Endometrial Peristalsis, Endometrial Waves, Frozen Embryo Transfer (FET), Hormone Replacement Therapy (HRT), Infertility, Uterine Contraction, Uterine Peristalsis
Conditions
Keywords
endometrial peristalsis, uterine contractions, endometrial waves, frozen embryo transfer, artificial cycles
Brief summary
Endometrial peristalsis may influence embryo implantation and pregnancy outcomes, but its role during hormone replacement therapy (HRT)-prepared frozen embryo transfer (FET) cycles remains unclear. This prospective observational study will assess endometrial peristalsis at predefined time points during HRT-prepared FET cycles using transvaginal ultrasonography and evaluate its association with pregnancy outcomes. The study aims to clarify the clinical significance of endometrial peristalsis in HRT-prepared FET cycles and to provide evidence supporting endometrial assessment in assisted reproductive technology.
Detailed description
Frozen embryo transfer (FET) has become an integral component of assisted reproductive technology (ART), and successful implantation depends on adequate endometrial receptivity. Different endometrial preparation protocols, including natural cycles and hormone replacement therapy (HRT) cycles, create distinct hormonal environments that may influence endometrial physiology. Among these protocols, HRT is the most widely used approach because it is applicable to a broad range of patients and offers greater flexibility in treatment scheduling. Endometrial peristalsis, characterized by rhythmic contractions of the uterine junctional zone, is thought to play an important role in embryo transport and implantation. Previous studies have suggested that the frequency and direction of endometrial peristalsis are influenced by ovarian steroid hormones and may be associated with implantation and pregnancy outcomes. However, most available evidence has focused on natural menstrual cycles, while data regarding endometrial peristalsis during HRT-prepared FET cycles remain limited and inconsistent. The temporal changes in endometrial peristalsis throughout HRT endometrial preparation and their relationship with reproductive outcomes have not been fully elucidated. This prospective observational study is designed to characterize endometrial peristalsis during HRT-prepared FET cycles using transvaginal ultrasonography and to evaluate the association between endometrial peristalsis and pregnancy outcomes. Endometrial peristalsis will be assessed at predefined time points during endometrial preparation, and pregnancy outcomes will be compared according to the observed peristaltic patterns. The results of this study are expected to improve understanding of endometrial physiology during HRT-prepared FET cycles and provide evidence on the clinical significance of endometrial peristalsis for reproductive outcomes.
Interventions
Time point for measurement of endometrial peristalsis will be assessed at three specific time points: * On the second day to the fourth day of the menstrual cycle in the FET cycles. * The day of progesterone initiation (before progesterone exposure) * On the day of embryo transfer, immediately prior to the procedure Hormone measurements: serum levels of estradiol (E2) and progesterone (P4) will be assessed three times, on the same days as the endometrial peristalsis measurements, using electrochemiluminescence immunoassays. (Elecsys® Estradiol III and Elecsys® Progesterone III, Cobas® e 411, Roche Diagnostics, Germany): * On the second day to the fourth day of the menstrual cycle in the FET cycles * The day of progesterone initiation * On the transfer day prior to the procedure.
Sponsors
Mỹ Đức Hospital
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
FEMALE
Age
18 Years to 42 Years
Healthy volunteers
No
Inclusion criteria
* Women aged 18 - 42 years old * Scheduled for frozen embryo transfer cycles using hormone replacement therapy protocol * Transferred no more than two cleavage embryos or one good-quality blastocyst or no more than two poor-quality blastocysts * Provision of written informed consent to participate
Exclusion criteria
* Having an allergy and contraindications for exogenous hormone administration (e.g., breast cancer, thromboembolic disease) * Cycles with preimplantation genetic testing, oocyte donation, or in vitro maturation * Having untreated uterine or adnexal abnormalities (e.g., intrauterine adhesions, unicornuate/ bicornuate/ arcuate uterus, endometrial polyp, large leiomyoma ≥5 cm in diameter, hydrosalpinx, endometrial hyperplasia) * Use of uterine relaxants or intralipid infusion during the embryo transfer process * Use of a GnRH-agonist for downregulation within one month
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| The correlation between endometrial peristalsis at different time points and live birth rates | Up to delivery | The correlation between endometrial peristalsis at different time points and live birth rates |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| The frequency of endometrial peristalsis at different time points | • On the second day to the fourth day of the menstrual cycle in the FET cycles. • The day of progesterone initiation (before progesterone exposure) • On the day of embryo transfer, immediately prior to the procedure | The frequency of endometrial peristalsis at different time points |
| The correlation between endometrial peristalsis at different time points | • On the second day to the fourth day of the menstrual cycle in the FET cycles. • The day of progesterone initiation (before progesterone exposure) • On the day of embryo transfer, immediately prior to the procedure | The correlation between endometrial peristalsis at different time points |
| Direction of peristalsis | • On the second day to the fourth day of the menstrual cycle in the FET cycles • The day of progesterone initiation (before progesterone exposure) • On the day of embryo transfer, immediately prior to the procedure | Direction of peristalsis is categorized as cervix-to-fundus, fundus-to-cervix, indeterminate, or absent (no contractions observed) |
| The association between endometrial peristalsis at different time points and pregnancy rates | Up to delivery | The association between endometrial peristalsis at different time points and pregnancy rates |
| Live birth rates after the one embryo transfer | At delivery | Live birth was defined as the complete expulsion or extraction from a woman of a product of fertilization, after 22 completed weeks of gestational age; which, after such separation, breathes or shows any other evidence of life, such as heartbeat, umbilical cord pulsation, or definite movement of voluntary muscles, irrespective of whether the umbilical cord has been cut or the placenta is attached. A birth weight of 500 grams or more can be used if gestational age is unknown. Live births refer to the individual newborn; for example, a twin delivery represents two live births |
| Positive pregnancy test | 10-14 days after embryo transfer | Defined as serum human chorionic gonadotropin level ≥ 25 mIU/mL |
| Clinical pregnancy | 4-6 weeks after embryo transfer | A pregnancy diagnosed by ultrasonographic visualization of one or more gestational sacs or definitive clinical signs of pregnancy. In addition to intra-uterine pregnancy, it includes a clinically documented ectopic pregnancy |
| Ongoing pregnancy | 12 weeks of gestation or beyond | A pregnancy diagnosed by ultrasonographic or clinical documentation of at least one fetus with a discernible heartbeat at 12 weeks gestation or beyond |
| Implantation rate | At 4-6 weeks after embryo transfer | The number of gestational sacs observed divided by the number of embryos transferred (usually expressed as a percentage) |
| Ectopic pregnancy | Up to 12 weeks after embryo transfer | A pregnancy outside the uterine cavity, diagnosed by ultrasound, surgical visualization, or histopathology |
| Miscarriage | Up to 22 weeks of gestation | Spontaneous loss of a clinical pregnancy before 22 completed weeks of gestational age, in which the embryo(s) or fetus(es) is/are nonviable and is/are not spontaneously absorbed or expelled from the uterus |
| Multiple gestations | At delivery | A pregnancy with more than one embryo or fetus |
| Multiple birth | At delivery] | The complete expulsion or extraction from a woman of more than one fetus, after 22 completed weeks of gestational age, irrespective of whether it is a live birth or stillbirth. Births refer to the individual newborn; for example, a twin delivery represents two births |
| Mode of delivery | At delivery | Vaginal delivery, C-section (elective, suspected fetal distress, non-progressive labor) |
| Birth weight | At delivery | Weight of the newborn measured right after delivery |
| Gestational age at birth | At delivery | Calculated by gestational age of all live births |
| Preterm birth | At delivery | Defined as delivery at \<28, \<32, \<37 completed weeks. A birth that takes place after 22 weeks and before 37 completed weeks of gestational age |
| Gestational diabetes mellitus | At 24-28 weeks of gestation | A 75-g OGTT, with plasma glucose measurement when the patient is fasting and at 1 and 2 h, at 24-28 weeks of gestation in women not previously diagnosed with diabetes |
| Hypertensive disorders of pregnancy | Up to delivery | Hypertensive disorders of pregnancy: Pregnancy-induced hypertension, pre-eclampsia (early and late), eclampsia, and HELLP syndrome are defined in the American College of Obstetricians and Gynecologists (ACOG) 2020 |
| Stillbirth | Up to delivery | The death of a fetus before the complete expulsion or extraction from its mother after 28 completed weeks of gestational age. The death is determined by the fact that, after such separation, the fetus does not breathe or show any other evidence of life, such as heartbeat, umbilical cord pulsation, or definite movement of voluntary muscles. Note: It includes deaths occurring during labor |
| Very low birth weight | Up to delivery | Birth weight less than 1.500 g |
| Low birth weight | Up to delivery | Birth weight less than 2.500 g |
| High birth weight | Up to delivery | Implies growth beyond an absolute birth weight, historically 4.000 g or 4.500 g, regardless of the gestational age |
| Very high birth weight | Up to delivery] | Birth weight over 4.500 g for women with diabetes, and a threshold of 5000 g for women without diabetes |
| Major congenital abnormalities | Up to delivery | Structural, functional, and genetic anomalies that occur during pregnancy, and are identified antenatally, at birth, or later in life, and require surgical repair of a defect, or are visually evident, or life-threatening, or cause death. Any congenital anomaly will be included as follows definition of congenital abnormalities in Surveillance of Congenital Anomalies by Division of Birth Defects and Developmental Disabilities, NCBDDD, Centers for Disease Control and Prevention (2020) |
| NICU admission | Up to delivery | The admission of the newborn to the NICU |
| Neonatal mortality | Up to delivery | Death of a live-born baby within 28 days of birth. This can be divided into early neonatal mortality, if death occurs in the first seven days after birth, and late neonatal if death occurs between 8 and 28 days after delivery |
Countries
Vietnam
Contacts
CONTACTNhi NL Ho, MD
CONTACTVu NA Ho, MD, PhD
PRINCIPAL_INVESTIGATORLan N Vuong, MD, PhD
University of Medicine and Pharmacy at Ho Chi Minh City
Outcome results
None listed