Leon A. Sheean

Preliminary experience with in vitro fertilization-surrogate gestational pregnancy

This report documents the medical details and 3-year follow-up evaluation of the infertile and surrogate couples involved in the first successful in vitro fertilization gestational surrogate pregnancy and summarizes clinical experience and outcome of all patients treated to date. Results of the first 28 couples treated are presented. The pregnancy rate for 39 cycles reaching attempts at oocyte retrieval is 18%. The procedural aspects, ethical issues, legal issues, and subsequent program development are summarized. Recommendations are of a similar program. There are numerous potential pitfalls and traps for the unwary, but our experience has thus far been gratifyingly positive, and we endorse the further provision, observation, and documentation of this controversial approach to the care of the infertile couple.

The effect of Y-chromosome alpha-satellite array length on the rate of sex chromosome disomy in human sperm.

Trisomy is the leading known cause of mental retardation and pregnancy loss in humans, yet virtually nothing is known of the underlying nondisjunctional mechanisms. Since studies of other organisms suggest an association between centromere size or sequence and meiotic nondisjunction, we recently initiated studies to examine the effect of centromere size variation on human nondisjunction. In the present report, we summarize studies correlating variation in the size of the Y-chromosome centromere with sex chromosome nondisjunction. In one set of studies, we used pulsed-field gel electrophoresis to estimate Y-chromosome alpha-satellite array lengths in normal males, and correlated these values with Y-chromosome sperm disomy levels as determined by fluorescence in situ hybridization. In a second set of studies, we determined the Y-chromosome alpha-satellite array length of 47,XYY males, since the karyotypes of these individuals are a consequence of Y chromosome nondisjunction. Neither set of studies provided evidence for an effect of Y-chromosome alpha-satellite array length on Y-chromosome nondisjunction. Thus, if there is an association between Y-chromosome centromere size and nondisjunction, the effect is subtle and below the detection levels of the present study or involves extreme size variants that were not represented in the present study population.

Clinical Experience with Synthetic Serum Substitute as a Protein Supplement in IVF Culture Media: A Retrospective Study*

AbstractObjective: Our objective was to evaluate the efficacy of Synthetic Serum Substitute (Irvine Scientific—Materials Section, Santa Ana, CA), a globulin-enriched protein preparation containing human serum albumin for supplementation of IVF culture media. Design: We retrospectively analyzed IVF cycles performed at MacDonald Womens Hospital between January 1992 and November 1994. IVF cycles were reviewed and classified according to the nature of protein supplementation used in the embryo culture medium. Three protein supplements utilized during this time period were compared: Synthetic Serum Substitute (SSS), Plasmanate (PL), and maternal serum (MS). Results: Although clinical pregnancy rates among the three treatment groups were not statistically different, there was a definite trend toward a higher pregnancy rate with SSS supplementation (SSS, 38.2%; MS, 28.0%; and PL, 24.9%). Embryos grown in SSS-supplemented culture media had a significantly higher implantation rate (17.8 vs 10.4 and 10.3%, respectively, for MS and PL). Preliminary data also suggest that human embryo development and blastulation in vitro were enhanced by this protein supplement. Conclusions: The higher implantation rate with SSS suggests that it may be superior to both maternal serum and Plasmanate in supporting human embryo development in vitro. Whether blastocysts derived from PL- and SSS-supplemented media are able to implant and give rise to clinical pregnancies remains to be seen.

Implementation of an in vitro fertilization program

The establishment of an in vitro fertilization program is described. Organization of the physical laboratory, media formulation, and preliminary mouse embryo culture are discussed. Parameters of patient eligibility, ovarian stimulation, and laporoscopy are also defined. At the conclusion of Phase I, 17 patients were induced; 10 went to laparoscopy, and at least one four-cell embryo was returned to 7, resulting in one continuing pregnancy.

In vitro fertilization (IVF)-surrogacy: Application of IVF to women without functional uteri

Women with absent or dysfunctional uteri consented to controlled ovarian stimulation, ovum aspiration, in vitro fertilization, and embryo culture. Cleaving preembryos were transferred to recipient (surrogate) women whose menstrual cycles were in approximate synchrony with the ovum donor. None of the embryo recipients received medication. Six cases are described, resulting in one spontaneous loss at 6 weeks, four full-term deliveries, and one ongoing pregnancy. HLA typing demonstrated all babies to be genotypic offspring of the gamete donors.

Limiting multiple pregnancy in in vitro fertilization/embryo transfer (IVF-ET) cycles.

AbstractPurpose: Our purpose was to assess how the number of embryos transferred can be adjusted to limit multiple gestations. Methods: A retrospective analysis of 535 consecutive embryo transfers for the years 1991–1993 was conducted. Results: Fewer than three embryos were associated with a low pregnancy rate. Pregnancy rates were highest in women less than 35 when four or more embryos were transferred. With four or more embryos, multiple gestation pregnancy correlated with the number of high-quality embryos transferred. The risk of triplets and quadruplets was greatest for women less than 40. Conclusions: Multiple-embryo transfer carries a risk of plural gestation. The risk of multiple pregnancy cannot be eliminated without decreasing the pregnancy rate. The risk of high-order multiple pregnancy was best correlated with the number of good-quality embryos transferred. While all are at risk, patients younger than 40 were at highest risk.

Inhibitor specificity of the placental microsomal oxidase system responsible for the aromatization of epitestosterone (17α-hydroxy-4-androsten-3-one)

Human placental microsomes converted epitestosterone to estradiol-17 alpha at rates of 23-48 pmol/min X mg protein with a Km of 113 microM. Activity was inhibited 70-90% by concentrations of CO, metyrapone, n-octylamine, 7,8-benzoflavone and 7-ethoxycoumarin which had no effect on the aromatization of 4-androstene-3, 17-dione. Conversely, cyanide and azide were more effective inhibitors of the conversion of the latter androgen. A variety of neutral steroids inhibited the aromatization of epitestosterone with 19-norsteroids being particularly effective, but competitive effects could not be demonstrated. Both 17 beta-hydroxy-4-estren-3-one and 16 alpha-hydroxy-4-androstene-3,17-dione caused a mixed inhibition. A number of phenolic steroids were also inhibitory with 16-oxo compounds being particularly effective. Inhibition by estrone was non-competitive (Ki = 16 microM). The aromatization of epitestosterone resembles placental microsomal oxidase activities against estrone and benzo [a]pyrene in its inhibitor specificity and epitestosterone may be the native substrate for an oxidase also active in the metabolism of aromatic xenobiotic chemicals.

Quantitative requirements for NADPH in the support of aromatization by human placental microsomes

Suitable incubation conditions were developed for reduced pyridine nucleotide protection and regeneration to permit quantitative assessment of the NADPH requirement for steroid aromatization by human placental microsomes. 10 mM dithiothreitol was found to protect NADP(H) from microsomal nucleotide pyrophosphatase and 2 mM nicotinamide mononucleotide was utilized to control nucleotide glycohydrolase activity. Under these assay conditions, the initial rates of aromatization obtained with restricted NADPH levels were critically dependent upon both the amount and the source of exogenous NADPH-regenerating dehydrogenase system. With excess Leuconostoc mesenteroides glucose-6-phosphate dehydrogenase, an apparent Km for NADPH of 0.20 microM was observed for aromatization which is significantly below all previous estimates of the NADPH requirement and which is at greatest only one-tenth the Km value for NADPH utilization by NADPH-cytochrome c reductase. These findings suggest a potential regulatory role for both NADPH-generating and NADPH-accepting enzymes in the support of estrogen biosynthesis.

In Vitro Fertilization — Surrogate Gestational Pregnancy

The purpose of this presentation is to review our early experience with in vitro fertilization, surrogate gestational pregnancy, a program that has resulted in a world medical and legal first.1,2