Objective : To evaluate the effect of coasting in ovarian hypcrslimulatccl (ICSI) cycles on the outcome.
Design : Retrospective study.
Material and Methods : The study includes cases at risk of Ovarian Hypcrstimulalion Syndrome (OHSS). Coasting was applied when the patient was considered at actual risk of developing OHSS as indicated by, large number of follicles > 20 in both ovaries and serum E2 level > 3000 pg/ml. Coasting did not begin till the leading follicles reached a diameter of at least 15 mm and continued until Eo fell below 3000 pg/ml. Study group was divided into two groups based on the number of coasting days, group(I){ duration of coasting <4 days} and group(II){ duration of coasting >4 days) .
Result: Coasting was applied in twenty two patients out of one hundred seventy ICSI controlled ovarian hyperslimulaled cycles, during the period between April 2005 and April 2006. E2 level on day of initialing Coasting among group(I) and group(II) was 5162.9 ± 2891.9 pg/ml and 7198 ± 2313.3 pg/ml respectively (p value 0.26), \h level on day of HCG administration among group(I) and (II) was 2944.5 ± 12889 pg/ml and 2960 ± 2134.9 pg/ml respectively (p value 0.86), the mean number of oocyles and Mctaphasc II oocytes retrieved among group(I) were I 3 ± 4.9 and 10.4 ± 5.4 respectively and among group (II) were 5.6 ± 5.3 and 4.8 ± 3.9 respectively (p value 0.008); the mean fertilization rale among groups(I) & (II) was 69 % & 68% respectively, the mean number of embryos among groups(I) & (II) was 7.5 ± 3.1 & 4 ± 3.5 respectively, pregnancy rale per embryo transfer among groups (I) & (II) was 28.8 % & 0.0 % respectively and OHSS 0.58% (1/170) of stimulated cycles and 4.54 % (1/22) of patients at risk of developing OHSS
Conclusion: Coasting is effective in preventing OHSS and allow transfer of fresh embryos, without cycle cancellation. Prolonged Coasting ( >4 days) may be detrimental to the quality of Oocytes , fertilization rate and pregnancy rate.