Objectives: To investigate pregnancy outcomes after
frozen-thawed embryo transfer (FET) according to polycystic ovary
syndrome (PCOS) phenotypes. Design: Retrospective study. Setting:
University-based centre for reproductive medicine. Participants: 8903
patients who underwent FET between January 2017 and October 2019.
Methods: All patients were divided into PCOS and control groups, with
the former categorised into four phenotype groups (PCOS phenotypes A, B,
C, D) based on Rotterdam criteria. All patient data were retrospectively
collected and evaluated. Main outcome measures: Pregnancy outcomes after
FET consisted of biochemical, clinical and ectopic pregnancies,
abortion, premature delivery and live birth. Results: Women with PCOS
phenotype A experienced an increased incidence of biochemical pregnancy,
clinical pregnancy and premature delivery compared to those with PCOS
phenotype D and in the control group (P < 0.001, P = 0.005, P
= 0.006, respectively), while incidences of ectopic pregnancy and live
birth were comparable between all groups (P > 0.05). We
found significantly higher abortion (P = 0.010) and lower ongoing
pregnancy (P = 0.023) rates for women with PCOS phenotypes A and D
compared to those in the control group. After adjusting for potential
confounders, PCOS phenotypes A and D (vs. control) were associated with
an elevated risk of abortion (adjusted odds ratio [OR], 1.476, 95%
confidence interval [CI], 1.077–2.024, P = 0.016; adjusted OR,
1.348, 95% CI, 1.080–1.682, P = 0.008, respectively). Conclusions: For
the first time, our study demonstrates that women with PCOS phenotypes A
and D show an increased risk of abortion after FET.