1169例冻融胚胎移植周期的临床妊娠结局分析

目的探讨影响冻融胚胎移植(FET)妊娠结局的相关因素。方法回顾分析2017年1月至2019年12月在深圳市妇幼保健院行FET的1169对夫妇的临床数据,采用单因素分析和Logistic多因素回归分析探讨FET妊娠结局的相关因素。结果1169个FET周期的临床妊娠率为50.13%;单因素分析表明,年龄>35岁、不孕年限>6年显著降低胚胎种植率和临床妊娠率(P<0.01),但囊胚或多个优胚数目移植可提高胚胎种植率和临床妊娠率(P<0.01);移植多个胚胎提高胚胎种植率(P<0.05),但子宫内膜厚度>12 mm提高临床妊娠率(P<0.05)。多因素Logistic回归分析显示年龄增加和优胚移植数目减少是临床妊娠率的危险因素(P<0.01)。结论患者年龄和移植优胚数目是影响FET的主要因素;年龄增加是临床妊娠结局的危险因素。     

High serum oestradiol concentrations in fresh IVF cycles do not impair implantation and pregnancy rates in subsequent frozen-thawed embryo transfer cycles

High oestradiol concentrations may be detrimental to the success of in-vitro fertilization (IVF) treatment. A total of 1122 women aged <40 years who were undergoing their first IVF cycle were evaluated retrospectively. Serum oestradiol concentrations on the day of human chorionic gonadotrophin (HCG) administration were categorized into three groups: group A <10 000 pmol/l; group B 10 000-20 000 pmol/l and group C >20 000 pmol/l. In fresh cycles, group A had significantly lower pregnancy rates per transfer (16.2 versus 23.7% respectively, P = 0.005, chi(2)) and implantation rates (8.7 versus 11.7% respectively, P = 0.037, chi(2)), when compared with group B. The pregnancy rate per transfer in group C was significantly lower than that in group B (12.1 versus 23.7%, P = 0.049, chi(2)) and group C had the lowest implantation rate (6.4%). In frozen-thawed embryo transfer cycles, implantation rates in groups A, B and C were similar (7.5, 8.1 and 9.6% respectively) and the pregnancy rates were also comparable in all groups. In conclusion, high serum oestradiol concentrations in fresh IVF cycles may adversely affect implantation and pregnancy rates. Embryo quality seemed unaffected as excess embryos from different groups had similar implantation and pregnancy rates in frozen-thawed embryo transfer cycles. The reduced implantation was probably due to an adverse endometrial environment resulting from high serum oestradiol concentrations.     

The usefulness of ultrasound guidance in frozen-thawed embryo transfer: a prospective randomized clinical trial

BACKGROUND: Recent randomized controlled trials have shown that implantation and pregnancy rates were improved with ultrasound-guided embryo transfer compared with clinical touch in fresh IVF cycles associated with supraphysiological ovarian steroid levels. However, the usefulness of ultrasound guidance in frozen-thawed embryo transfer where potential hormonal influences are lacking has not been appropriately investigated. METHODS: A total of 184 consecutive patients undergoing thawed embryo transfer cycles with hormone replacement under pituitary suppression were randomized by computer-generated randomization table to two study groups: 93 had ultrasound-guided (group 1) and 91 had clinical touch (group 2) embryo transfer. RESULTS: There was equal distribution between the two study groups with respect to the main demographic and baseline characteristics of the patients as well as the characteristics of both prior IVF cycles from which embryos were generated and cryopreserved-thawed embryo transfer cycles. However, both pregnancy and implantation rates in group 1 (34.4 and 19.8% respectively) were significantly higher than the corresponding values (19.7 and 11.9%) in group 2. CONCLUSIONS: Ultrasound guidance in frozen-thawed embryo transfer significantly increases pregnancy and implantation rates.     

Ovulation side and cycle fecundity: a retrospective analysis of frozen/thawed embryo transfer cycles

The aim of the study was to evaluate a possible lateral difference in ovarian activity and its effect on cycle fecundity. A database was analysed retrospectively which covered 477 cycles in which frozen/thawed embryo transfer had been carried out. The cycles were spontaneous, with no hormonal treatment. Women with ovulation problems as a reason for infertility treatment were excluded. Factors investigated were the side of ovulation, endometrial thickness on cycle days 10-12 and on the day of embryo transfer, and pregnancy rate per embryo transfer. Ovulation was right-sided in 273 of the 477 cycles (57.2%) and left-sided in 204 of the cycles (42. 8%) (95% CI 38.3-47.2, P = 0.002). In the age category of 30-37 years, covering 288 cycles, the incidence of left-sided ovulation was 126 (43.7%, 95% CI 38.0-49.5, P = 0.034). In this category, the endometrial thickness (+/-SD) was significantly greater on the day of embryo transfer (i.e. at time of implantation) when there had been left-sided ovulation compared with right-sided [9.6 mm (2.0) versus 9.1 mm (1.8), P = 0.037]. In addition, the pregnancy rate per embryo transfer was higher when ovulation had been on the left side [32/126 (25.2%) versus right side 24/162 (14.8%), P = 0.035, 95% CI 0.0122-0.199]. In conclusion, right-sided ovulation was more frequent than left-sided in the whole group. This is the first study to report that the side of ovulation has a clinical impact. These data support the hypothesis that the side of ovulation is significant in terms of embryo implantation.     

Prospective evaluation of simple morphological criteria for embryo selection in double embryo transfer cycles

Preventing the occurrence of high-rank multiple pregnancieswithout reducing the pregnancy rate remains a high priorityof in-vitro fertilization and embryo transfer programmes. Ourprevious study demonstrated that, if there is at least one embryowith a good morphological grade, then the transfer of two (adouble embryo transfer) instead of three embryos does not resultin a lower pregnancy rate, and that the influence of the numberof embryos transferred becomes significant only when poor-qualityembryos are transferred. This result allowed us to employ thesimple policy of systematically selecting double embryo transfercycles without affecting the pregnancy rate. Since January 1994,when patients <37 years of age had more than two embryosavailable for transfer, only two instead of three embryos weretransferred if at least one of the embryos demonstrated a goodmorphological grade. After a 1 year application of this policy,of the 147 cycles (group A) that fulfilled the above criteria,two embryos were transferred in 92 cycles, while three embryoswere transferred in the other 55 cycles. The results of thesecycles were compared to those of the control 144 cycles (groupB) in which three embryos were transferred, prior to the applicationof this policy. The on-going pregnancy rates and the incidenceof multiple and triplet pregnancies were 24% and 28%, 22% and23%, and 2% and 9% in groups A and B respectively. The rateswere not significantly different. In conclusion, although ourprospective trial demonstrated a tendency of decreasing pregnancyrate and an invariable incidence of multiple pregnancies, thevery low occurrence of triplets during this period indicatedthat this policy provided a practical compromise between achievinga high pregnancy rate and an acceptable incidence of tripletpregnancies.     

Pregnancy: Serum concentrations of luteinizing hormone and progesterone in ovum recipients: their relationship with pregnancy and miscarriage

Our objective was to test the hypothesis that the associationbetween elevated luteinizing hormone (LH) concentrations andmiscarriage is mediated via an effect of LH on the maternalenvironment, rather than on the oocyte. The impact of maternalage, ovarian function, previous IVF attempts, therapeutic (buserelin)and hormonal (LH, oestradiol, progesterone) effects occurringon the day of zygote intra-Fallopian transfer (ZIFT) or embryotransfer, and of oocyte or embryo numbers, whether they werefresh or frozen, and their mode of transfer on the occurrenceof pregnancy and miscarriage following ovum donation (n = 57)were investigated. The cycles were divided by outcome into non-pregnant(n = 26), miscarriage (n = 19) and normal term pregnancy (n= 12). The circulating concentrations of LH were greater inmiscarriage cycles (P = 0.046) and cycles ending in pregnancy(P = 0.04) than in non-pregnant cycles, while the concentrationsof progesterone were greater in non-pregnant (P = 0.029) andmiscarriage (P = 0.015) cycles than in cycles ending in pregnancy.Frozen embryos were used more frequently in non-pregnant comparedto cycles ending in pregnancy (P = 0.016). Multiple regressionanalysis was used to investigate which factors are associatedwith miscarriage and identified progesterone concentrationsat the time of transfer as being the only significant variable(r = 0.48, F = 8.5, P = 0.007). The same method of analysiswas used to investigate which factors are associated with thefailure to conceive and identified previous IVF attempts (F= 5.8, P = 0.021), the presence of ovarian function (F = 5.7,P = 0.022), the use of frozen zygotes (F = 5.1, P = 0.029) andprogesterone concentrations (F = 5.9, P = 0.02), with an overallresult of r = 0.59, F = 5.2 and P = 0.002. In conclusion, highprogesterone concentrations were associated with the failureto conceive and miscarriage. In contrast, LH concentrationswere lower in women who failed to conceive but similar in pregnantwomen who did and did not miscarry. This suggests that the associationbetween elevated LH concentrations and infertility is via adirect effect of LH on the oocyte and an indirect effect, mediatedby elevated progesterone concentrations, on the endometrium.     

Influence of position and length of uterus on implantation and clinical pregnancy rates in IVF and embryo transfer treatment cycles

In a prospective study of 807 consecutive women shown to have an apparently normal uterus after hysterosalpingography, hysteroscopy or pelvic ultrasonography prior to IVF or intracytoplasmic sperm injection (ICSI) and embryo transfer, the position and length of the uterine cavity was measured routinely at a pre-treatment mock transfer procedure. The apparent length of the uterine cavity was <7 cm in 128 women (group 1), 7-9 cm in 594 women (group 2) and >9 cm in 85 women (group 3). The uterus was noted to be retroverted in 38. 2% (308) women. The embryo transfer catheter was advanced to 5 mm from the uterine fundus based on the previously determined cavity length in all the embryo transfer procedures at 48 h after oocyte collection. Implantation and clinical pregnancy rates were not significantly different with respect to position of the uterus, difficulties encountered in passage of the catheter, mean age of the women, aetiology or duration of infertility or embryology events. An apparently greater cavity length was seen in older and/or parous women, but the difference was not statistically significant. Although the highest implantation and clinical pregnancy rates were seen in women with a cavity length of 7-9 cm (group 2) the differences were not statistically significant: group 1, 18.9 and 36. 7%; group 2, 21.0 and 46.5%; and group 3, 17.3 and 32.9% respectively. The incidence of ectopic pregnancy per reported clinical pregnancy was highest in group 1 women, being 14.9% (7/47) in comparison with group 2 (1.8%, 5/276) and group 3 (0%, 0/27) (P: < 0.0005), suggesting that the size of the uterus is a critical factor in the aetiology of ectopic pregnancy in IVF/ICSI-embryo transfer.     

Serum progesterone at the time of human chorionic gonadotrophin does not predict pregnancy in in-vitro fertilization and embryo transfer

Controversy exists as to whether the serum concentration ofprogesterone on the day of human chorionic gonadotrophin (HCG)administration following ovarian stimulation for in-vitro fertilization(IVF) and embryo transfer can be used to predict the likelihoodof success. This retrospective study was undertaken to answerthis question by analysing a large population of IVF and embryotransfer cycles (n = 756). In addition to the concentrationof progesterone on the day of HCG administration, all variablesknown to impact on IVF and embryo transfer success (such aspatient age), indication for IVF and embryo transfer, numberof oocytes retrieved and the number of embryos generated andtransferred were examined. There was a significant increasein the number of oocytes retrieved with increasing progesteroneconcentration at the time of HCG administration. However, therewas no correlation of progesterone concentration at HCG administrationwith pregnancy and implantation rates. It is concluded thatprevious reports associating a slight elevation of progesteronein gonadotrophin- releasing hormone agonist ovarian stimulationcycles for IVF and embryo transfer may be misleading becauseof a small sample size or the presence of confounding variablesthat affect IVF and embryo transfer success.     

The impact of the embryo transfer catheter on the pregnancy rate in IVF

BACKGROUND: The aim was to assess whether the type of embryo transfer set used for embryo transfer affects the ongoing pregnancy rate in IVF. METHODS: The TDT set was compared with the K-soft 5000 in a large, prospective, randomized study. Patients were randomized moments before transfer by drawing a consecutively numbered, sealed, opaque envelope indicating the catheter to be used. RESULTS: 2059 embryo transfers in 1296 patients were analysed. The ongoing pregnancy rate was significantly higher in the K-soft group. If the first transfer of a patient (n = 1296) within this study period was analysed, the ongoing pregnancy rates were 27.1 versus 20.5% (P = 0.006). If the analysis is limited to patients that underwent their very first transfer ever (n = 607), the ongoing pregnancy rates were 30.3 versus 20.0% (P = 0.003) in favour of the K-soft. CONCLUSION: We conclude from these data that the type of embryo transfer set used for embryo transfer does affect the ongoing pregnancy rate and that the impact of the variable transfer catheter on the ongoing pregnancy rate increases when the a priori chance of pregnancy increases.     

Biochemical monitoring during hormone replacement therapy cycles for transfer of cryopreserved embryos in patients with functional ovaries.

Biochemical monitoring was undertaken in 22 treatment cycles for women with normal ovarian function who underwent pituitary suppression with buserelin and administration of exogenous oestradiol (E2) and progesterone (P) for cryopreserved embryo transfer (ET). Eighteen transfers of 1-4 thawed embryos, on the third day of exposure to progesterone, resulted in five clinical pregnancies (27.8%) and one biochemical pregnancy. There was no difference between pregnant and non-pregnant patients in the number and quality of embryos transferred, age, weight or infertility diagnosis. Serum E2 level from days 10-17 (the late proliferative phase) of the therapy cycle were significantly higher in the pregnant group compared with the non-pregnant group (P less than 0.05--P less than 0.005). There were no significant differences in P levels between the two groups from the onset of progesterone administration to the end of the cycle. However, as might be expected, the mean E2/P molar ratio in the pregnant group was significantly higher at the time of ET (P less than 0.02). It is concluded that biochemical monitoring during the embryo replacement cycle is necessary to tailor drug dosages for individual requirements to achieve adequate E2 levels before ET. Alternative routes of oestradiol administration need to be considered in patients with poor E2 profiles.     

Profound LH suppression after GnRH antagonist administration is associated with a significantly higher ongoing pregnancy rate in IVF

BACKGROUND: The significance of suppressed LH levels in GnRH antagonist cycles for IVF outcome is currently unknown. The purpose of this study was to evaluate prospectively the association between LH levels and ongoing pregnancy achievement after GnRH antagonist initiation in IVF cycles. METHODS: Ovarian stimulation with a fixed dose of 200 IU recombinant FSH and daily GnRH antagonist (ganirelix) 0.25 mg from day 6 of stimulation was initiated in 116 women. Patients were not pretreated with an oral contraceptive. Induction of final oocyte maturation was performed with HCG 10,000 IU as soon as three follicles of > or =17 mm were present in ultrasound, and was followed by oocyte pick-up, conventional IVF or ICSI, and embryo transfer. The luteal phase was supplemented with vaginal progesterone. RESULTS: A significant decrease of both ongoing pregnancy rate and implantation rate was present across groups of patients with increasing LH levels. The highest implantation rate and ongoing pregnancy rate was present in those patients with LH levels on day 8 of stimulation < or =0.5 IU/l. CONCLUSIONS: Profound suppression of LH on day 8 of stimulation is associated with a significantly higher chance of achieving an ongoing pregnancy. More studies are necessary to evaluate this phenomenon further.     

The use of intra-endometrial embryo transfer for increasing the pregnancy rate

It has been demonstrated previously that pregnancy can be achievedby the direct insertion of embryos into the endometrial stroma(intra-endometrial embryo transfer) of mice. In this study weevaluated whether intra-endometrial transfer resulted in a higherpregnancy rate than conventional embryo transfer. Mouse blastocysts(ICR strain), recovered on day 4 of pregnancy, were transferredinto pseudopregnant day 2, day 3 and day 4 mice of the samestrain; 1-, 2- and 8-cell embryos were also transferred intopseudopregnant day 4 mice. In intra-endometrial embryo transfer,a 27 gauge injection needle was inserted near the utero-tubaljunction into the endometrial stroma and then removed; one blastocystwas transferred into each uterine horn with a glass micropipette.Conventional transfers were performed simultaneously as controls.The pregnancy rates and embryonic viability rates were evaluated9 days after embryo transfer. Furthermore, the rates of livebirth for intra-endometrial and conventional embryo transferswere compared when blastocysts were transferred into pseudopregnantday 4 uteri by both methods. In the transfer to pseudopregnantday 2 recipients, the pregnancy and embryonic viability rateswere significantly higher (P < 0.01) in intra-endometrial[23.4 (11/47) versus 15.9% (15/94)] than in conventional embryotransfer [4.3 (2/46) versus 2.2% (2/92)]. In the transfer topseudopregnant day 3 recipients, both rates were also higher(P < 0.01) in intra-endometrial [90.9 (40/44) versus 87.5%(77/88)] than in conventional transfer [67.4 (31/46) versus64.1% (59/ 92)]. In synchronous transfer to pseudopregnant day4 recipients, there was no difference between methods in thepregnancy rate [conventional, 48.9% (24/49); intraendometrial,50.9% (29/57)] and the embryonic viability rate [conventional,44.9% (44/98); intra-endometrial, 43.0% (49/114)]. In the transferof 1-, 2- and 8-cell embryos into pseudopregnant day 4 mice,pregnancy and embryonic viability rates were very low in bothtransfer methods. Intra-endometrial transfer produced normalliving offspring at a similar rate to conventional transfer.These results reveal that intra-endometrial transfer increasespregnancy and embryonic viability rates in asynchronous embryotransfer in mice, especially when the duration of pseudopregnancyin the recipients was less than the age of the transferred embryos.     

Successful non-surgical management of a heterotopic abdominal pregnancy following embryo transfer with cryopreserved-thawed embryos.

Heterotopic pregnancy is an increasingly common complication of assisted reproductive technology. Abdominal pregnancy is a rare and life-threatening form of ectopic pregnancy that can present as the extrauterine portion of a heterotopic pregnancy. We present the case of a cryopreserved-thawed embryo transfer that resulted in a simultaneous intrauterine and abdominal pregnancy first recognized at 10 weeks gestation. Ultrasound-guided transvaginal injection of potassium chloride into the abdominal pregnancy resulted in asystole and spontaneous resorption of the ectopic fetus, while the intrauterine pregnancy continued and resulted in a liveborn vaginal delivery at full term. Selective embryo reduction using a non-surgical approach in a haemodynamically stable patient can therefore be considered in the management of heterotopic abdominal pregnancy if diagnosed relatively early.     

Impact of elective single embryo transfer on the twin pregnancy rate

BACKGROUND: It is unclear how the implementation of elective single embryo transfer in clinical practice would affect clinical pregnancy and delivery rates and multiple birth rates. METHODS: This retrospective study analysed 1871 IVF/ICSI cycles carried out from 1997 to 2001 in the IVF programme of a single university infertility clinic. RESULTS: The number of elective single embryo transfers increased from 11 to 56%. At the same time the clinical pregnancy rate was relatively stable; mean 34.0% (range 28-42). The number of embryos per embryo transfer decreased from 1.8 to 1.3. The multiple pregnancy and delivery rates dropped markedly from 25 to 7.5% and from 25 to 5% respectively. CONCLUSIONS: An elective single embryo transfer programme can be adopted in daily practice that decreases the twinning rate to <10% and does not affect the overall pregnancy rate.     

Single embryo transfer in preimplantation genetic diagnosis cycles for women <36 years does not reduce delivery rate

BACKGROUND: The Belgian legislation imposes single embryo transfer (SET) on women of <36 years in their first treatment cycle to avoid multiple pregnancies. The aim of this study is to assess the impact of this legislation on the outcome of preimplantation genetic diagnosis (PGD) for inherited diseases in young women undergoing SET. METHODS: A retrospective analysis of PGD cycles for monogenic disorders and translocations in women <36 years on their first treatment cycle. Two groups of patients were defined according to the implementation of the Belgian legislation: (i) double embryo transfer (DET), January 2001-June 2003 (ii) SET, July 2003-June 2005. The primary and secondary outcome measures were delivery per embryo transfer and multiple pregnancy rates, respectively. A subgroup analysis for monogenic disorders and translocations was performed. RESULTS: 62 cycles were included in the DET group and 73 cycles in the SET group. The mean age, number of cumulus-oocyte complexes, number of fertilized oocytes, number of biopsied and cryopreserved embryos were comparable between both groups. There was no significant difference in the delivery rates between the DET and the SET groups (33.9% versus 27.4%, respectively). Multiple pregnancies were avoided when SET was performed. When monogenic disorders and chromosomal translocations were separately evaluated, no significant difference in the delivery rate after SET was observed. CONCLUSIONS: The implementation of a SET policy in young women undergoing PGD for monogenic disorders and translocations enables a significant reduction of multiple pregnancies without significantly affecting the delivery rate.     

Luteal phase ovarian oestrogen is not essential for implantation and maintenance of pregnancy from surrogate embryo transfer in the rhesus monkey

The aim of this study was to investigate whether luteal phaseovarian oestrogen is required for blastocyst implantation andpregnancy maintenance in the rhesus monkey. Preimplantationembryos were retrieved from naturally ovulated, mated embryodonor monkeys. In group I, developmentally normal, age- andstage-matched embryos were transferred to recipient monkeysshowing naturally synchronized ovulatory cycles. Immediatelyprior to embryo transfer, recipients were subjected to bilateralovariectomy, and following transfer they were treated with i.m.injections of either progesterone (group Ia, n= 4), or oestradiol+ progesterone (group Ib, n= 2). Recipient monkeys of groupIc (n= 4) were subjected to sham ovariectomy and vehicle injection.In group Ia, progesterone supplementation alone led to threepregnancies and live births. In group Ib, there was one livebirth. In the control group Ic, four transfers resulted in twolive births and one abortion on cycle day 58. Analysis of serumprogesterone and oestradiol profiles showed that oestradiolhad declined to undetectable levels within 3–5 days afterovariectomy in group Ia recipients, and the area under the curveof serum oestrogen concentrations during the peri-implantationperiod (days 10–20 after ovulation) were less (p< 0.001)in group Ia compared with group Ic. There were no changes inthe area under the curve among serum progesterone concentrationsin all the subgroups. In group II, long-term ovariectomizedembryo recipients (n= 4) were primed with oestradiol till cycleday 11 of simulated transfer cycle, and received progesteronetreatment from cycle day 10 till the end of the experiment.Of four transfers, live births were recorded in two cases, whilein one case abortion occurred on cycle day 66. Serum oestradiolconcentrations were undetectable during the presumptive peri-implantationperiod of pregnancy cycles in group II recipient monkeys. Noyes‘dating of endometrial samples collected from both groups ondays 5–7 after the oestrogen rise revealed that endometrialhistology synchronized well with those found during days 3–5after ovulation in normal menstrual cycle. We conclude thatluteal phase ovarian oestrogen is not essential for progesterone-dependentendometrial receptivity and response leading to implantationand pregnancy maintenance in the rhesus monkey.     

Elective single day 3 embryo transfer halves the twinning rate without decrease in the ongoing pregnancy rate of an IVF/ICSI programme

BACKGROUND: Data on the effect of elective single embryo transfer (eSET) on the total and multiple pregnancy rates of an IVF/ICSI programme are reported. METHODS AND RESULTS: A retrospective cohort analysis of eSET was carried out over a 4 year period. A total of 1559 cycles resulted in 1464 transfers; 299 transfers of one top quality embryo (20.4%) and 86 of one non-top quality embryo (5.9%) yielded 149 conceptions (49.8%) with 105 ongoing pregnancies (35.1%) and 26 conceptions (30.2%) with 19 ongoing implantations (22.1%) respectively; 1079 transfers of two (n = 853; 58.3%) or more than two (n = 226; 15.4%) embryos yielded 366 ongoing pregnancies (33.9%). The ongoing pregnancy rates for the years between 1998 and 2001 were 35.9, 27.9, 31.9 and 31.0% per oocyte retrieval and 38.5, 29.4, 34.1 and 33.2% per transfer. There were no differences in pregnancy rates between any of the years. The average ongoing pregnancy rate (>12 weeks) over the 4 years was 31.5% per started cycle and 33.5% per transfer; the average number of embryos transferred decreased from 2.26 (1998) to 1.79 (2001); the multiple pregnancy and twinning rates dropped from 33.6 and 29.5% (1998) to 18.6 and 16.3% (2001) respectively. CONCLUSIONS: Judicious application of eSET can halve the twinning rate while maintaining the overall pregnancy rate.     

Lack of placental protein 14 production in pregnancy after frozen embryo transfer, down-regulation of anterior pituitary and administration of exogenous oestradiol and progesterone

The circulating levels of placental protein 14 (PP14) and progesterone were measured in three pregnancies resulting from the transfer of cryopreserved embryos. Two of these women had suppressed ovarian activity as a result of pituitary down-regulation with the luteinizing hormone-releasing hormone agonist (buserelin) prior to treatment with exogenous oestradiol and progesterone. After 14 days of oral oestradiol treatment and if the endometrial thickness was greater than 7 mm, progesterone was given intramuscularly for a further 14 days with embryo transfer on the third day of this treatment. On confirmation of pregnancy by human chorionic gonadotrophin analysis, progesterone administration was altered to transvaginal pessaries for maintenance of adequate progesterone levels and endometrial support. In the two women with ovarian suppression, PP14 levels remained below the 2.5th centile of the normal range for pregnancy. In the third pregnancy, embryo transfer was performed 3 days after a spontaneous luteinizing hormone surge in a normal menstrual cycle. In this pregnancy, PP14 levels were within the normal range. Ultrasonic examination confirmed three normal ongoing singleton pregnancies. These results suggest that the majority of PP14 production in normal pregnancy is under ovarian or anterior pituitary control and that the influence of progesterone is of a secondary nature.     

Ultrasound-guided embryo transfer improves pregnancy rates and increases the frequency of easy transfers

BACKGROUND: Recent reports have suggested that ultrasound (US) guidance during embryo transfer might improve pregnancy rates. METHODS: A prospective randomized (computer-generated random table) trial was performed to compare embryo transfer under abdominal US guidance (n = 255 women) with clinical touch embryo transfer (n = 260). RESULTS: The clinical pregnancy rate was 26.3% (67/255) in the US-guided transfer group compared with 18.1% (47/260) in the clinical touch transfer group (P < 0.05). The implantation rate was 11.1% (100/903) in the US group compared with 7.5% (66/884) in the clinical touch group (P < 0.05). US-guided transfer was associated with a decrease in the difficulty of the transfers: 97% of transfers were easy in the US-guided group compared with 81% in the clinical touch group (P < 0.05). CONCLUSIONS: US-guided embryo transfer increased pregnancy and implantation rates in IVF cycles, as well as the frequency of easy transfers. It is suggested that the decrease in cervical and uterine trauma can play a role in the increase in pregnancy rates associated with US-guided transfer. It is recommended that embryo transfer should be performed under US guidance.     

Elective transfer of one embryo results in an acceptable pregnancy rate and eliminates the risk of multiple birth.

To avoid multiple pregnancies without compromising pregnancy rates (PR) is a challenge in assisted reproduction. We have compared pregnancy results among 74 elective one-embryo transfers (group 2) and 94 transfers where only one embryo was available (group 1). All the fresh embryo cycles during 1997 in two clinics in Helsinki were analysed, and cumulative PR among these couples after frozen-thawed embryo transfers up to June 1998 were counted. In group 2, where at least two embryos were available for transfer, and only one was transferred on day 2 or 3, the PR per embryo transfer was 29.7%. In group 1, the PR per embryo transfer was 20.2%. In group 2, the cumulative PR after frozen-thawed embryo transfers was 47.3% per oocyte retrieval. Over the same time, 742 two-embryo transfers were carried out. The PR per embryo transfer was 29.4% in these subjects, but 23.9% of these pregnancies were twins. The implantation rates, as well as the PR, were highest when the embryos were at the four- to five-cell stage on day 2 (35.8 versus 9.7% compared with the two- to three-cell stage, P < 0.001) or at the six- to eight-cell stage on day 3 (45.5%). The PR per embryo transfer was higher when a grade 1 or 2 embryo was transferred compared with a grade three embryo (34. 0 and 26.7% versus 8.8% respectively, P < 0.05). In women 35 years or younger, the PR per elective one-embryo transfer was 32.8%. The corresponding figure in women older than 35 years was 18.8%. On the basis of these results, elective one-embryo transfer can be highly recommended, at least in subjects who are younger than 35 years of age, and who have grade one or grade two embryos available for transfer.