A new mutation, 3905insT, accounts for 4.8% of 1173 CF chromosomes in Switzerland and causes a severe phenotype

The objective of this study was to determine the predictive value of the number of follicles seen by transvaginal ultrasound before gonadotrophin stimulation on the ovarian responsiveness of 166 infertile women undergoing in-vitro fertilization (IVF) treatment. The main variables were patient age, ovarian volume and number of ovarian follicles measuring 2-5 mm on transvaginal ultrasound before gonadotrophin stimulation. Based on the sum of ovarian follicles in both ovaries the patients were divided into three groups of inactive (<5 follicles), normal (5-15 follicles) or polycystic (PCO)-like ovaries (>15 follicles). The main outcome measure was the number of recovered oocytes. The number of follicles was correlated more strongly with the number of recovered oocytes (r2 = 0.131; P = 0.0001) than age alone (r2 = -0.053; P = 0.005). Fewer oocytes were recovered from patients with inactive ovaries (5.4 +/- 2.5; P = 0.006) than with normal (7.5 +/- 4.5) or PCO-like ovaries (10.5 +/- 5.1). Ovarian volume was correlated with the number of follicles before stimulation (P = 0.0001), but not with the number of oocytes. The number of small follicles present before ovarian stimulation was a better predictor of the outcome than ovarian volume or age alone. Patients can be identified with inactive ovaries which will have a poor response to IVF treatment, a key factor for counselling couples and optimizing resources.