Meeting the demand for fertility services: the present and future of reproductive endocrinology and infertility in the United States

The field of reproductive endocrinology and infertility (REI) is at a crossroads; there is a mismatch between demand for reproductive endocrinology, infertility and assisted reproductive technology (ART) services, and availability of care. This document's focus is to provide data justifying the critical need for increased provision of fertility services in the United States now and into the future, offer approaches to rectify the developing physician shortage problem, and suggest a framework for the discussion on how to meet that increase in demand. The Society of REI recommend the following: 1. Our field should aggressively explore and implement courses of action to increase the number of qualified, highly trained REI physicians trained annually. We recommend efforts to increase the number of REI fellowships and the size complement of existing fellowships be prioritized where possible. These courses of action include: a. Increase the number of REI fellowship training programs. b. Increase the number of fellows trained at current REI fellowship programs. c. The pros and cons of a 2-year focused clinical fellowship track for fellows interested primarily in ART practice were extensively explored. We do not recommend shortening the REI fellowship to 2 years at this time, because efforts should be focused on increasing the number of fellowship training slots (1a and b). 2. It is recommended that the field aggressively implements courses of action to increase the number of and appropriate usage of non-REI providers to increase clinical efficiency under appropriate board-certified REI physician supervision. 3. Automating processes through technologic improvements can free providers at all levels to practice at the top of their license.

Hypothalamic obesity

Hypothalamic obesity represents a rare diagnosis applicable to only a small subset of obese patients. It is important to identify, diagnose, and treat these patients. This article reviews the physiology of the hypothalamus, focusing on its role in regulation of hunger, feeding, and metabolism. The causes of hypothalamic obesity are discussed including genetic, anatomic, and iatrogenic etiologies. The complex hormonal environment leading to obesity is explored for each etiology and treatment strategies are discussed. Reproductive consequences are also reviewed.

Luteal phase dynamics of follicle-stimulating and luteinizing hormones in obese and normal weight women

OBJECTIVES

Female obesity is a state of relative hypogonadotrophic hypogonadism. The aim of this study is to examine gonadotrophin secretion and response to gonadotrophin-releasing hormone (GnRH) in the luteal phase of the menstrual cycle and to investigate the pharmacodynamics and pharmacokinetics of endogenous and exogenous luteinizing hormone (LH) in obese women.

DESIGN

Participants underwent a luteal phase frequent blood sampling study. Endogenous LH pulsatility was observed, gonadotrophin-releasing hormone (GnRH) was given in two weight-based doses, and GnRH antagonist was administered followed by recombinant LH.

PATIENTS

Regularly menstruating obese (n = 10) and normal weight (n = 10) women.

MEASUREMENTS

Endogenous hypothalamic-pituitary function (as measured by LH pulsatility), pituitary sensitivity (GnRH-induced LH secretion), pharmacodynamics of endogenous LH and pharmacokinetics of exogenous LH were compared between the obese and normal weight groups.

RESULTS

There were no statistically significant differences in endogenous LH pulsatility or pituitary responses to two weight-based doses of GnRH between the obese and normal weight women. There were no differences in the pharmacodynamics of endogenous LH or the pharmacokinetics of exogenous LH between the groups. FSH dynamics did not differ between the groups throughout the study.

CONCLUSIONS

The relative hypogonadotrophic hypogonadism of obesity cannot be explained by differences in LH and FSH luteal phase dynamics or differences in endogenous LH pharmacodynamics or exogenous LH pharmacokinetics.

Evidence of GnRH antagonist escape in obese women

CONTEXT

Assisted reproductive technology (ART) cycle cancelation rates are increased among overweight and obese women; however, the reasons for this are not completely clear. Premature luteinization due to inadequate endogenous gonadotropin suppression is a possibility for this higher risk of cancellation.

OBJECTIVE

The objective of the study was to investigate the impact of female obesity on the pharmacokinetics of cetrorelix (GnRH antagonist).

DESIGN

This was an interventional study.

SETTING

The study was conducted at a university clinical and translational research center.

PARTICIPANTS

Regularly menstruating obese (n = 10) and normal-weight (n = 10) women participated in the study.

INTERVENTIONS

A frequent blood sampling study was performed after a GnRH antagonist was administered, followed by recombinant LH.

MAIN OUTCOMES MEASURED

Pharmacokinetics of cetrorelix in obese vs normal weight women were measured.

RESULTS

Five of the obese women (50%) and none of the normal-weight women had a rebound of LH (defined as >50% increase in LH level from nadir) over the 14-hour postdose observation period. The obese group had a significantly decreased distributional half-life of cetrorelix compared with the normal-weight group (8.1 ± 1.6 vs 12.7 ± 6.2 hours, P = .02). The obese group exhibited increased clearance of cetrorelix compared with the normal-weight group (25.8 ± 6.8 vs 20.1 ± 8.3 L/h, P = .058).

CONCLUSIONS

The altered pharmacokinetics of cetrorelix in obese women may lead to premature ovulation during ART, and this could be one of the mechanisms that results in increased cycle cancelation in this group of women. In accordance with the higher gonadotropin requirements for obese women undergoing ART, weight-based dosing of GnRH antagonists may be required.

Pregnancy in a woman with premature ovarian insufficiency associated with blepharophimosis, ptosis, epicanthus inversus syndrome type I. A case report

BACKGROUND

Blepharophimosis, ptosis, epicanthus inversus syndrome (BPES) type I is a rare disorder that causes a recognizable pattern of eye abnormalities and is associated with premature ovarian insufficiency. There is no data to guide the treatment of these patients when presenting with infertility.

CASE

A 30-year-old, nulligravid woman with premature ovarian insufficiency associated with BPES type I presented to care secondary to a desire to conceive. Ovarian stimulation with gonadotropins was performed, and the patient conceived and delivered viable twins.

CONCLUSION

It is not known whether premature ovarian insufficiency associated with BPES type I follows the same clinical course as idiopathic premature ovarian insufficiency. In patients with BPES type I who present with infertility, ovarian stimulation with gonadotropins may be a reasonable therapeutic option.

Can we live longer by eating less? A review of caloric restriction and longevity

Caloric restriction, decreasing caloric intake by 20-30%, was first shown to extend life in rats nearly 80 years ago. Since that time, limiting food intake for longevity has been investigated in species from yeast to humans. In yeast and lower animals, caloric restriction has repeatedly been demonstrated to lengthen the life span. Studies of caloric restriction in non-human primates and in humans are ongoing and initial results suggest prolongation of life as well as prevention of age-related disease. There is also data in rodents suggesting that short term caloric restriction has beneficial effects on fertility. Although caloric restriction has many positive effects on health and longevity, quality of life on a restricted diet as well as the ability to maintain that diet long term are concerns that must be considered in humans.

Beta-thymosin, a modulator of the actin cytoskeleton is increased in regenerating retinal ganglion cells

Beta-thymosins are actin monomer-binding polypeptides that are expressed in a neuronal growth-specific manner during embryonic development. Here, we show that regenerating retinal ganglion cells and non-neuronal cells of the optic nerve transiently activate beta-thymosin transcription after optic nerve lesion in the zebrafish. In retinal cell cultures, beta-thymosin is found at highest concentration in growth cones, branching points and varicosities of neurite-extending retinal ganglion cells. These places often exhibit reduced phalloidin staining, indicating that beta-thymosin promotes the disassembly of actin filaments. Beta-thymosin distribution within neurons in culture is distinct from actin, tubulin and the actin-severing protein gelsolin. Ectopic expression of beta-thymosin in a central nervous system (CNS) catecholaminergic cell line leads to alterations in the shape of the cell bodies and neurites. Beta-thymosin-positive cells spread more fully and exhibit an excessive degree of branching. We partially cloned two other actin-binding proteins, profilin and gelsolin, and analysed their expression patterns. Profilin is constitutively expressed in virtually all cells. Gelsolin, like beta-thymosin, is selectively increased in regenerating retinal ganglion cells. During development, however, gelsolin mRNA is not detected in the nervous system. These findings indicate that distinct mechanisms control the actin cytoskeleton in embryonic and regenerating neurons, and that beta-thymosin may be a major regulator of actin dynamics in the zebrafish CNS.

beta-thymosin is required for axonal tract formation in developing zebrafish brain

beta-Thymosins are polypeptides that bind monomeric actin and thereby function as actin buffers in many cells. We show that during zebrafish development, β-thymosin expression is tightly correlated with neuronal growth and differentiation. It is transiently expressed in a subset of axon-extending neurons, essentially primary neurons that extend long axons, glia and muscle. Non-neuronal expression in the brain is restricted to a subset of glia surrounding newly forming axonal tracts. Skeletal muscle cells in somites, jaw and fin express beta-thymosin during differentiation, coinciding with the time of innervation. Injection of beta-thymosin antisense RNA into zebrafish embryos results in brain defects and impairment of the development of beta-thymosin-associated axon tracts. Furthermore, irregularities in somite formation can be seen in a subset of embryos. Compared to wild-type, antisense-injected embryos show slightly weaker and more diffuse engrailed staining at the midbrain-hindbrain boundary and a strong reduction of Isl-1 labeling in Rohon Beard and trigeminal neurons. The decreased expression is not based on a loss of neurons indicating that beta-thymosin may be involved in the maintenance of the expression of molecules necessary for neuronal differentiation. Taken together, our results strongly indicate that beta-thymosin is an important regulator of development.

zfNLRR, a novel leucine-rich repeat protein is preferentially expressed during regeneration in zebrafish

zfNLRR is a novel transmembrane protein that is most prominently expressed during regeneration of the zebrafish central nervous system. Retinal ganglion cells and descending spinal cord neurons strongly increase zfNLRR mRNA levels after axotomy in the adult. In contrast, during development expression is hardly detectable and is restricted to a few sensory systems. In the adult brain, zfNLRR mRNA is found at low levels in several motor and premotor systems. Sequence analysis reveals that zfNLRR contains in its extracellular region 12 leucine-rich repeats, 1 immunoglobulin-like domain and 1 fibronectin type III-like domain. The same protein binding motifs were identified in transmembrane proteins from frog, mouse, and human. Together, they constitute a novel family of vertebrate neuronal leucine-rich repeat proteins. Three distinct isoforms are identified so far. On the basis of its structural features and expression pattern, we propose that zfNLRR functions as a neuronal-specific adhesion molecule or soluble ligand binding receptor, primarily during restoration of the nervous system after injury.

Target contact regulates GAP-43 and alpha-tubulin mRNA levels in regenerating retinal ganglion cells

Axotomy of vertebrate neurons leads to the transient upregulation of GAP-43 and alpha-tubulin. In adult zebrafish retina, mRNA levels of both genes were increased in retinal ganglion cells after optic nerve lesion following a similar time course. At 5 days after crush, the mRNA level of GAP-43 was increased nearly 20 times, whereas a 6-fold increase was observed for alpha-tubulin. Subsequently, upon target reinnervation, mRNA levels of both genes were downregulated and were 2-fold higher than normal at 25 days after crush. Stretching the optic nerve that results in diffuse axonal lesions led to the expression of both genes in identical subsets of retinal ganglion cells. When regeneration was prevented by removing a piece of the optic nerve, mRNA levels remained elevated. Disruption of axonal transport by colchicine and vinblastine led to the induction of both genes in normal retina. Blocking electrical activity with tetrodotoxin had no effect. This indicates that retrogradely transported signals induced by target contact regulate GAP-43 and alpha-tubulin transcription. Furthermore, the joint regulation of GAP-43 and alpha-tubulin mRNA levels after different kinds of lesion suggests that a common pathway underlies the regulation of neuronal GAP-43 and alpha-tubulin gene expression. In contrast, distinct mechanisms may control the extent and maintenance of increased mRNA levels of these genes.