Purpose To better understand the characteristics of patients who returned to thaw their frozen eggs to attempt conception and their outcomes. Methods A retrospective analysis of clinical records for all own egg thaw patients in two UK fertility clinics across 10 years, 2008-2017. Results There were 129 patients who returned to thaw their eggs, of which 46 had originally frozen their eggs for social reasons and 83 for a variety of clinical, incidental, and ethical reasons (which we have called Bnon-social^). Women who had frozen their eggs for social reasons were single at time of freeze, with an average age of 37.7. They kept their eggs in storage for just under 5 years, returning to use them at the average age of 42.5. 43.5% were single at time of thaw, and 47.8% used donor sperm to fertilise their eggs. Women whose eggs were frozen for non-social reasons were almost all (97.6%) in a relationship at both time of freeze and thaw. They had an average age of 37.2 at first freeze and 37.6 at thaw, having kept their eggs in storage for an average of 0.4 years. Overall, there was a 20.9% success rate among women attempting conception with frozen-thawed eggs. Conclusions Despite widespread assumptions, many women attempting conception with thawed eggs had not initially frozen them for social reasons. Women who froze their eggs for social reasons presented distinctly and statistically different characteristics at both time of freeze and thaw to women whose eggs were frozen for non-social reasons.
Four distinct patterns in the ultrasonic appearance of preovulatory endometrium can be identified and described in patients undergoing stimulated cycles in an in vitro fertilization program. Ultrasonically, this endometrial response can be seen as a quantitative change in thickness and a qualitative change in gray-scale appearance or reflectivity. The application of this additional parameter of endometrial assessment together with the conventional measurement of follicular diameter as a means of optimally timing oocyte collection has been associated with a reduction in the preoperative ovulation rate from 10.9 to 3.2%, an increase in the fertilization rate from 59.2 to 82.5%, and in a pregnancy rate per embryo transfer of 20.5% in our program without the use of hormonal assays.
During fertilization in mammals, the male and female gametes undergo a form of highly complex cell-cell recognition whereby a nonspecific initial binding is followed by a species-specific penetration of the zona pellucida. Recent data from many species have demonstrated the involvement of surface carbohydrates in regulating fertilization at both these stages. The potential benefits as well as drawbacks of three major techniques used so far are discussed, and the need for a cautious interpretation of the data is emphasized. During capacitation, the carbohydrate components of the entire surface of spermatozoa undergo striking changes which may be linked to the concurrent metabolic events within motile spermatozoa, leading to the appearance of egg-specific glycoconjugates in a time-dependent manner. A multiple set of glycoproteins on the sperm surface, possessing oligosaccharides synthesized by the lipid-linked pathway, are probably required during different stages of fertilization, including sperm-oocyte fusion. The oviductal glycosaminoglycans may also be involved in regulating the timing and species specificity of mammalian fertilization by masking the sperm receptor sites on the zona and triggering the physiological acrosome reaction. Future biochemical and high-resolution localization studies involving specific probes for surface glycoconjugates, glycosyltransferases, and hydrolytic enzymes should greatly aid our understanding not only of the role of the individual surface macromolecules but also of the surface domains to which they are localized.
Shared motherhood IVF treatment is becoming increasingly accepted among assisted reproductive techique practitioners and patients in Europe, although data on its overall efficiency remain scarce. This 6-year retrospective study from a single, private, UK HFEA-regulated centre included consecutive lesbian couples (n = 121) undergoing shared motherhood IVF treatment (141 cycles). Recipients were more parous and had undergone more previous intrauterine insemination and IVF treatments than donor partners, who had slightly higher ovarian reserve markers than recipients. Indications in most cycles (60%) were non-medical. Most (79%) egg-providers were stimulated with gonadotrophin releasing hormone antagonist protocol, and no moderate or severe cases of ovarian hyperstimulation syndrome (OHSS) arose. A total of 172 fresh and vitrified-warmed embryo transfers were carried out: 70% at the blastocyst-stage and 58% involved a single embryo. Cumulative live birth rate per receiver was 60% (72/120), and twin delivery rate was 14% (10/72). Perinatal outcome parameters were better for singleton than twin pregnancies, although the latter also achieved generally favourable outcomes. No significant difference in cumulative outcomes were found between synchronized and non-synchronized cycles. Shared motherhood IVF combines ovarian stimulation with single blastocyst transfer to provide a safe and effective treatment modality offering reassuring obstetrical and perinatal outcomes.
The present acute shortage of eggs for donation cannot be overcome unless adequate guidelines are set to alleviate the anxieties regarding payments, in cash or kind, to donors. The current Human Fertilisation and Embryology Authority (HFEA) guidelines do not allow direct payment to donors but accept the provision of lower cost or free in vitro fertilization (IVF) treatment to women in recognition of oocyte donation to anonymous recipients. Egg-sharing achieved in this way enables two infertile couples to benefit from a single surgical procedure. However, the practical guidelines related to this approach are ill-defined at the present time leading to some justifiable uncertainty. A pilot study was therefore undertaken in order to establish the place of egg-sharing in an assisted conception programme. The current HFEA guidelines on medical screening of patients, counselling, age and rigid anonymity between the donor and recipient were followed. The study involved 55 women (25 donors and 30 recipients) in 73 treatment cycles involving fresh and frozen-thawed embryos. Donors were previous IVF patients who, regardless of their ability to pay, shared their eggs equally with matched anonymous recipients. They paid only for their consultations and tests right up to the point of being matched with a recipient. The sole recipient paid the cost applicable in egg donation of a single egg collection, although both received embryo transfers. The results indicate that although the recipients were older than the donors (41.4 +/- 0.9 versus 31.6 +/- 0.5 years), and there was no difference in the mean number of eggs allocated, the percentage fertilization rates, or the mean number of embryos transferred, there were more births per patient amongst recipients than amongst donors (30 versus 20%). We conclude that providing the donors are selected carefully, this scheme whereby a sub-fertile donor helps a sub-fertile recipient is a very constructive way of solving the problem of the shortage of eggs for donation. There are also the advantages of including a group of women who would otherwise be denied treatment. Problems related to 'patient coercion' can, in our view, be fully overcome by the application of strict common-sense safeguards. The ideal of pure altruism is not without its medical and moral risk. The success of egg-sharing depends on shared interests and a degree of altruism between the donor, the recipient and the centre. The current HFEA guidelines should be applauded for enabling a highly effective concept of mutual help to develop.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.