South Asian women with polycystic ovary syndrome exhibit greater sensitivity to gonadotropin stimulation with reduced fertilization and ongoing pregnancy rates than their Caucasian counterparts.
Polycystic ovary syndrome (PCOS) is a heterogeneous syndrome. In vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) is required for PCOS cases that are refractory to standard ovulation induction or have co-existing infertility factors in women with PCOS and Tubal factor subfertility.


OBJECTIVE
Assess ethnic variations in response to IVF/ICSI treatment.


METHODS
Observational Comparative study in a University hospital fertility clinic in women with PCOS and Tubal factor subfertility. Women with PCOS (Asians: AP=104; Caucasians: CP=220) and those with tubal factor infertility seeking fertility treatment were assessed (Asians: AC=84; Caucasians: CC=200). Six hundred and eight fresh IVF or ICSI cycles using long protocol of GnRHa suppression and resulting in a fresh embryo transfer were compared. The primary endpoint was to assess the dose of gonadotropins used in the cycles. The secondary outcomes were: total number of oocytes retrieved, fertilization and ongoing clinical pregnancy rates.


RESULTS
We found that the South Asian women presented at a younger age for the management of sub-fertility. An extended stimulation phase and Caucasian ethnicity showed an inverse correlation with the number of oocytes retrieved in the PCOS subgroup. Caucasian ethnicity was associated with a higher fertilization rate however increase in body mass index (BMI) and the laboratory technique of IVF appeared to have a negative impact on fertilization rates in the PCOS subgroup. Commencing down regulation on day 1 of the cycles was negatively associated with fertilization rates in the tubal group. In terms of clinical pregnancy rates, the Caucasian PCOS had a 2.5 times (95% CI: 1.25-5) higher chance of an ongoing clinical pregnancy as compared with their Asian counterpart. Also, a unit increase in the basal FSH concentration reduced the odds of pregnancy by 18.6% (95% CI: 1.8-32.6%) in the PCOS group.


CONCLUSIONS
The Asian PCOS have a greater sensitivity to gonadotropin stimulation with lower fertilization and ongoing clinical pregnancy rates as compared with their Caucasian counterparts.
Palep-Singh
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Reproductive Medicine Unit, Leeds Teaching Hospitals NHS Trust, C Floor Clarendon Wing, Belmont Grove, Leeds LS2 9NS, UK. singhrajpal@hotmail.com
Picton
H M
HM
Vrotsou
K
K
Maruthini
D
D
Balen
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AH
D000328:Adult; D044466:Asian People; D004305:Dose-Response Relationship, Drug; D004359:Drug Therapy, Combination; D005260:Female; D006062:Gonadotropins / Q000008:administration & dosage*; D006801:Humans; D007247:Infertility, Female / Q000188:drug therapy / Q000208:ethnology* / Q000209:etiology; D010062:Ovulation Induction / Q000379:methods; D011085:Polycystic Ovary Syndrome / Q000150:complications / Q000208:ethnology*; D011247:Pregnancy; D011256:Pregnancy Outcome / Q000208:ethnology*; D018873:Pregnancy Rate / Q000208:ethnology; D020554:Sperm Injections, Intracytoplasmic; D006113:United Kingdom; D044465:White People
D006062:Gonadotropins