Table 3. Studies investigating the relationship between thyroid disorders and PE in men.

Study	Year	Definition of PE	Disorder	PE prevalence	Results
Corona et al [45]	2004	PE was defined as ejaculation within 1 minute of vaginal intromission (as reported by the patient).	Hyperthyroidism	TSH ↓ 0.2 mU/L 57.1% TSH ↑ 0.2 mU/L 26.5%	TSH <0.2 mU/L and ED had higher rates of PE. Hyperthyroidism is associated with PE independent of ED.
Carani et al [73]	2005	DMS-IV	Hypothyroidism, hyperthyroidism	Hypothyroidism 7.1% Hyperthyroidism 50%	The prevalence of PE decreased from 50% to 15% after 2–4 months of treatment.
Waldinger et al [78]	2005	IELT ≤1 minute	Hyperthyroidism	-	There is no relationship between LPE and hypo- or hyperthyroidism.
Cihan et al [75]	2009	DMS-IV	Hyperthyroidism	72.0%	Correlation between IELT and TSH levels. Increase the IELT and decrease in the incidence of PE to 25% after treatment.
Cihan et al [76]	2009	Animal study	Hyperthyroidism	-	Hyperthyroid rat ejaculation time is shorter than control and returns to normal after treatment.
Corona et al [30]	2011	PE was defined as ejaculation within 1 minute of vaginal intromission (as reported by the patient).	Hyperthyroidism	42.40%	TSH level affected the ejaculation time independent of age, testosterone, or prolactin level, and the increase in TSH caused an increase in IELT levels.
Oztürk et al [77]	2012	Unspecified	Hyperthyroidism	-	Hyperprolactinemia was detected in 19 participants (17.8%) and TSH was below normal in 9 patients (8.4%) in the PE group. Mean serum prolactin and free T4 concentrations were found to be significantly higher in the PE group.
Canat et al [32]	2017	PEDT	Hyperthyroidism	-	TSH levels lower in PE men.

PE: premature ejaculation, TSH: thyroid stimulating hormone, ED: erectile dysfunction, DMS-IV: Diagnostic and Statistical Manual of Mental Disorders-IV, IELT: intravaginal ejaculatory delay time, LPE: lifetime pemature ejaculation, PEDT: premature ejaculation diagnostic tool, -: not available.