Administration of Human Chorionic Gonadotrophin Before Secretory Transformation of Frozen-thawed Embryo Transfer Cycles

• Status: Recruiting
• Trial end date: 2022-05-01
• Target enrollment: 0
• Participant gender: Female

Summary

To investigate the role of parenteral hCG used for the transfer of cryopreserved- thawed embryos with HRT cycles in the outcome of artificially prepared FET cycles. Frozen-thawed embryo transfer (FET) cycles has increased recently contributing to about 30% of ART cycles,which improved pregnancy outcome from each oocyte retrieval.

Despite the extensive research in all areas of reproductive medicine and breakthroughs in ART to improve cycle outcome, the efficacy of embryo implantation is relatively low and continues to be the rate limiting factor. Successful embryo implantation is complicated process that requires synchrony between good-quality embryos and receptive endometrium. It is associated with the liberation and presence of various mediators secreted from both the developing embryo and the endometrium such as cyclic adenosine monophosphate (cAMP), relaxin, gonadotropin, prostaglandin E2 (PGE2), and glycoprotein. The achievement of optimal endometrial preparation in FET cycles is important not only for proper implantation but also for pregnancy outcome. However, no consensus on the optimal endometrial preparation protocol and various protocols are used in FET: modified natural, stimulated and artificial cycles, with the latter is the most commonly used. In artificial cycle, the endometrium is prepared by administration of exogenous oestrogen followed by progesterone to induce secretory transformation before embryo transfer (ET). Both hormones are essential for adequate endometrial preparation for implantation. Another key molecule that principally controls implantation is the human chorionic gonadotropin (hCG),which is one of the initial embryonic signals and the major embryoendometrial relationship regulator. It is expressed by blastocyst before the implantation, then increasingly produced the syncytiotrophoblast after implantation. The LH and hCG receptors are present in the human endometrium, via these receptors, local hCG has several paracrine effects at implantation site that modulate endometrial receptivity and finally lead to a stable implantation. It has been found to prolong the window of receptivity and enhance endometrial

angiogenesis through down regulation of insulin- like growth factor- binding protein 1 (IGFBP-1) and increasing vascular endothelial growth factor (VEGF), respectively. It also interferes with the biosynthesis of leukemia inhibitory factor and macrophage colony stimulating factor (LIF and M-CSF) both are involved in the embryo-maternal cross-talk and modulate trophoblast differentiation. In addition, hCG has been shown to have autocrine effects on the trophoblasts themselves, leading to increased differentiation and invasive potential, "hCG could well be a key regulator, triggering whether or not the embryo will implant". Although several studies investigated the role of intrauterine administration of hCG before embryo transfer on IVF outcome, this approach is not recommended yet and many reports are conflicting. On the other hand, because parenteral hCG is not usually used for the transfer of cryopreserved- thawed embryos with HRT cycles as ovulation is usually suppressed, there are few data about the benefit of hCG administration in the outcome of artificially prepared FET cycles.

• Phase: Phase 1
• Accepts Healthy Volunteers?: No

Details

• Lead Sponsor: Alexandria University
• Treatments: Chorionic Gonadotropin

Criteria

Inclusion Criteria:

• Patient age ≤ 38 years.

• Normal 3D transvaginal ultrasound.

• At least two good quality embryos cryopreserved by vitrification.

• No GnRH agonists administration before FET cycle.

Exclusion Criteria

• Endometriosis.

• Uterine anomalies.

• Evidence of hydrosalpinx by hystrosalpingography or ultrasound.

• Evidence of immune disease, hematological or hormonal disorder.