSS in our hospital (from January 2007 to December 2010) were retrospectively analyzed and the efficacy of three therapeutic methods was compared. Twenty-five patients in group I were treated with low-molecular dextran and albumin, 67 patients in group II were treated with 6% medium molecular-weight hydroxyethyl starch, and 40 patients in group III were treated with active aspiration of pleural effusion and ascites. All three therapies improved the symptoms of OHSS and various blood biochemical parameters. The duration of hospitalization of group III [(7.4±4.5) d] was significantly less than those of group I [(21.4±9.2) d] or II [(15.6±6.7) d], and the cost of group III [(2656.2±1882.8) Yuan] was also significantly lower than that of group I or II [(11937.6±7989.8) and (5182.7±2991.7) Yuan, respectively]. Abdominal B ultrasonography-guided trans-abdominal wall aspiration of pleural effusion and ascites combined with blood volume maintenance is an effective and economical way to treat OHSS.

Transient β2-Adrenoceptor Activation Confers Pregnancy Loss by Disrupting Embryo Spacing at Implantation

Pregnancy loss is a serious social and medical issue, with one important cause associated with aberrant embryo implantation during early pregnancy. However, whether and how the process of embryo implantation is affected by environmental factors such as stress-induced sympathetic activation remained elusive. Here we report an unexpected, transient effect of β2-adrenoreceptor (β2-AR) activation (day 4 postcoitus) in disrupting embryo spacing at implantation, leading to substantially increased midterm pregnancy loss. The abnormal embryo spacing could be prevented by pretreatment of β2-AR antagonist or genetic ablation of β-AR. Similar β2-AR activation at day 5 postcoitus, when implantation sites have been established, did not affect embryo spacing or pregnancy outcome, indicating that the adverse effect of β2-AR activation is limited to the preimplantation period before embryo attachment. In vitro and in vivo studies demonstrated that the transient β2-AR activation abolished normal preimplantation uterine contractility without adversely affecting blastocyst quality. The contractility inhibition is mediated by activation of the cAMP-PKA pathway and accompanied by specific down-regulation of lpa3, a gene previously found to be critical for uterine contraction and embryo spacing. These results indicated that normal uterine contraction-mediated correct intrauterine embryo distribution is crucial for successful ongoing pregnancy. Abnormal β2-AR activation at early pregnancy provided a molecular clue in explaining how maternal stress at early stages could adversely affect the pregnancy outcome.

Estados emocionais de casais submetidos à fertilização in vitro

A infertilidade interrompe um projeto de vida pessoal e do casal, produzindo sofrimento psíquico. O desenvolvimento das técnicas de reprodução assistida possibilitou a solução para casais que anteriormente não teriam alternativas de tratamento. Assim, a fertilização in vitro constitui uma nova fonte de esperança para ter um filho, mas, ao mesmo tempo, pode ser acompanhada de muitas dificuldades. O objetivo deste estudo foi comparar os estados emocionais de homens e mulheres submetidos à fertilização in vitro e verificar a relação entre estado emocional das mulheres e ocorrência de gravidez. Foram avaliados vinte casais submetidos ao primeiro ciclo de fertilização in vitro, entre o 5º e o 10º dia após a transferência dos pré-embriões. A avaliação foi realizada por meio de testes psicológicos e entrevistas. As mulheres apresentaram níveis mais altos de ansiedade e depressão que os homens. A autoestima delas mostrou-se mais baixa. Um quarto das mulheres que apresentaram sintomas psicoemocionais não engravidou, porém esta relação não foi significativa. Concluiu-se que as mulheres apresentaram mais ansiedade e sintomas depressivos que os homens e autoestima mais baixa. O grupo de mulheres com sintomas psicoemocionais apresentou tendência a não engravidar.

History of spontaneous abortion increases the risk of oocyte donation pregnancy loss

A history of live birth may be an advantage to women who later need to undergo fertility treatments, although supporting data is lacking. We sought to see if pregnancy history, including live birth and frequency of spontaneous abortion (SAB) would relate to the incidence of pregnancy and miscarriage in women undergoing oocyte donation. Retrospective chart review of 606 donor oocyte transfers from January 2001– December 2004. All recipients were screened and treated for correctable anatomic causes of infertility prior to enrolling in donor egg (DE). Pre-embryo transfer data collected included the number of full term deliveries, pre-term deliveries, SAB, elective terminations and ectopic pregnancies. Post DE transfer data included delivery, no successful implantation, SAB, elective termination and ectopic pregnancy. Each cycle was assigned to three main groups; GxPx (x ≥ 1), GxP0 and G0P0. GxP0 was subdivided into those with history of (1) elective abortion only and (2) SAB and elective abortion or SAB only. Data was analyzed using chi square. 606 recipient cycles resulted in 369 pregnancies, 322 live births and 40 SAB. There was a significant difference between SAB rates in those with a history of successful pregnancy vs. those with history of SAB only (2.78% vs. 8.14% P<0.05). There was also a significant difference in the DE live birth rate of patients with previous history of live birth compared to those with history of spontaneous abortion only (61.81% vs. 44.19% P<0.01). There was no significant difference in the pregnancy or live birth rate in the GxPx group compared to the G0P0 group. Patients with history of elective abortion only had a pregnancy rate of 65.51% and a DE live birth rate of 54.10%, comparable to G0P0 group. Table 1Pregnancy outcomes after donor oocyte transferGestational HistoryGxPx N = 144GxP0 N = 172G0P0 N = 229Pregnancy rate (%)61.81 (89/144)44.19 (76/172)54.15 (124/229)Live birth rate (%)64.58 (93/144)54.10 (93/172)62.45 (143/229)Spontaneous abortion rate (%)2.78 (4/144)8.14 (14/172)6.55 (15/229) Open table in a new tab Women with a previous history of SAB have an increased risk of miscarriage and decreased live birth rate when compared to women who have had a live birth and who have never been pregnant. This model confirms that some women with anatomically normal uteri have intrinsic factors, uterine or systemic, that increase their risk for miscarriage. Oocyte donation provides an excellent model to study the etiology of pregnancy loss.

Early Embryo Cleavage and Mononucleate Blastomeres as Predictors of Embryo Implantation Potential

To evaluate the predictive value of early embryo cleavage (25 - 27 hours post insemination/ICSI) of day two 4-cell preembryos which showed a single nucleus in each blastomere (“4-cell / 4 nuclei” preembryo) at the time of transfer. In previous studies, we have demonstrated that transfer of day two 4-cell preembryos with a synchronous appearance of nucleation yields a significantly higher implantation rate compared to transfer of 4-cell preembryos with an asynchronous appearance of nucleation (0 - 3 blastomeres showing a single nucleus). Also early embryo cleavage has been claimed to be an important marker for implantation potential of an embryo. Retrospective study. Single embryo transfers. Early cleaving preembryos, which were “4-cell / 4 nuclei” preembryos at the time of transfer, were primarily chosen for transfer. If no such embryo was available, a “4-cell / 4 nuclei” preembryo which had not cleaved early was taken for transfer. 364 consecutive fresh day two single embryo transfers of “4-cell / 4 nuclei” preembryos were performed from February 2004 to February 2005. Implantation rates (at least a gestational sac at ultrasound examination at 7 weeks of gestation) of “4-cell / 4 nuclei” preembryos which had or had not cleaved early were analysed. The pregnancy/implantation rates after transfer of day two “4-cell / 4 nuclei” preembryos with or without early cleavage are shown in the table. Tabled 1 The observation early embryo cleavage adds no extra in predicting implantation potential of a day two 4-cell preembryo with mononucleate blastomeres.

Nuclear status of four-cell preembryos predicts implantation potential in in vitro fertilization treatment cycles

To assess the value of routine screening of nuclear status of day-2 four-cell preembryos for single embryo transfer (SET) in predicting implantation. Retrospective analysis. Private IVF unit. A total of 1,985 fresh embryo transfers on day 2 or day 3 were performed from January 2002 to November 2004. In 1,295 (65.2%) of these transfers, SET was performed. All day-2 four-cell preembryos transferred in SET cycles (n = 861) were analyzed retrospectively for outcome in terms of implantation rate and its relation to the number of visible mononucleate blastomeres (MNBs), the degree of fragmentation, and equality of blastomeres. Light microscopic evaluation of preembryos before transfer on day 2. Implantation rate. The number of MNBs was found to be related to implantation, whereas blastomere equality and rate of embryo fragmentation were not. The implantation rate was statistically significantly higher in cycles where a four-cell preembryo with four MNBs was transferred than after transfer of a four-cell preembryo with zero to three MNBs (42% versus 22%). In a logistic regression analysis, nucleation of all blastomeres was the only morphologic parameter that was associated with the implantation rate. Evaluation of nuclear status of four-cell preembryos is important in predicting implantation potential. Visualization of four MNBs in a four-cell preembryo predicted a statistically significant higher implantation rate than in cases where not all four blastomeres were mononucleate.

Day 5 vs. day 6: A Comparison between fresh and frozen blastocysts transfer cycles

Blastocyst transfer (BL-ET), as opposed to day 3 preembryo transfers, represents a beneficial treatment for IVF patients because it allows for optimal embryo selection, which in turn results in high pregnancy (PR) and implantation (IM) rates with a concomitant reduction in the incidence of multiple gestations (only one to two blastocysts transferred). One of the main questions is if there is a significant difference in developmental potential of day 5 (D5) blastocysts as compared to day 6 (D6). Further, if such a difference exists, is it also reflected when comparing D5 and D6 frozen/thawed cycles? To answer these questions and determine which day, if either, is most advantageous for preembryo transfer (ET), we compared D5 and D6 PR and IM outcomes in fresh and frozen BL-ET cycles.

The value of day 3 preembryo selection as a predictor for preembryo transfer and cryopreservation on day 5 or day 6

While an IVF cycle is considered successful when a pregnancy is achieved, it is optimal to reduce the risk of multiple gestations. To prevent this risk, the ASRM guidelines suggest reducing the number of preembryos (PE) transferred back to the patient, particularly on day 3. The decision regarding which preembryos should be selected for embryo transfer (ET) can be difficult, as the preembryos chosen for transfer on day 3 are generally selected based upon their morphological appearance. The choice of blastocyst for day 5 or day 6 ET is much easier since they have undergone their own self-selection during the additional days of culture.

Pre-embryo transfer sham at the time of embryo transfer improves clinical pregnancy rates

Objective: Over the past several years clinical pregnancy rates with ART have improved. While many variables have been analyzed to determine their effect on ART outcomes, the role of embryo transfer (ET) techniques is unquestionably important. Immediate pre-embryo transfer sham has been utilized in cases thought to be difficult transfers, however the effect of a routine pre-transfer sham is unproven.

Too many twins, triplets, quadruplets, and so on: a call for new priorities.

Assisted reproductive technology has enabled thousands of infertile couples to experience the joys of parenthood. At various times, however, significant problems have come to light concerning the providing of infertility treatment in the United States. An early problem was misleading advertising by some infertility programs, particularly in regard to pregnancy success rates. This unacceptable activity suggested the need for more oversight of assisted reproductive technology and prompted the passage of a federal law requiring the reporting of success rates in a standardized format. Another problem, one that was especially disturbing, was the transfer of preembryos to infertile women at the University of California, Irvine, without the consent of the progenitor couples. Disclosure of these events added fuel to the debate over whether assisted reproductive technology should be subject to greater governmental regulation.

Progesterone affects the cervix prior to embryo transfer.

Objective: With advancing technology, the day of in vitro fertilization (IVF) embryo transfer has progressed from day 2 to day 3 to day 5 post-fertilization. Exogenous progesterone administration is initiated at the time of oocyte retrieval to help prepare the endometrium for embryo implantation. Hence, prolonging the time of embryo transfer from day 2 to 5 correlates with an increasing duration of progesterone exposure to the female reproductive tract. As progesterone may affect the cervix and subsequently influence the success of pre-embryo transfer, this research evaluated the effects of increased duration of progesterone exposure on cervical anatomy and physiology.

Does the choice of catheter for preembryo transfer influence pregnancy rate?

Objective: Appropriate delivery of preembryos to the uterine cavity is crucial to successful in-vitro fertilization (IVF). Although the type of catheter used for transfer may impact pregnancy rate, the choice is generally program-dependent and based on the previous experience of the operator. This study compares cycle outcomes using Wallace and Tomcat catheters, and examines whether assisted hatching (AHA) is associated with negative findings in either group.

Minimal precycle testing and ongoing cycle monitoring for in vitro fertilization and fresh pre-embryo transfer do not compromise fertilization, implantation, or ongoing pregnancy rates

Objective: We sought to assess the fertilization, implantation, and ongoing pregnancy rates with a minimal precycle and ongoing cycle monitoring protocol for in vitro fertilization and embryo transfer. Study Design: Retrospective review was conducted of 103 consecutive cycles of fresh in vitro fertilization and embryo transfer from 1996 to 1998. Precycle screening included semen analysis without strict morphologic analysis, and hysterosalpingography-sonohysterography within the last year. Serum prolactin, serum thyroid-stimulating hormone, reactive plasma reagin, human immunodeficiency virus, rubella titer, blood type, hepatitis B surface antigen, and hepatitis C antibody testing was performed on all patients within 3 months of cycle initiation. Women ≥37 years old underwent clomiphene challenge testing. The monitoring protocol included the following: baseline transvaginal ultrasonography after 12 to 14 days of midluteal gonadotropin-releasing hormone agonist down-regulation to assess endometrial thickness and adnexal appearance, transvaginal ultrasonography for follicle evaluation at 7 and 10 days, serum estradiol assay if ≥20 follicles, quantitative β-human chorionic gonadotropin 12 to 14 days after pre-embryo transfer, repeat quantitative β-human chorionic gonadotropin 3 to 5 days later, and transvaginal ultrasonography for intrauterine gestational sac confirmation 7 to 9 days after the initial positive pregnancy test result. The dose of gonadotropin used remained constant unless the sonogram obtained on day 7 indicated a suboptimal response (<3 follicles each, with an average diameter of 10 to 12 mm) or hyperresponse (≥15 follicles with an average diameter of 10 to 12 mm). Results: The per embryo implantation rate (fetal cardiac activity) was 13.1%, and the live birth rate per 100 pre-embryo transfers was 31.5 for patients ≤40 years old. The average number of pre-embryos transferred was 3.1. The singleton pregnancy rate was 71%, and there were no multiple gestations greater than twins. The mean number of oocytes fertilized was 66%. There was 1 case of failed fertilization with intracytoplasmic sperm injection. There were two other cases of failed fertilization. One case of severe ovarian hyperstimulation occurred in spite of cryopreservation of all embryos. Conclusions: In vitro fertilization and embryo transfer can be accomplished with minimal precycle testing and ongoing cycle monitoring without compromising fertilization, implantation, and ongoing pregnancy rates. This results in reduced overall costs for couples. (Am J Obstet Gynecol 2000;182:1623-8.)

Obstetric outcome of pregnancies following ICSI, classified according to sperm origin and quality.

The aim of this study was to report the outcome of all clinical pregnancies obtained after intracytoplasmic sperm injection (ICSI) performed during a 5 year period at two fertility clinics, with special reference to delivery outcome associated with different sperm origin and quality and the transfer of fresh or frozen-thawed pre-embryos. A total of 1293 clinical pregnancies was analysed. Deliveries occurred in 75.9% (n = 982) and early spontaneous abortion, late spontaneous abortion and ectopic pregnancy in 21.4, 1.0 and 1.2% respectively. Multiple birth occurred in 21.3% (208 sets of twins and one set of triplets) of the deliveries, with the highest incidence in the epididymal sperm group (30.2%) and lowest in the cryopreserved group (13.7%). A total of 1192 infants was born. Preterm birth occurred in 15.7% of all deliveries. Preterm birth was not related to sperm origin or quality but was related to multiple birth. The prematurity rate was 8.4%, 42.3% and 100% for singletons, twins and triplets respectively. Singleton infants born after cryopreservation as embryos had a significantly higher birthweight than the ejaculated sperm group with fresh embryo transfer. The perinatal mortality rate was 11.7 per 1000 born infants. Eighty-seven of the 1192 infants (7.3%) had a malformation, 40 of which were minor. The perinatal mortality rate and the malformation rate were similar in the different subgroups. Prenatal karyotyping was performed on 149 fetuses (12.5%) and abnormal results were found in four cases (2.7%). In conclusion, obstetric outcome of ICSI pregnancies was similar to that of conventional IVF and was not influenced by sperm origin or quality. The high incidence of multiple births is still the major concern.

Transfer of cryopreserved-thawed pre-embryos in a cycle using exogenous steroids without prior gonadotrophin-releasing hormone agonist suppression yields favourable pregnancy results.

We have analysed the use of a programmed cycle of administration of exogenous steroids without prior suppression with a gonadotrophin-releasing hormone agonist (GnRHa) for the transfer of cryopreserved-thawed pre-embryos. From July 1992 to June 1994, 199 cycles (162 patients) were studied. Pre-embryos had been previously cryopreserved at the pronuclear stage using 1.5 M 1,2-propanediol as a cryoprotectant. Preparation of the endometrium was achieved in a step-up regime with transdermal oestradiol patches (0.1 to 0.4 mg). Progesterone in oil (50 mg i.m.) was started on cycle day 13. Pre-embryos were thawed on day 14 and transferred on day 15 after evidence of survival and cleavage. The mean (+/- SD) age of patients undergoing transfer was 35.4 +/- 4.3 years. The mean number of pre-embryos thawed was 4.7 +/- 1.8 with a mean of 3.3 +/- 1.4 pre-embryos being transferred. Eight of the cycles demonstrated follicular development >16 mm prior to thaw and transfer; however, these patients did not demonstrate a luteinizing hormone surge. Mean endometrial thickness on day 13 was 10.8 +/- 2.1 mm. Overall pregnancy rate was 29.2% (57/195). The ongoing or delivery rate was 16.1% (32/195). The rate of preclinical losses per transfer was 6.2% (12/195). Overall, the implantation rate was 6.2% (47/757). Thus, the use of a programmed cycle for cryopreserved embryo transfer yields favourable pregnancy outcome and offers practical advantages to patients. Prior suppression with a GnRHa is not necessary for endometrial preparation.