Testosterone Levels in Third Trimester in Polycystic Ovary Syndrome: Odense Child Cohort.

Background: Polycystic ovary syndrome (PCOS) is characterized by hyperandrogenism. In pregnancy, testosterone levels may be higher in women with PCOS compared with controls.

Aims: To compare total testosterone (TT), free testosterone (FT), and sex hormone-binding globulin (SHBG) levels in third-trimester pregnant women with PCOS and controls and to establish reference ranges for TT, FT, and SHBG in PCOS and controls.

Methods: The study was part of the prospective study, Odense Child Cohort. PCOS was diagnosed by questionnaires and/or patient records. Fasting blood samples were collected at gestational week 28 and plasma TT was measured by liquid chromatography-tandem mass spectrometry in women with PCOS (n = 145) and in women without PCOS (controls, n = 1341).

Results: Levels of TT (mean, 2.4 vs 2.0 nmol/L) and FT (mean, 0.005 vs 0.004 nmol/L) were higher, whereas SHBG levels (mean, 447 vs 477 nmol/L) were lower in women with PCOS vs controls (all P < 0.001). Reference intervals for TT, FT, and SHBG in women with PCOS and controls were overlapping, and partitioning of reference intervals was an ambiguous decision. In multiple regression analyses, TT and FT levels were positively associated with PCOS status and BMI and inversely associated with age and parity. Offspring sex did not predict maternal TT and FT.

Conclusions: TT and FT levels were higher in third-trimester pregnant women with PCOS compared with controls. Separate reference interval for FT in women with PCOS should be considered.