During natural cycle in vitro fertilisation, no gonadotropin stimulation is used to stimulate oocyte production. Ovulation is induced with HCG (human chorionic gonadotropin) and the follicle is retrieved 36 hours later. In this study the patient in the intervention group will receive Ibuprofen as a study intervention beginning at the same time as the HCG injection. The treatment dose will either be 400mg every 8 to 12 hours or 800mg every 8 to 12 hours until the follicle retrieval, totalling 5 tablets. Instead of the usual time period of 36 hours, the follicular punction will occur after 42 hours. Should the oocyte still be accessible after this time period, then it is proven that Ibuprofen delays ovulation. In this case the patient will continue the regular NC-IVF treatment cycle. The study design is a admissible two-stage design. During stage 1, 8 cycles in 8 patients will be examined. Should it be the case that after these 8 patients have completed a cycle, 4 or more show a positive treatment effect from the Ibuprofen intake, then the study will continue to stage 2 with 17 more more patients, totalling 25. Should it be the case however, that after 8 patients, 3 or less show an effect of the Ibuprofen intake, then the study will be stopped prematurely for futility. The study intervention will be increased to 800mg of Ibuprofen and the study will recommence with 8 more patients. A control group will consist of women undergoing intrauterine insemination (IUI) or timed sexual intercourse (TSI). 42 hours after Beta-HCG injection, an ultrasound examination will be performed in order to determine the number of remaining follicles in the ovary. This examination is to verify and control the proposed time limit of 42 hours.
Age range
18 Years – 42 Years
Sex
FEMALE
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A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
Percentage of non ovulated follicles
Timeframe: 42 hours after HCG injection