Hormonal Replacement Therapy in Premenopausal Women With Hypogonadism: An Analysis of Prescriber Practices

Introduction: Estrogen replacement therapy in premenopausal women with hypogonadism is important for reducing risk of osteoporosis, cardiovascular disease, and urogenital atrophy. Numerous formulations of estrogen are available and there is limited evidence to guide management. We conducted a preliminary retrospective study to determine prescribing practices of hormonal replacement therapy (HRT) in premenopausal women with hypogonadism and frequency of DEXA scan screening. Methods: Using ICD 10 and billing codes, females ages 18-51 with a diagnosis of hypogonadism were identified. Patients with a diagnosis of prolactinoma, breast or endometrial cancer, and significant thrombotic disease as well as patients without clinical data were excluded. Information regarding etiology of hypogonadism, age of diagnosis, type/dose of estrogen and progesterone prescribed, prescriber specialty [obstetrics and gynecology (OB/GYN), endocrinology (ENDO), primary care (PCP), or other], and DEXA results was recorded. Prescriptions for estrogen and progesterone were compared in women with primary vs secondary hypogonadism and among specialties. For bone density, we analyzed the frequency of DEXA scan ordering. Statistical analysis was performed using Fisher’s Exact Test. Results: Out of 1,306 patients identified, 150 met criteria for analysis. 99 (66%) had primary hypogonadism, 47 (31%) had secondary hypogonadism, and 4 (3%) had mixed or unknown type. OB/GYN was the most common prescriber (n=88, 59%) followed by ENDO (n=39, 26%) and PCP/other (n=23, 15%). For all patients, type of estrogen prescribed differed by specialty (p=0.041) with ENDO most commonly prescribing transdermal estradiol (47%), OB/GYN either transdermal estradiol (30%) or oral ethinyl estradiol (30%), and PCP/other oral estradiol (45%). Patients with primary, but not secondary hypogonadism, were prescribed more transdermal estradiol by ENDO as compared to OB/GYN (68% vs 27%, p=0.039). In patients with secondary hypogonadism on oral ethinyl estradiol, mean daily dose (mcg) differed among providers ((ENDO 27 ± 6, OB/GYN 35 ± 8, PCP/other 10 ± 0, p=0.04). There was no difference in dosing of other types of estrogen, prescribing practices for progesterone, or frequency of DEXA scans among providers. DEXA scans were performed at least once in 59 (39%) and more than once in 20 (13%) patients. Conclusions: Overall, premenopausal women with hypogonadism seeing ENDO as compared to other providers were more frequently prescribed transdermal estradiol as compared to oral estradiol and/or other types of estrogen. Only dosages of oral ethinyl estradiol differed by provider. Despite an increased risk of osteoporosis, a minority of patients underwent DEXA scans. This study highlights heterogeneity in prescribing practices and underscores the need for further research to guide management of premenopausal women with hypogonadism.