John Buster - Research

Research

Buster's forty years of research and clinical practice in reproductive medicine include numerous published studies in steroid physiology, pre-implantation embryology, pregnancy loss, and menopausal hormone replacement therapy.

Buster is a leading researcher in female sexual dysfunction (FSD), a continuum of psychosexual disorders centered on loss of sexual desire with interrelated problems of arousal, orgasm, and sexual pain. Buster has recently outlined awareness and treatment for sexual dysfunction for both the physician and post-menopausal woman.

Buster authored "Sex and the 50-Something Woman: Strategies for Restoring Satisfaction" in the professional journal of Contemporary Obstetrics and Gynecology. The intent was to explain the various causes of what is called female sexual dysfunction (FSD) and the simple interventions obstetrician/gynecologists and primary care physicians can recommend. The article attracted national interest with stories appearing in local media, creating greater awareness for the treatment and open dialogue for woman.

One of Buster's earliest research studies focused on steroid hormone radioimmunoassay (RIA). He reported an RIA for the androgen prohormone, dehydroepiandrosterone sulfate (DHEA-S), the direct measurement of which was shown to be possible in un-extracted serum. Refined versions of his methodology are used today in the diagnosis and management of androgen excess disorders in women.

Buster's development of a simple nonchromatographic RIA to measure un-conjugated estriol in pregnancy serum led to more refined versions of this method that are used today in the early diagnosis of chromosomal abnormalities in mid-trimester pregnant women. He also described for the first time the simultaneous progression of multiple androgens, progestins, and estrogens concentrations in maternal blood throughout all three trimesters of pregnancy and into the onset of labor.

In the early 1980s, over a period of 4 years, at the University of California at Los Angeles School of Medicine, Buster and his team developed a revolutionary technique based on in-vivo fertilization and uterine lavage – a method adapted from the commercialization of bovine embryo transfer in the cattle industry – as a means to transfer human blastocysts from fertile woman donors to ovulating or agonadal infertile recipient women (6) Specifically, the group developed a simple office procedure in which blastocyst, which had been deliberately created from in vivo fertilization in the donor’s body using infertile recipient’s husband sperm, were transferred to produce pregnancy in an infertile recipient woman. In February 1984, the historical first live birth, followed 3 months later by a second live birth, resulted from these techniques and was reported by Buster and his team.

A University of California at Los Angeles team, under Buster's direction, contemporaneous with a group from Northwestern University, published findings on the first case series of ectopic pregnancies (outside the uterus) treated successfully with methotrexate, a cancer chemotherapy agent. This approach became widely accepted in the 1990s and continues to save thousands of women from major surgery customarily associated with ectopic pregnancy, a dangerous and potentially fatal complication of human reproduction.

More recently, Buster helped develop a testosterone delivery system for women researched by Procter & Gamble. It is now marketed in Europe under the brand name Intrinsa. The product – a trans-dermal patch – is designed to deliver chemically identical testosterone directly into the micro vascular circulation-much like an artificial endocrine organ. Buster was lead investigator in a major study that demonstrated the effectiveness of this patch to treat decreased sexual desire in oophorectomised, postmenopausal women (13). These patches are in use outside of the United States to treat hypoactive sexual desire in women who are deficient of androgens.

Most recently, Buster served as lead investigator in another major study demonstrating the effectiveness of an estradiol mist, which has pharmacology similar to those of a trans-dermal estrogen patches (14). Sold in the United States by TherRx Corporation under the name Evamist, the spray offers additional margins of safety and convenience over traditional oral and patch-administered estrogen's. Evamist won FDA approval in 2007. Buster's Phase III Study for Evamist was published in the Journal, Obstetrics & Gynecology, in June 2008.