To study the influence of ethnicity on the outcome of ovulation induction with clomiphene
citrate (CC) in women with polycystic ovary syndrome (PCOS).
A retrospective cohort study. In total, 420 women diagnosed with PCOS from Northern
European, Mediterranean, African, South-East Asian and South-American descent, who
started ovulation induction treatment with CC, were included. All women were treated
with CC according to standardized treatment regime. Minimal effective dose of CC,
and the prevalence of clomiphene resistance (CRA) were assessed, and we predicted
the chance to become ovulatory.
We observed differences in BMI (p=0.002), waist circumference (p=0.036), LH, insulin,
and androgen serum levels (all p<0.001) in PCOS women of different ethnicity. Compared
to women of Northern European descent, the minimal effective dose of CC in women of
other ethnic groups was not different (p>0.2). The prevalence of CRA (p=0.574) was
similar in all ethnic groups. We predicted a similar chance of ovulation (p=0.5) in
the different ethnic groups.
This is the first study aiming to link ethnicity to ovulation induction outcome in
PCOS. Although PCOS women of different ethnicity exhibit variation in phenotype expression,
it does not appear that there are differences in the prevalence of clomiphene resistant
anovulation as well as the minimal effective dose of CC. Furthermore, a prediction
model revealed no significant differences in the predicted chance to ovulate. A larger
cohort is needed to validate these findings.