Nathan Lewit

Assessment of ovarian and uterine blood flow by transvaginal color Doppler in ovarian-stimulated women: correlation with the number of follicles and steroid hormone levels.

OBJECTIVE To study the changes that occur in vascular resistance to flow in the utero-ovarian circulation and their correlation with the number of follicles and steroid hormone levels in patients undergoing ovarian stimulation with gonadotropin. DESIGN In a prospective study, the impedance to flow in the intraovarian and uterine vessels was measured by means of transvaginal color flow Doppler imaging throughout the cycle. SETTING University-based IVF program. PATIENTS Eleven infertile patients undergoing ovarian stimulation with gonadotropin in preparation for IVF and ET. MAIN OUTCOME MEASURES Intraovarian, uterine, and arcuate artery blood flow velocity waveforms, follicular growth, and serum E2 and P concentrations throughout the cycle. RESULTS Pulsatility index (PI) of the intraovarian blood vessels and uterine artery decreased gradually during the follicular and luteal phase. The PI of the arcuate artery did not change significantly. The PI of the intraovarian blood vessels correlated with the number of follicles (> 15 mm; day of hCG). Serum E2 concentrations but not P demonstrated negative linear correlation with the PI of the intraovarian vessels and uterine artery. CONCLUSIONS Induced cycles are associated with decreased impedance to blood flow in the utero-ovarian circulation. Intraovarian PI correlates negatively at each stage of the cycle with the eventual number of preovulatory follicles. Little or no changes are observed when the response to ovarian stimulation is poor.

The natural history of multiple pregnancies after assisted reproduction: is spontaneous fetal demise a clinically significant phenomenon?

OBJECTIVE To determine the rate of spontaneous fetal demise after heartbeats are demonstrated in multiple pregnancies conceived after IVF-ET. DESIGN Retrospective case series. SETTING University-based IVF-ET program. PATIENTS Eighty-one patients in whom initial transvaginal ultrasound (US) study, performed at 5 to 6 weeks of gestation, identified more than one gestational sac. Total number of sacs was 191. INTERVENTION Patients were followed by serial US examinations. MAIN OUTCOME MEASURE Outcome of pregnancies. RESULTS Twenty-four empty gestational sacs were identified in 21 patients, of whom 15 delivered, 2 miscarried, and 4 are currently ongoing beyond first trimester. Of the 167 initially viable embryos, 9 (5%) underwent spontaneous fetal demise. In 5 of these 9 pregnancies, initial US identified significant interfetal size variation. CONCLUSIONS The rate of spontaneous fetal demise for a specific embryo in multiple gestation, after fetal heartbeats have been identified in early pregnancy, is 5%. This rate is similar to that seen in spontaneous conceptions. The chance of future fetal demise increases if first trimester interfetal size variation is significant.

Does intravenous administration of human albumin prevent severe ovarian hyperstimulation syndrome

OBJECTIVE To report our experience with i.v. albumin as a means to prevent ovarian hyperstimulation syndrome (OHSS) in high-risk patients. DESIGN Retrospective case-series. SETTING University hospital-based IVF program. PATIENTS Five women undergoing controlled ovarian stimulation for IVF-Based on previous history and/or E2 measurements and number of ovarian follicles, these patients were considered to be at high risk for developing OHSS. INTERVENTIONS Intravenous albumin was given at the time of oocyte retrieval. Additional doses were given 12 and 24 hours later. MAIN OUTCOME MEASURE Development of OHSS. RESULTS Four patients developed OHSS; two of them had the severe form of the syndrome. CONCLUSIONS Severe OHSS may develop in high-risk patients despite the prophylactic administration of i.v. albumin.

The use of GnRH analogs for induction of the preovulatory gonadotropin surge in assisted reproduction and prevention of the ovarian hyperstimulation syndrome

Ovarian hyperstimulation syndrome (OHSS) remains a potential severe complication of the use of gonadotropin therapy in ovulation induction and assisted reproduction technologies. In 1988, we reported preliminary results which demonstrated the ability of gonadotropin-releasing hormone analogs (GnRH-a) to trigger ovulation, and to prevent subsequent OHSS. In this report, we summarize our experience of 73 treatment cycles involving 44 high responders (i.e. patients with a previous history of severe OHSS, or with high estradiol levels (> 13 200 pmol/l) on the day of triggering the luteinizing hormone (LH) surge).In spite of the high estradiol levels (mean 24 202 pmol/l) and the large number of oocytes (mean 32.4), none of our patients developed severe OHSS. Luteal support with progesterone and estradiol valerate was necessary to maintain adequate serum levels of these hormones. Without such support, a precipitous decline in levels of estradiol and progesterone was observed. We believe that the use of GnRH-a i...

The low responder, hypogonadotropic hypogonadism female patient in IVF: do not give up!

Hypogonadotropic hypogonadism (HH) is one of the least common etiologies for female infertility, although treatment in most cases leads to successful conception. The development of urinary-derived gonadotropins (hMG) a few decades ago paved the way to replacing the absent endogenous hormones (1, 2). Other alternatives to therapy include native GnRH or recombinant FSH, although the use of the time-honored hMG preparations leads in most cases to ovulation (3). It is of interest that the average treatment duration and the number of ampules used are higher compared with patients with other etiologies of infertility (2). This may be explained by the “dormant” ovaries that need to be primed before follicular response is achieved.