1 Introduction
Polycystic ovary syndrome (PCOS) is the most common endocrine condition in women of reproductive age, with a incidence rate of 5%–10%,1 and is the major cause of anovulatory infertility.2 Conventional treatment is ovulation induction with clomiphene citrate.3 Other ovulation induction interventions include insulin-sensitizing drugs, aromatase inhibitors, gonadotropins, and laparoscopic ovarian drilling.4–6 Anti-mullerian hormone (AMH) inhibits follicle-stimulating hormone(FSH)-dependent follicle selection and aromatase expression, resulting in increased androgen levels. Because clomiphene stimulates ovulation by increasing FSH levels, AMH and androgen levels can interfere with its response. Calculated free testosterone, calculated bioavailable testosterone or free androgen index (FAI) could be used to assess biochemical hyperandrogenism in PCOS. Previous studies have indicated that high AMH and FAI levels are associated with poor response to ovulation induction in PCOS women. The cut-off value of AMH for response to ovulation induction varies from 1.2 ng/ml to 7.7 ng/ml.7 Hyperandrogenaemia is also associated with poor response to ovulation induction.8 This prospective study explores the relationship between FAI and AMH level on ovarian responsiveness to clomiphene citrate in infertile women with PCOS.
1.1 Methods
After institutional research and ethical committee clearance, a prospective observational study was conducted. The sample size was determined to be 40 (n Master version 2.0) based on the sensitivity of AMH to predict successful ovulation as 97.2%8 with 5% absolute precision and 95% confidence interval. The population studied were patients who came to our gynecology department for infertility treatment. The inclusion criteria were women with primary infertility due to PCOS in the age group of 19–35 years with patent fallopian tube and a normal uterine cavity, as determined by hysterosalpingogram or sonosalpingography and male partner with normal semen analysis according to WHO 2010 guidelines criteria.9 Ovulatory dysfunction was diagnosed when menstrual cycles were < 21 or > 35 days or < 8 cycles per year or > 90 days for anyone cycle. FAI >5 was considered biochemical hyperandrogenism. Hirsutism was defined as a modified Ferriman- Galleway score of more than 6. Clinical diagnosis of acanthosis nigricans (AN) was made by noting dark velvety patches on the posterior neck/axilla. Polycystic ovarian morphology (PCOM) was diagnosed with transvaginal ultrasound when there were >20 follicles per ovary or ovarian volume ≥10 ml ensuring no corpora lutea, cysts, or dominant follicles.10 The National Institutes of Health (NIH) evidence-based methodology workshop of PCOS 2012 recommended that specific phenotypes should be reported explicitly in all research.11 Clinical/biochemical hyperandrogenism (HA), ovulatory dysfunction (OD), and PCOM are features of PCOS. Phenotype A has all three features HA, OD, and PCOM; phenotype B has HA and OD; Phenotype C has HA and PCOM; Phenotype D has OD and PCOM.
Body mass index (BMI) and waist: hip ratio was categorized using WHO cut-off points for the Asian population.12 On day 2 of a spontaneous menstrual cycle or after a withdrawal bleed, 5 ml of blood was drawn to measure AMH, total testosterone, serum sex hormone-binding globulin (SHBG), follicle stimulating hormone (FSH), luteinizing hormone (LH), thyroid stimulating hormone (TSH), and prolactin. Plasma was separated within 2 h of venipuncture, stored in aliquots at – 70 °C until thawed, and analyzed in batches. On the same morning, all the participants underwent transvaginal ultrasound (6 MHz transducer (Siemens –Acuson X300, Model: KT-LM150XD, USA) 0 to note the number of early antral follicles measuring 2–6 mm in diameter. Serum total testosterone and SHBG were determined using SIEMENS ADVIA CENTAUR-CP immunoassay. The free androgen index was determined as the ratio of total testosterone divided by SHBG and multiplied by 100.
On day 2 of a spontaneous menstrual cycle or after a withdrawal bleeding, participants received an incremental dose of clomiphene citrate ranging from 50 mg to 150 mg for five days. Follicular tracking was started on day 9 using transvaginal ultrasound and continued until the rupture of the dominant follicle. The clomiphene dose at which the ovulation occurred and endometrial thickness (ET) were documented. Women who ovulated with clomiphene were referred to as clomiphene-sensitive. Women who failed to ovulate with 150 mg of clomiphene were referred to as clomiphene-resistant.
1.2 Statistical analysis
Data was entered into a Microsoft Excel datasheet and analyzed using SPSS 22 software. Categorical variables were represented in the form of frequencies and percentages. The normal distribution of continuous variables was determined using a Q-Q plot. Continuous variables were expressed using mean and standard deviation. Continuous and categorical variables were compared using Pearson's Chi-square and unpaired t-test.