Assessing the Convenience of Natural Proliferative Phase Frozen Embryo Transfer: an Ambispective Cohort Study
试验速览
- 阶段
- 不适用
- 状态
- 招募中
- 发起方
- 入组人数
- 530
- 试验地点
- 1
- 主要终点
- Number of appointments needed before cycle scheduling
研究概览
简要总结
This study will assess the convenience of the natural proliferative phase frozen embryo transfer (NPP-FET) in terms of number of number of appointments needed before cycle scheduling.
详细描述
Frozen embryo transfer (FET) is increasingly used nowadays in Assisted Reproductive Techniques (ART) clinics. Several factors account for this uprising. Among them, the concept of ovarian hyperstimulation syndrome (OHSS)-free clinic, the increasing use of preimplantation genetic testing (PGT), the improved vitrification systems, and the growing evidence regarding similar, or even better, pregnancy rates when FET are compared to fresh embryo transfers.
In the last few years, research has focused on the selection of the best protocol for endometrial preparation in patients undergoing FET cycles. Despite the accumulating evidence suggesting similar reproductive outcomes following both artificial cycle (AC-FET) and natural cycle (NC-FET) protocols, AC-FET is frequently adopted in ART centers due to its convenience in terms of cycle scheduling. However, a role for the corpus luteum in the maternal vasodilatory changes of early pregnancy has recently been associated with a decreased risk of pre-eclampsia. In fact, several large cohort studies have reported a higher risk of hypertensive diseases of pregnancy, macrosomia, post-term delivery and cesarean section following AC-FET.
The NPP-FET protocol is a strategy that potentially allows for cycle scheduling while maintaining the benefits of the natural cycle in terms of pregnancy outcomes. The main goal of the present study is to analyze its convenience in terms of the number of appointments needed before FET scheduling by comparing it with the NC-FET protocol. Additionally, the investigators aim to compare the reproductive outcomes between the two strategies and to analyze whether NPP-FET patients undergo ovulation.
Briefly, the study group will prospectively recruit ovulatory patients who will perform vaginal ultrasound monitoring will be performed on cycle day 8-12, depending on the length of the patients' menstrual cycle. When the endometrial thickness is at least 7 mm and the dominant follicle is at least 13 mm, vaginal micronized progesterone will be initiated at 400mg every 12 hours. One embryo will be transferred on the fifth day of progesterone supplementation under ultrasound guidance. The control group will include a retrospective cohort of ovulatory patients who underwent NC-FET.
研究设计
- 研究类型
- Observational
- 观察模型
- Cohort
- 时间视角
- Other
入排标准
- 年龄范围
- 18 Years 至 49 Years（Adult）
- 性别
- Female
- 接受健康志愿者
- 否
入选标准
- •Endometrial thickness ≥ 7 mm on the day of starting progesterone-based luteal phase support (LPS)
- •Serum progesterone levels <1.5 ng/ml on the day of starting progesterone-based LPS
- •LPS with micronized progesterone 400mg b.i.d.
- •Regular cycles (>24 days, ≤ 38 days)
- •IVF/ICSI with donated oocytes
- •Single blastocyst stage embryo transfer
- •First or second embryo transfer from the same cohort
排除标准
- •Use of exogenous ovarian stimulation during FET
- •Untreated hydrosalpinx, polyp, submucous myomas or severe adenomyosis
- •Recurrent pregnancy loss (≥ 3 previous pregnancy losses)
- •Recurrent implantation failure with embryos from oocyte donation (≥ 3 previous failed embryo transfers)
- •Personalized initiation of exogenous progesterone according to a previous endometrial receptivity assay test
研究组 & 干预措施
Natural proliferative phase frozen embryo transfer (NPP-FET)
When the endometrial thickness is at least 7 mm, vaginal micronized progesterone will be initiated at 400mg every 12 hours, as per standard clinical practice, when the dominant follicle is at least 13 mm, serum estradiol (E2) levels are >80 pg/ml, and serum progesterone levels are <1.5ng/ml. One embryo will be transferred on the fifth day of progesterone supplementation under ultrasound guidance. Progesterone will be continued until the 11th week of pregnancy.
干预措施: Natural proliferative phase frozen embryo transfer (Procedure)
Natural cycle frozen embryo transfer (NC-FET)
When the mean dominant follicle diameter was at least 17 mm and the endometrial thickness was at least 7 mm, serum E2, progesterone and luteinizing hormone (LH) were evaluated. If a spontaneously LH peak was detected (E2>80 pg/ml, LH peak >18 mIU/mL with progesterone level <1.5 ng/mL), vaginal micronized progesterone was started from the evening of ovulation at a dose of 200 mg every 12 hours. Conversely, whenever a LH peak was not detected (E2>80 pg/ml, LH <18mIU/ml and progesterone <1,5 ng/ml), r-hCG 250µg (Ovitrelle®) was administered subcutaneously, followed, 48 hours later, by daily administration of 200 mg micronized vaginal progesterone every 12 hours. One embryo was transferred 7 days after r-hCG administration or 6 days after LH peak detection. Progesterone was continued until the 8th week of pregnancy.
结局指标
主要结局
Number of appointments needed before cycle scheduling
时间窗: Up to three weeks
Number of visits for cycle monitoring until embryo transfer scheduling
次要结局
- Live birth rate(40 weeks after ET)
- Cycle duration until embryo transfer (days)(Up to four weeks)
- Proportion of patients with low progesterone values on the day of embryo transfer(One day)
- Human corionic gonadotropin (hCG) positive rate(10-14 days after ET)
- Miscarriage rate(Up to 20 weeks after ET)
- Ongoing pregnancy rate(9-11 weeks after ET)