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1.
Reprod Biomed Online ; 20(2): 182-90, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20113956

ABSTRACT

To identify baseline characteristics related to successful ovulation induction, data were analysed from oligo- or anovulatory patients undergoing their first cycle of human recombinant FSH (r-hFSH; follitropin alfa) in a chronic low-dose (75 IU starting dose), step-up protocol in two clinical trials (n=446). Patients were grouped according to response: group A, ovulated within 14 days (75 IU follitropin alfa); group B, ovulated after 14 days (>75 IU follitropin alfa); group C, not administered human chorionic gonadotrophin (HCG) because of poor response; group D, cycle cancelled due to over-response (HCG not administered); group E, spontaneous ovulation prior to obtaining criteria for administration of HCG. Mean body mass index (BMI) of group A (25.0 kg/m(2)) was significantly lower than groups B (27.1 kg/m(2), P<0.001) or C (28.2 kg/m(2), P<0.0001), but similar to group D (24.3 kg/m(2)). Mean antral follicle count (AFC) of group A was also significantly lower than group C (18.3 versus 22.7; P=0.018), but not significantly different from groups B (21.5) or D (19.5); group E had the highest mean AFC (35.7). Comparatively low BMI, low AFC and higher (although still within the normal range) FSH concentration at baseline were associated with successful ovulation induction in infertile women undergoing a chronic low-dose, step-up stimulation protocol.


Subject(s)
Infertility, Female/drug therapy , Ovulation Induction/methods , Ovulation/drug effects , Adult , Anovulation/drug therapy , Chorionic Gonadotropin/administration & dosage , Chorionic Gonadotropin/therapeutic use , Female , Follicle Stimulating Hormone/administration & dosage , Follicle Stimulating Hormone/blood , Follicle Stimulating Hormone/therapeutic use , Glycoprotein Hormones, alpha Subunit/administration & dosage , Glycoprotein Hormones, alpha Subunit/therapeutic use , Humans , Multicenter Studies as Topic , Ovarian Follicle/drug effects , Pregnancy , Randomized Controlled Trials as Topic , Treatment Outcome , World Health Organization
2.
Fertil Steril ; 63(5): 1121-4, 1995 May.
Article in English | MEDLINE | ID: mdl-7720929

ABSTRACT

OBJECTIVE: To determine if sperm could be manipulated to be a noninvasive transport carrier for the delivery of gene fragments to the blastocyst. DESIGN: Sperm cells carrying foreign DNA fragments from human papillomavirus (HPV) types 16, 18, 31, and 33 were allowed to migrate from one end of an artificial reproductive tube and to come in contact with hatching mouse blastocysts at the other end of the tube. The blastocysts were then washed and analyzed for the presence of the foreign DNA fragments. SETTING: Clinical and academic research environment. MAIN OUTCOME MEASURE: Detection of amplified products from transferred foreign DNA using the polymerase chain reaction and primers targeted at the E6-E7 region for different HPV types. RESULTS: Polymerase chain reaction analyses showed transference of DNA HPV type 18 to the blastocysts. Not all types of DNA fragments were transferred equally. CONCLUSION: The results suggested the possibility of using sperm as a noninvasive gene delivery system for passing on gene fragments to preimplantation embryos. It was demonstrated that certain DNA fragments were easier to deliver than others, indicating the necessity for exploring all the factors involved in the mechanism of the transference process. The study also serves to highlight the possibility of unintentional transmission of viral or bacterial DNA to the developing embryo via the sperm.


Subject(s)
Blastocyst/metabolism , Gene Transfer Techniques , Genetic Vectors , Spermatozoa , Animals , DNA Primers , DNA, Viral/analysis , Female , Male , Mice , Papillomaviridae/genetics , Polymerase Chain Reaction
3.
Fertil Steril ; 62(3): 624-9, 1994 Sep.
Article in English | MEDLINE | ID: mdl-8062960

ABSTRACT

OBJECTIVE: To evaluate the titanium Kirsch-Zhu microclip microsurgical reanastomoses of the fallopian tubes. DESIGN: Compare the reanastomoses of the rat uterine horn between Kirsch-Zhu clips (Cushman Engineering, Albuquerque, NM) (group A) and conventional suture microsurgical techniques (group B). SETTING: Microsurgery Research Laboratory, Loma Linda University Medical Center, Loma Linda, California. PATIENTS, PARTICIPANTS: Fifteen SD rats Harlan (Harlan Sprague-Dawley Corp., Indianapolis, IN) were done in groups A and B and six in control group (C). MAIN OUTCOME MEASURE: Pregnancy rate, litter size, tissue of procedure, and histologic results. RESULTS: The clip technique was shorter in procedure time and resulted in equal fertility rate and litter size. Histologically, there were less granulomatous formation and histiocytic inflammation, but muscularis thinning and fibrosis were noted with the clip. CONCLUSIONS: The Kirsch-Zhu clip has potential for application to human fallopian tube reanastomoses.


Subject(s)
Anastomosis, Surgical/instrumentation , Fallopian Tubes/surgery , Animals , Equipment Design , Fallopian Tubes/pathology , Female , Intraoperative Period , Microsurgery , Postoperative Period , Pregnancy , Rats , Rats, Sprague-Dawley , Sutures , Time Factors
4.
J Am Assoc Gynecol Laparosc ; 1(4 Pt 1): 395-400, 1994 Aug.
Article in English | MEDLINE | ID: mdl-9138882

ABSTRACT

A new method for reconstructing rat uterine horn was developed in which nonpenetrating, arcuate-legged clips are applied in interrupted fashion to everted seromuscular edges, forming an elastomeric flanged joint. This anastomosis has unusual physical and morphologic properties, with improved tissue healing and luminal restitution. Clipping is easier than suturing, and resulted in equivalent fertility rate (50-60%) and litter size. It also is associated with less granuloma formation and hystiocytic infiltration than suture. The new technique has the potential of endoscopic translation for human tubal reconstruction.


Subject(s)
Laparoscopes , Microsurgery/instrumentation , Surgical Stapling/instrumentation , Uterus/surgery , Anastomosis, Surgical/instrumentation , Anastomosis, Surgical/methods , Animals , Chi-Square Distribution , Disease Models, Animal , Female , Postoperative Complications/pathology , Pregnancy , Pregnancy Outcome , Rats , Rats, Sprague-Dawley , Reference Values , Statistics, Nonparametric , Surgical Instruments , Surgical Stapling/methods , Uterus/anatomy & histology , Wound Healing/physiology
5.
Fertil Steril ; 61(5): 982-5, 1994 May.
Article in English | MEDLINE | ID: mdl-8174743

ABSTRACT

The present study demonstrated the presence of HPV gene sequences in Percoll-washed sperm cells using polymerase chain reaction primers targeting smaller gene regions. Up to 64% of the sperm specimens were shown to contain gene sequences indicative of the presence of HPV. Human papillomavirus type 16 was detected about twice as often as HPV type 18. The results suggest the possible role of sperm as a vector for HPV.


Subject(s)
DNA, Viral/analysis , Genes, Viral , Papillomaviridae/genetics , Spermatozoa/chemistry , DNA, Viral/genetics , Humans , Male , Papillomavirus Infections/transmission , Polymerase Chain Reaction , Tumor Virus Infections/transmission
6.
Fertil Steril ; 61(5): 986-9, 1994 May.
Article in English | MEDLINE | ID: mdl-8174744

ABSTRACT

The presence of high numbers of peroxidase-positive PML in ejaculated semen significantly reduced sperm HA, an important step leading to sperm capacitation. Sperm membranes at both the head and tail regions, as assessed by the hypo-osmotic viability parameter and the hypo-osmotic sperm swelling test, respectively, were not affected by peroxidase-containing leukocytes. Sperm motility was not affected, but sperm curvilinear and straight line velocity parameters were reduced in the presence of high concentrations of leukocytes in the ejaculate. The results suggested that the effect of leukocytes on sperm was through a reduction in sperm hyperactive motility but not through alterations in the sperm head and tail membranes.


Subject(s)
Leukocytes/cytology , Semen/cytology , Sperm Head/physiology , Sperm Motility/physiology , Sperm Tail/physiology , Cell Membrane/physiology , Cell Membrane/ultrastructure , Humans , Image Processing, Computer-Assisted , Male , Osmosis , Peroxidase , Sperm Head/ultrastructure , Sperm Tail/ultrastructure , Spermatozoa/cytology , Spermatozoa/physiology , Spermatozoa/ultrastructure
7.
Hum Reprod ; 9(2): 279-83, 1994 Feb.
Article in English | MEDLINE | ID: mdl-8027284

ABSTRACT

Heterodimer membrane glycoproteins expressed from hypervariable genes located in the histocompatibility linked antigen (HLA) class II genes on chromosome 6 have been shown to induce activation of lymphocytes and are involved in human sperm binding processes. The objective was to identify an association between HLA-DQA1, -DRB1 or -DPB1 genes and sperm kinematic parameters and sperm penetration of oocytes. The results showed reduced sperm hyperactivation and decreased sperm penetration of zona-free oocytes when the HLA-DRB1 allele was present. The reduced hyperactive motility was not attributed to alterations in sperm kinematic parameters. In contrast, the HLA-DPB1 gene only affected sperm count, linearity of movement and sperm head dimensions. HLA-DQA1 had no effect on the sperm parameters. The data suggest a link between HLA-DRB1 and HLA-DPB1 genes and sperm concentration, sperm movement characteristics and fertilizing capacity.


Subject(s)
Genes, MHC Class II , Sperm-Ovum Interactions/genetics , Alleles , Chromosome Mapping , Computers , Female , Humans , Male , Sperm Motility/genetics
8.
Arch Androl ; 31(1): 63-7, 1993.
Article in English | MEDLINE | ID: mdl-8373288

ABSTRACT

The protocol for intrauterine insemination (IUI) involves sperm processing using different methods that have produced varying results. These sperm wash methods do not take into consideration the problems of the exact timing of ovulation and the requirements of sperm cells at different stages of capacitation. The objectives of this study were 1) to use the double method wash previously reported to produce a mixture of different populations of sperm cells and determine the pregnancy outcome after IUI and 2) to compare the sperm kinematic parameters after the double method wash with those after the centrifuge (or whole-population) wash method. Patients were divided into either the double method group (n = 119) or the centrifuge method group (n = 76). The Hamilton-Thorn HTM-C automated sperm motility analyzer (Hamilton-Thorn Research, Danvers, MA) was used to analyze sperm motility parameters. Pregnancy outcomes were evaluated after controlled ovarian stimulation and IUI. An almost 2-fold increase was seen in the pregnancy rate with the double method wash compared with the centrifuge method wash. Sperm motility and velocity were also enhanced in the double method wash groups. The results support the usefulness of the double method wash for the preparation of sperm for IUI.


Subject(s)
Insemination, Artificial, Homologous/methods , Spermatozoa , Female , Humans , Male , Pregnancy , Specimen Handling/methods
9.
J Assist Reprod Genet ; 9(6): 531-3, 1992 Dec.
Article in English | MEDLINE | ID: mdl-1338579

ABSTRACT

OBJECTIVE: The purpose of this study was to determine if oocytes were capable of taking up exogenous DNA such as human papillomaviral (HPV) DNA and evaluate the zona pellucida as a barrier to the entry of foreign DNA into the oocyte. METHODS: The experiment consisted of four groups of hamster oocytes exposed to HPV DNA fragments: Group A, zona-free oocytes (n = 5); Group B, oocytes with an intact zona pellucida (n = 5); Group C, oocytes fixed in 4% buffered formalin solution for 20 min (n = 5); and Group D, zona-free oocytes (n = 4). Group C oocytes served as an internal control to ensure adequate washing of the oocytes after incubation. RESULTS: The zona pellucida was not a barrier to foreign DNA molecules. The PCR did not detect L1-HPV and beta-globin gene sequences in the untreated hamster oocyte. Uptake of the smaller DNA fragments such as that amplified from the beta-globin region was independent of active oocyte cell processes. CONCLUSION: Oocytes cultured in vitro can passively take up exogenous DNA fragments. The results suggest a possible role of oocytes as vectors for foreign DNA.


Subject(s)
DNA, Viral/metabolism , Oocytes/metabolism , Papillomaviridae/chemistry , Polymerase Chain Reaction , Animals , Biological Transport , Cricetinae , DNA/metabolism , DNA, Viral/analysis , Female , Globins/genetics , Humans , Zona Pellucida/metabolism
10.
Int J Fertil ; 37(6): 373-7, 1992.
Article in English | MEDLINE | ID: mdl-1360460

ABSTRACT

Sperm hyperactivation motility characterized by wide oscillatory movements of the sperm head, nonlinear directions, and rapid motility with occasional star-shaped pattern of movement was measured during routine semen analyses prior to an in vitro fertilization procedure. The method consisted of diluting liquefied semen 1:20 with Ham's F-10 supplemented with processed human cord sera followed by incubation at 37 degrees C for 30 minutes. At the end of the incubation period, aliquots of semen samples were evaluated by phase contrast microscopy for sperm hyperactivation. The results indicated that (1) sperm samples exhibiting 15% or more hyperactive motility were associated with a significantly higher percent fertilization of oocytes during the IVF procedure; (2) sperm hyperactive motility was correlated to sperm fertilizability during IVF treatment cycles.


Subject(s)
Fertilization in Vitro , Sperm Motility/physiology , Female , Humans , Male , Pregnancy , Sperm-Ovum Interactions
11.
Fertil Steril ; 58(4): 841-4, 1992 Oct.
Article in English | MEDLINE | ID: mdl-1426337

ABSTRACT

In summary, the hypoosmotic viability parameter was significantly correlated with the outcome of the thawed sperm motility. The prefreeze supravital staining for sperm viability and the hypoosmotic sperm swelling test were not predictive of the thawed sperm total motility. The hypoosmotic viability parameter was not correlated to the postwarmed sperm motility after refrigeration. The results indicated that the integrity of the sperm membranes at the head were more important than the tail membrane.


Subject(s)
Cryopreservation , Spermatozoa/physiology , Cell Survival , Humans , Male , Osmosis , Sperm Motility
12.
Arch Androl ; 29(1): 43-8, 1992.
Article in English | MEDLINE | ID: mdl-1503523

ABSTRACT

Recently, there have been concerns regarding the presence of reactive oxygen species (ROS) produced during sperm processing for insemination. However, the sperm wash methods that yielded low ROS levels also had low sperm recovery after processing. The objective of this study was to compare sperm recovery after swim-up from pellet, overlay, and 2-layer Percoll wash methods with the recovery after the double method wash. The latter method consisted of a combination of 2 sperm wash methods, namely, the overlay and the Percoll method. Motile sperm were first collected through the overlay method. The leftover semen was then processed through the 2-layer Percoll method to scavenge motile sperm and the resultant pellet combined with the pellet from the overlay method. In this manner, the level of ROS was kept to a minimal, sperm recovery was improved, and a mixture of sperm with different surface properties was produced as a result of using different processing methods. The results indicated an improvement in sperm recovery and in total sperm motility in noncryopreserved sperm after using the double method wash when compared with the other wash methods. The study suggests that the double method wash is a feasible method for processing sperm for insemination.


Subject(s)
Cell Separation/methods , Spermatozoa/cytology , Cryopreservation , Humans , Male , Sperm Motility , Spermatozoa/physiology
13.
Andrologia ; 24(2): 77-81, 1992.
Article in English | MEDLINE | ID: mdl-1318647

ABSTRACT

Sperm nuclear decondensation is an integral step in fertilization which leads to the formation of the male pronucleus. The association between the in vitro spontaneous nuclear decondensation of human sperm and its fertilizing ability was studied in infertile male patients. The ability of sperm to fertilize an egg using the discontinuous two-layer Percoll method was significantly correlated to the percentage of decondensed swollen head (r = 0.43; P less than 0.005). The fertilizing ability of sperm processed with Test-Yolk buffer was correlated with the percentage of sperm at the fully decondensed stalk stage (r = 0.51; P less than 0.05). There were insignificant correlations for the whole-wash centrifugation, cryopreserved-thawed and swim-up methods. Samples of sperm that were positive (greater than 0% fertilization) in the sperm penetration assay had a higher percentage of decondensed sperm heads (66.7% vs. 20.6%) after Percoll wash or whole-wash centrifugation (60.5% vs. 44.3%) treatments compared with samples with no fertilization. Treatments that included Test-Yolk resulted in high percentages of decondensed swollen heads. The results suggest a positive association between sperm nuclear decondensation and the fertilizing ability of sperm, and affirm the importance of nuclear decondensation to the study of fertilization events.


Subject(s)
Cell Nucleus/physiology , Infertility, Male/physiopathology , Sperm Motility , Sperm-Ovum Interactions , Spermatozoa/physiology , Animals , Cell Nucleus/ultrastructure , Centrifugation, Zonal , Cricetinae , Cryopreservation , Female , Humans , Male , Oocytes/physiology , Povidone , Regression Analysis , Silicon Dioxide , Sperm Head/ultrastructure , Spermatozoa/ultrastructure
14.
Int J Fertil ; 37(2): 87-92, 1992.
Article in English | MEDLINE | ID: mdl-1349596

ABSTRACT

Hormonal changes induced during short-term administration of leuprolide were evaluated during the follicular phase in 57 patients who completed an IVF cycle. They were compared with those of 14 patients who were placed on long-term suppression. There was an unexpected abnormal increase in serum progesterone during the first week of the cycle in nine of the 57, with no significant change in the fertilization and cleavage rate; however, no pregnancy was achieved in this group. Transient mild elevation of progesterone was also detected in 16 patients with no adverse effect on fertilization and the outcome of the IVF. In the long protocol, the tonic levels of LH, FSH, and progesterone remained low throughout the follicular phase. The total number of pregnancies was higher in the short suppression regimen, but the full-term pregnancy rates were similar in both protocols.


Subject(s)
Fertilization in Vitro , Follicular Phase , Hormones/blood , Leuprolide/therapeutic use , Adult , Chorionic Gonadotropin/therapeutic use , Estradiol/blood , Female , Follicle Stimulating Hormone/blood , Humans , Luteinizing Hormone/blood , Pregnancy , Progesterone/blood
15.
Urology ; 39(1): 63-6, 1992 Jan.
Article in English | MEDLINE | ID: mdl-1728798

ABSTRACT

The sperm penetration assay (SPA) is subject to considerable variation, and controls are needed to verify the accuracy of the results. It is proposed that sperm hyperactivation (HA) can serve as a quality control check for the SPA. The objective was to determine if there was an association between the SPA outcome and sperm HA measured at various times during the SPA procedure. The data showed a significant correlation between percent sperm HA and percent zona-free oocyte penetration by sperm preincubated for three hours prior to sperm-oocyte interaction (short preincubation). Some sperm hyperactivity was observed in liquefied raw semen samples, but this was insignificantly related to SPA results. Low correlation was observed between SPA results and sperm HA determined immediately after centrifuge washing of sperm. The results suggest that it is possible to utilize sperm HA measured immediately after the sperm-oocyte interaction period as a quality control check of SPA results.


Subject(s)
Sperm Motility , Sperm-Ovum Interactions , Female , Humans , Male , Quality Control , Sperm-Ovum Interactions/physiology , Statistics as Topic
16.
Arch Androl ; 27(2): 103-8, 1991.
Article in English | MEDLINE | ID: mdl-1953194

ABSTRACT

The ubiquitous dinucleotide polyphosphate, diadenosine tetraphosphate (Ap4A), has been shown to be a signal molecule for DNA replication in mammalian cells. In this study, Ap4A and a related compound, diadenosine triphosphate (Ap3A), were tested for possible signaling functions in human spermatozoa. A computerized automated semen analyzer was used to detect changes in spermatozoa motility parameters. Cryopreserved-thawed donor spermatozoa were washed and incubated in 0.1 mM Ap4A, 0.1 mM Ap3A, or control medium. The data indicated that both Ap4A and Ap3A decreased the percentage of motile spermatozoa after 4 or more hours of incubation in vitro. The two dinucleotide polyphosphates caused an increase in the amplitude of lateral spermatozoa head displacement parameter only at the start of incubation. The other spermatozoa kinematic parameters were unaffected. No opposing ying-yang dual actions of Ap4A to Ap3A were seen. From the results, Ap4A and Ap3A were observed to be potential inhibitory signals of spermatozoa motility after prolonged exposure.


Subject(s)
Dinucleoside Phosphates/physiology , Signal Transduction , Sperm Motility , Spermatozoa/physiology , Humans , Image Processing, Computer-Assisted , In Vitro Techniques , Male , Photomicrography , Videotape Recording
17.
Hum Reprod ; 6(8): 1115-8, 1991 Sep.
Article in English | MEDLINE | ID: mdl-1725287

ABSTRACT

The parameter of sperm viability in hypoosmotic solution (VHOS) provides information concerning the membrane integrity of the sperm head. The objective of this study was to determine the association between the VHOS parameter and the sperm penetration assay. The VHOS parameter correctly predicted 70.0-71.4% of the failed sperm penetration assay samples in the short duration preincubation groups. A combination of both the VHOS parameter and the hypoosomotic sperm swelling (HOS) test significantly reduced the number of false negative results. In general, a sperm sample with an abnormal VHOS result and an abnormal HOS test result would be associated with a negative sperm penetration assay. Washing by centrifugation appeared to weaken the sperm head membranes while the swim-up method selected for sperm with strong head and tail membranes. After the various processing methods unique changes in the integrity of the sperm head and tail membranes for each sperm sample may help to identify the optimal method of preparation for individual patients undergoing the newer assisted reproductive technologies such as sperm microinjection.


Subject(s)
Cell Survival , Hypotonic Solutions , Spermatozoa/physiology , Staining and Labeling , Cell Membrane/physiology , False Negative Reactions , Female , Humans , Male , Sperm-Ovum Interactions , Spermatozoa/ultrastructure
18.
J In Vitro Fert Embryo Transf ; 8(1): 37-40, 1991 Feb.
Article in English | MEDLINE | ID: mdl-2016561

ABSTRACT

Semen analyses carried out as part of the clinical in vitro fertilization or intrauterine insemination protocols provide important information that determine the type of clinical treatment of the male partner and the sperm processing method. It is postulated that the sperm of male-factor patients cannot survive hypoosmotic stress conditions because of defective sperm membrane function. To test this, 0.1 ml of semen from each of 102 patients was placed in 1.0 ml of 150 mosmol/liter eosin citrate fructose solution and incubated for 30 min at 37 degrees C. The percentage viability of the sperm cells was then determined. The results indicated that patients with two or more abnormal semen parameters had a significantly lower percentage viability while in the hypoosmotic solution (40.6 +/- 4.7%), in contrast to non-male-factor patients (69.0 +/- 1.6%). Donor sperm (N = 32) serving as controls (73.3 +/- 2.1%) had a viability in hypoosmotic solution similar to that of non-male-factor patients. The data suggest that sperm of male-factor patients are less able to survive the hypoosmotic stress conditions as shown by the percentage viability in hypoosmotic solution and emphasize the importance of using less stressful sperm processing methods for in vitro fertilization or insemination in these patients.


Subject(s)
Infertility, Male/diagnosis , Semen/physiology , Cell Membrane/physiology , Cell Survival , Fertilization in Vitro , Humans , Insemination, Artificial , Male , Osmotic Fragility , Sperm Motility
19.
Experientia ; 46(7): 734-6, 1990 Jul 15.
Article in English | MEDLINE | ID: mdl-2164958

ABSTRACT

The dibutyryl analog of cCMP suppressed sperm amplitude of lateral head displacement and hyperactivation. Sperm motility was inhibited by dibutyryl cCMP with a shift toward less linear trajectory sperm movements. The results suggest a role of cCMP as an inhibitory signal on sperm motility patterns related to sperm capacitation.


Subject(s)
Cyclic AMP/pharmacology , Sperm Motility/drug effects , Humans , In Vitro Techniques , Male , Sperm Capacitation/drug effects , Sperm Head/physiology
20.
Theriogenology ; 33(5): 1015-9, 1990 May.
Article in English | MEDLINE | ID: mdl-16726797

ABSTRACT

The dinucleotide polyphosphate, diadenosine 5', 5'''-P(1), P(4)-tetraphosphate (Ap4A), has been identified in mammalian and non-mammalian cells as a signal molecule that initiates the process of DNA replication and cell division. The objective of this study was to determine the function of this messenger molecule in preimplantation mouse embryonic cells. Frozenthawed two-cell mouse embryos were incubated in the presence of 0, 0.1 and 1.0 mM Ap4A at 37 degrees C in moist 5% CO(2) in air mixture for 5 d. The developmental stages of the embryos in terms of hatching and implantation were evaluated. The data showed dose-dependent inhibition of blastocyst implantation; however, there were no differences observed in the number of embryos developing to the blastocyst stage. The results suggest that Ap4A neither promotes nor inhibits the development of early stage embryos except at the implantation stage, where it exerts inhibitory control.

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