A prospective dose-finding study of the amount of thermal energy required for laparoscopic ovarian diathermy

This prospective dose-finding study was undertaken to determine the optimal amount of thermal energy required for laparoscopic ovarian diathermy (LOD) in women with polycystic ovary syndrome (PCOS).

Thirty women with clomiphene-resistant PCOS were included in the study. All women underwent LOD. A modified Monte Carlo up-and-down design was utilized. Women were treated in groups of three (10 groups). The amount of energy applied was standardized at 150 J/puncture. The number of punctures in each group was decreased/increased according to the number of responders in the previous group. The main outcome was ovulation as defined by a serum progesterone concentration of > or =30 nmol/l.

Four groups (n=12) were treated with four punctures/ovary, three groups (n=9) with three punctures, two groups (n=6) with two punctures and one group (n=3) with one puncture. Ovulation occurred in 67, 44, 33 and 33% of women treated with four, three, two and one puncture/ovary respectively. The corresponding pregnancy rates were 67, 56, 17 and 0%. The reductions in the free androgen index and the serum concentrations of testosterone and androstenedione after LOD were observed only in women treated with three and four punctures/ovary.

The clinical response to LOD seems to be dose-dependent, with an increase in the frequency of ovulation and conception with an increasing dose of thermal energy up to 600 J/ovary.