Recurrent miscarriage and hCG supplementation: a review and metaanalysis

Long-acting microspheres of Human Chorionic Gonadotropin hormone: In-vitro and in-vivo evaluation

Human Chorionic Gonadotropin (hCG) hormone is used to cause ovulation, treat infertility in women, and increase sperm count in men. Conventional hCG solution formulations require multiple administration of hCG per week and cause patient noncompliance. The long-acting PLGA depot microspheres (MS) approach with hCG can improve patient compliance, increase the efficacy of hCG with a lower total dose and improve quality of life. Therefore, hCG was encapsulated by a modified double emulsion solvent evaporation technique within PLGA MS by high-speed homogenizer and industrially scalable in-line homogenizer, respectively. MS was characterized for particle size, encapsulation efficiency (EE), surface morphology, and in-vitro release. The spherical, dense, non-porous microspheres were obtained with a size of 58.88 ± 0.18 µm. Microspheres showed high EE (77.4% ± 5.9%) with low initial burst release (12.82% ± 2.07%). Circular Dichroism and SDS-PAGE analysis indicated good stability and structural integrity of hCG in the microspheres. Its bioactivity was proven further by a bioassay study in immature Wistar rats. Pharmacokinetic analysis showed that the hCG PLGA MS maintained serum hCG concentration up to 13 days compared to multiple injections of a marketed conventional parenteral injectable formulation of hCG. Thus, it can be ascertained that the hCG PLGA MS may have great potential for clinical use in long-term therapy.

Recurrent pregnancy loss - beyond evidence based medicine

Patients with five or more unexplained recurrent pregnancy losses (RPL) have a poor prognosis for a subsequent delivery compared to patients with two to three RPL. Treatment guidelines are needed to address this select group of patients.

Extragonadal actions of chorionic gonadotropin

The primary embryonic signal in primates is chorionic gonadotropin (CG, designated hCG in humans), that is classically associated with corpus luteum rescue and progesterone production. However, research over the past decade has revealed the presence of the hCG receptor in a variety of extragonadal tissues. Additionally, discoveries of the multiple variants of hCG, namely, native hCG, hyperglycosylated hCG (hyp-hCG) and the β- subunit of the hyperglycosylated hCG (hCG-free β) has established a role for extragonadal actions of hCG. For the initiation and maintenance of pregnancy, hCG mediates multiple placental, uterine and fetal functions. Some of these include development of syncytiotrophoblast cells, mitotic growth and differentiation of the endometrium, localized suppression of the maternal immune system, modulation of uterine morphology and gene expression and coordination of intricate signal transduction between the endometrium. Recurrent pregnancy loss, pre-eclampsia and endometriosis are associated with altered responses of hCG, all of which have a detrimental effect on pregnancy. A role for hyp-hCG in mediating the development of both trophoblastic and non-trophoblastic tumors has also been suggested. Other significant non-gonadal applications of hCG include predicting preeclampsia, determining the risk of Down's syndrome and gestational trophoblastic disease, along with relaxing myometrial contractility and preventing recurrent miscarriages. Presence of hCG free-β in serum of cancer patients enables its usage as a diagnostic tumor marker. Thus, the extragonadal functions of hCG encompasses a wide spectrum of applications and is an open area for continued investigation.