Intrauterine inseminations without twins: A new milder ovarian stimulation

Abstract

Objective: Multiple pregnancies represent a serious risk in ART procedures, especially in ovulation induction with and without intrauterine insemination (IUI). The aim of our study was to obtain monofollicular cycles and single pregnancies with a new milder method of ovarian stimulation, using low dose gonadotrophins and GnRH antagonist in IUI cycles. Design: Multicentric randomized clinical trial. Materials/Methods: Patients with at least two years of unexplained infertility or mild male factor were randomized in two groups: group A was treated with recombinant FSH (r-FSH) 50 IU daily (Puregon, Organon) starting from the third day of cycle; patients in group B received r-FSH 50 IU on alternate days. GnRH antagonist (Orgalutran, Organon) at the dose of 0,25 mg daily was started, in both groups, from mean follicle diameter of 13–14 mm at ultrasound. Daily serum E2 were obtained during GnRH antagonist therapy; in addition, serum LH and progesterone (P) were assessed in hCG day. No supplementation was given and serum E2 and P were dosed at +2, +4, +6, +8, +10 from hCG day. Results: A total of 47 patients were recruited. Thirty-six cycles in 36 patients were fully evaluable. Mean estradiol serum levels in each group showed a plateau on day one after GnRH antagonist administration, then had a normal increase. Twenty-one cycles were monofollicular (44,4% in group A and 72,2% in group B); no more than two leader follicles (≥16 mm in diameter) developed and in almost 80% of cases no follicles of 11–15 mm in diameter were present at hCG. Progesterone profile showed a normal ovulatory pattern in both groups. In the 36 completed cycles, pregnancy rate was 27,7%; with the daily FSH administration, group A patients had an unexpectedly high pregnancy rate (42%) compared to that registered in group B (10%)(p <0,05) (table). TableResults in 38 cyclesGroupP ≥ 8 ng/mlN. follicles ≥16 mmN. follicles ≥11 mmPregnancy12≥312≥3N. (PR)SingletonA18 (95)8 (44)10 (56)0 (0)4 (22)10 (56)4 (22)8 (42)†p < 0.058 (100)B18 (95)13 (72)5 (28)0 (0)9 (50)6 (33)3 (17)2 (10)2 (100)Numbers in brackets are percentages. P: Progesterone in mid-luteal phase. PR: Pregnancy Rate.† p < 0.05 Open table in a new tab Numbers in brackets are percentages. P: Progesterone in mid-luteal phase. PR: Pregnancy Rate. Conclusions: The daily low-dose gonadotrophin and GnRH antagonist regimen induced 58,3% monofollicular cycles and, most important, was constantly associated with singleton pregnancies. Pregnancy rate was significantly different for the two methods of stimulation, being the daily regimen more effective. GnRH antagonist had, nor in follicular neither in luteal phase, detrimental effect on the ovarian stimulation. The remarkably high pregnancy rate associated to monofollicular cycles, is probably related to the proper timing of IUI due to GnRH antagonist administration. Supported by: none.