Reply of the authors: Uterus transplantation in nonhuman primates

8 04 2013

To the Editor:

It was encouraging to see that our article on uterine transplantation in nonhuman primates was discussed on the editorial page. We believe that it is important for attainment of clinical application to validate uterine transplantation in primate models. We agree with many of the comments made by Dr. Tzakis (1). These comments accurately identify challenges specific to the background of uterine transplantation experiments in primates.

First, uterine transplantation is conducted for improved quality of life, which differs from transplantation of organs for life support. Organ transplantation started decades ago; however, studies of the uterus were rare because uterus dysfunction is not life-threatening. However, the bioethical view has changed over time and with technology development, the number of uterine cancer survivors has increased, with a corresponding need for improved postoperative quality of life. Consequently, uterine transplantation with the goal of delivery in patients with uterine factor infertility is of increasing importance. It is clear that such patients cannot deliver a child without intervention, and many also lose female identity or may experience marital problems, resulting in psychological and social distress. Uterine transplantation has the potential to improve quality of life by providing the potential for pregnancy and delivery with assisted reproductive technology (ART). Read the rest of this entry »

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Whatever its variability, AMH remains the most stable hormonal predictor

8 04 2013

To the Editor:

Dr. Hadlow and colleagues argue that antimüllerian hormone (AMH) levels decrease in the luteal phase and that the hormone should be measured in the follicular phase, since this variability may lead to misprediction of ovarian response in IVF. This assumption was made on the basis of few, not frequent, blood samples performed on a very limited sample of women (1).

In the study, the intra-individual variability of AMH was found to be similar to that of FSH. This finding is really surprising and points out a critical revision of the results obtained. Both of the largest available studies to date (2, 3) reported that 89% of the variation in AMH was due to between-subjects variation, while only 11% was due to true individual fluctuations. AMH may exhibit some variability, but the important point is that the fluctuations are randomly distributed throughout the menstrual cycle (4), raising the possibility that a fixed day for its measurement, as proposed, would be useless. The suggested cyclic moifications of AMH in Dr. Hadlow’s study need to be confirmed in studies investigating hormonal variability through more frequent samples and across at least two menstrual cycles. A logical and agreeable hypothesis explaining why AMH should reduce in the luteal phase needed to be formulated by the authors. If AMH is produced by antral follicles, the number of which shows no significant reduction in the luteal phase, and since AMH seems to be only marginally influenced by gonadotropins, why should its concentration reduce in the second part of the cycle? Read the rest of this entry »





“Reply of the authors: Uterus transplantation in nonhuman primates”

8 04 2013

To the Editor:

It was encouraging to see that our article on uterine transplantation in nonhuman primates was discussed on the editorial page. We believe that it is important for attainment of clinical application to validate uterine transplantation in primate models. We agree with many of the comments made by Dr. Tzakis (1). These comments accurately identify challenges specific to the background of uterine transplantation experiments in primates.

First, uterine transplantation is conducted for improved quality of life, which differs from transplantation of organs for life support. Organ transplantation started decades ago; however, studies of the uterus were rare because uterus dysfunction is not life-threatening. However, the bioethical view has changed over time and with technology development, the number of uterine cancer survivors has increased, with a corresponding need for improved postoperative quality of life. Consequently, uterine transplantation with the goal of delivery in patients with uterine factor infertility is of increasing importance. It is clear that such patients cannot deliver a child without intervention, and many also lose female identity or may experience marital problems, resulting in psychological and social distress. Uterine transplantation has the potential to improve quality of life by providing the potential for pregnancy and delivery with assisted reproductive technology (ART). Read the rest of this entry »





Comments on the article “Intracytoplasmic sperm injection outcome of ejaculated versus extracted testicular spermatozoa in cryptozoospermic men”

2 04 2013

To the Editor:

I have read your article “Intracytoplasmic sperm injection outcome of ejaculated versus extracted testicular spermatozoa in cryptozoospermic men” (1) with great interest. The subject is a matter of current debate in the treatment of male factor infertility, and the results of this study should therefore be considered with attention.

In this retrospectively designed study, you have assessed 17 patients with cryptozoospermia who underwent a total of 116 ICSI cycles with either ejaculated (n=68; 58.6%) or testicular sperm (n=48; 41.4%, 31 fresh and 17 frozen cycles) between January 2010 and December 2011 in your IVF unit. These patients initially underwent a mean of 4.1±2.4 ICSI cycles using ejaculated sperm that were followed by ICSI cycles using either fresh (1.4±1.1 cycles) or frozen (1.7±0.6 cycles) testicular sperm cycles.

You found that there were no significant differences in fertilization rates between the two subgroups. A comparison between testicular sperm extraction (TESE) versus ejaculated sperm cycles revealed a significantly higher implantation rate (20.7% vs. 5.7%), higher PR (42.5% vs. 15.1%), and a higher take-home baby rate (27.5% vs. 9.4%). You also showed that there was a trend of higher mean number of day 2 embryos per cycle in the TESE cycles compared with the ejaculated sperm cycles (5.2±5.6 vs. 3.2±3.4; P=0.058), and the cleavage rate of day 2 embryos was significantly lower when ejaculated sperm cells were used compared with TESE cycles (3.5±1.1 vs. 3.9±0.7; P=0.026). Similarly, the cleavage rate of day 3 embryos was significantly lower after ICSI using ejaculated sperm cells compared with TESE cycles (5.3±1.4 vs. 6.7±1.5; P=0.028). As a result, a significantly higher mean number of embryos were transferred to the uterus in the TESE cycles compared with the ejaculated sperm cycles (2.5±1.5 vs. 1.8±1.2; P=0.011). However, there were no statistically significant differences between the two subgroups in the mean morphology scores of day 2 and 3 embryos, as well as the mean number of cryopreserved embryos. Read the rest of this entry »