Ovarian stimulation length, number of follicles higher than 17mm and estradiol on the day of hCG.
Authors: Nicolás Garrido, Marco Melo, Carlos Simón, José Remohí, Antonio Pellicer, Marcos Meseguer
(Reproductive Medicine and Biology 2007; 6: 19-26)
Our aim with this work was to identify the risk factors, their prognostic value on multiple pregnancies (MP) prediction and their thresholds in women undergoing controlled ovarian hyperstimulation (COH) with FSH and intrauterine insemination (IUI). We performed a case-control study by identifying in our database all the pregnancies reached by donor and conjugal IUI (DIUI and CIUI respectively) and compared cycle features, women characteristics, and sperm analysis results between women achieving single pregnancy (SP) versus MP.
The number of gestational sacs, follicular sizes, and estradiol levels on the hCG administration day, COH length and semen parameters were obtained from each cycle and compared. T-tests for mean comparisons, ROC curve analysis to determine the predictive value of each parameter on MP achievement, and multiple regression analysis to determine single parameter influence were conducted.
Women with MP in IUI stimulated cycles reached the adequate size of the dominant follicle (17mm) significantly earlier than those achieving SP. Also, the mean follicles number, and estradiol levels on the hCG day were higher in CIUI and DIUI MP group. Nevertheless, only ROC curve analysis revealed good prognostic value for estradiol and follicles higher than 17 mm. Multiple regression analysis confirmed these results. No feature of the basic sperm analysis either in the ejaculate, or in the prepared sample was different or predictive of MP. When using donor sperm, different thresholds of follicle number, stimulation length and estradiol in the prediction of MP were noted, in comparison with CIUI.
Subsequently, MPs in stimulated IUI cycles are closely associated to stimulation length, number of developed follicles higher than 17mm on the day of hCG administration and estradiol levels. Also, estradiol has a good predictive value over MP in IUI stimulated cycles. The establishment of clinical thresholds will certainly help in the management of these couples to avoid undesired multiple pregnancies by canceling cycles or converting them into in vitro fertilization procedures.
Keywords: IUI; multiple pregnancy; ovarian stimulation; sperm capacitation