The Potential Role of Growth Hormone on the Endometrium in Assisted Reproductive Technology

Growth hormone (GH) research and its clinical application for the treatment of growth disorders span more than a century. During the first half of the 20th century, clinical observations and anatomical and biochemical studies formed the basis of the understanding of the structure of GH and its various metabolic effects in animals. The following period (1958-1985), during which pituitary-derived human GH was used, generated a wealth of information on the regulation and physiological role of GH - in conjunction with insulin-like growth factors (IGFs) - and its use in children with GH deficiency (GHD). The following era (1985 to present) of molecular genetics, recombinant technology and the generation of genetically modified biological systems has expanded our understanding of the regulation and role of the GH-IGF axis. Today, recombinant human GH is used for the treatment of GHD and various conditions of non-GHD short stature and catabolic states; however, safety concerns still accompany this therapeutic approach. In the future, new therapeutics based on various components of the GH-IGF axis might be developed to further improve the treatment of such disorders. In this Review, we describe the history of GH research and clinical use with a particular focus on disorders in childhood.

A retrospective study of 3319 women was conducted to assess predictive ability of endometrial characteristics for outcomes of IVF and embryo transfer. Endometrial thickness, growth and pattern were assessed at two time points (day 3 of gonadotrophin stimulation and day of HCG administration). Endometrial patterns were classified as pattern A: triple-line pattern comprising a central hyperechoic line surrounded by two hypoechoic layers; pattern B: an intermediate isoechogenic pattern with the same reflectivity as the surrounding myometrium and poorly defined central echogenic line; and pattern C: homogenous, hyperechogenic endometrium. The endometrium of pregnant women was thinner on day 3 of stimulation, thicker on the day of HCG administration, and showed greater growth in thickness compared with non-pregnant women. Clinical pregnancy rates differed according to endometrial pattern on the day of HCG administration (55.2%, 50.9% and 37.4% for patterns A, B and C, respectively). A positive linear relationship was found between endometrial thickness on the day of HCG administration and clinical pregnancy rate. Endometrial thickness, change and pattern were independent factors affecting outcome. Receiver operator characteristic curves showed that endometrial pattern, thickness and changes were not good predictors of clinical pregnancy. Discriminant analysis indicated that 58.7% of original grouped cases were correctly classified. Although endometrium with triple-line or increased thickness may favour pregnancy, combined endometrial characteristics do not predict outcomes.

Background To evaluate the relationship between endometrial thickness on day of human chorionic gonadotrophin administration (hCG) and pregnancy outcome in a large number of consecutive in vitro fertilization and embryo transfer (IVF-ET) cycles. Methods A retrospective cohort study including all patients who had IVF-ET from January 2003–December 2005 conducted at a tertiary center. Results A total of 2464 cycles were analysed. Pregnancy rate (PR) was 35.8%. PR increased linearly (r = 0.864) from 29.4% among patients with a lining of less than or equal to 6 mm, to 44.4% among patients with a lining of greater than or equal to 17 mm. ROC showed that endometrial thickness is not a good predictor of PR, so a definite cut-off value could not be established (AUC = 0.55). Conclusion There is a positive linear relationship between the endometrial thickness measured on the day of hCG injection and PR, and is independent of other variables. Hence aiming for a thicker endometrium should be considered.