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991.
Purpose To determine the demand and preferences of infertility patients for sex selection for nonmedical reasons, and to investigate
the relation between these choices and their demographic and socioeconomic characteristics.
Methods A cross-sectional, self-administered survey by mail was conducted at a University hospital-based fertility center of 1,350
consecutive women who presented for infertility care, to assess patient demand and preferences for sex selection.
Results Of respondents, 49% wanted to select the sex of their next child for no added cost. Of these patients, 56% had no living children
and 37% had children all of one sex. After adjustment for observed predictors of gender preference, we found a significant
preference for a female child among women who had only sons, had more living children, or were single. Nulliparous women did
not significantly prefer one sex over the other. Among parous women, those with only daughters significantly desired to select
a male child, whereas those with sons significantly desired to select a female child.
Conclusion There is significant demand among infertility patients for preimplantation sex selection, with a significant portion of this
demand coming from patients who do not have any children or have children all of one sex.
Presented in part at the American Society for Reproductive Medicine (ASRM) Annual Meeting, New Orleans, Louisiana, October
2006.
Financial support: none
Conflict of interest: none 相似文献
992.
Seth S 《Journal of assisted reproduction and genetics》2007,24(5):153-154
Regarding sex selective abortion in India, all are aware of exclusive female disadvantage. And yet few study reported sizeable
selective male feticide as such. This exercise reveals that: (1) the age-old son-preference has slightly declined on the end
of the twentieth century, and (2) a substantial selective male feticide are also being committed annually, of course, along
with larger selective female feticide. 相似文献
993.
Zohav E Orvieto R Anteby EY Segal O Meltcer S Tur-Kaspa I 《Journal of assisted reproduction and genetics》2007,24(6):259-261
PURPOSE: To evaluate the role of 3-D US measurement of the endometrium during early IVF-pregnancy and before the appearance of gestational sac in the prediction of pregnancies outcome. METHODS: 60 pregnant women following IVF treatment were included in the study. The women underwent transvaginal 3D US measurements of endometrial volume and thickness on day 15-17 post ET. Patients were followed and classified according to pregnancy outcome into 2 further groups. The group with early pregnancy loss and the group with ongoing pregnancy. RESULTS: While no differences were observed between those who miscarried and those who did not in gestational age, endometrial thickness or volume, spontaneous early pregnancy loss was significantly higher in patients with endometrial volume <2 mL as compared to those with endometrial volume >2 mL. CONCLUSIONS: 3-D US measurement of endometrial volume of less than 2 mL during early IVF pregnancy and prior to the appearance of gestational sac is a powerful predictor of pregnancy loss. 相似文献
994.
Background
Management of preterm labor by tocolysis remains an unmet medical need. Prostaglandins play a major role in regulation of uterine activity and in molecular mechanisms of human labor and parturition. There is some circumstantial evidence that prostaglandin F2α by action through the prostaglandin receptor subtype FP is effective in key events during labor uterine contraction, rupture of membranes and cervical dilation. This role of FP is briefly reviewed. In this study, we tested the hypothesis that an orally active and selective FP antagonist may arrest labor and delay parturition in animal models.Methods
We examined the effects of a small molecule selective antagonist of the FP receptor (AS604872) in inhibition of spontaneous uterine contraction in pregnant rat near term. We tested AS604872 for its ability to delay preterm birth in a mouse model in which the anti-progestin agent RU486 triggered parturition.Results
By oral or intravenous dosing AS604872 reduced markedly and dose-dependently the spontaneous uterine contractions in late-term pregnant rats at gestational days 19–21. In pregnant mice, AS604872 delayed the preterm birth caused by RU486 administration. The effect was dose-dependent with a significant increase in the mean delivery time of 16 and 33 hours at oral doses of 30 mg/kg and 100 mg/kg, respectively, in the case of labor triggered at gestational day 14. In both models AS604872 appeared more effective than the β-agonist ritodrine.Conclusion
The tocolytic activity displayed by a selective FP receptor antagonist supports a key role for the FP receptor in the pathophysiology of premature birth and demonstrates the therapeutic potential of an FP antagonist for the treatment of preterm labor cases in which uterine hyperactivity plays a dominant role.995.
Reinheimer TM 《BMC pregnancy and childbirth》2007,7(Z1):S15
Background
Preterm labour (PTL) is a major cause of neonatal mortality and morbidity, and oxytocin (OT) antagonists are potential tocolytics. Atosiban (TRACTOCILE) is a mixed vasopressin V1A/OT antagonist registered for acute treatment of PTL in Europe. Other off-label drugs have serious side effects. Barusiban is a selective OT antagonist which has reached clinical development. A monkey model with OT-induced PTL was developed to compare barusiban and atosiban. In addition, the feasibility for long-term treatment of PTL with barusiban was explored.Methods
Conscious pregnant cynomolgus monkeys were monitored for intrauterine pressure (IUP). A sensor for IUP was implanted into the amniotic cavity, and biopotential sensors for electromyogram were attached to the uterus. For short-term experiments, individual low-dose OT infusions induced stable submaximal uterine contractions. Barusiban and atosiban were administered either as intravenous bolus or infusion at high or low doses. For long-term treatment, low-dose OT was infused daily for 3–6 hours to mimic PTL. In addition, continuous high-dose infusions of barusiban (150 μg kg-1 h-1) or fenoterol (3 μg kg-1 h-1) were administered.Results
Contractions of 15–40 mmHg were induced with individual OT infusions at 5–90 mU kg-1 h-1, and no OT-related desensitization occurred. Correlation was demonstrated between electromyograms and IUP curves. Barusiban was well tolerated and its potency was 4 times higher than atosiban's. Barusiban and atosiban demonstrated >95% efficacy. However, barusiban's duration of action was >13 hours (atosiban's 1–3 hours) and reversible with high-dose OT in emergency situations. OT control and fenoterol-treated monkeys delivered preterm (ca. day 154) and showed an increase in overall IUP. Barusiban-treated animals delivered normally following end of treatment (ca. day 163).Conclusion
The presented telemetry model provides an excellent method to evaluate PTL drug candidates. OT induced stable repetitive contractions and no desensitisation. Barusiban and atosiban demonstrated high efficacy and rapid onset of action. Barusiban, a selective OT antagonist has higher potency and prolonged duration of action than atosiban. Barusiban effectively suppressed IUP during daily OT-challenges, delayed labour, and prolonged monkeys' pregnancy till term.996.
Bardou M Rouget C Breuiller-Fouché M Loustalot C Naline E Sagot P Frydman R Morcillo EJ Advenier C Leroy MJ Morrison JJ 《BMC pregnancy and childbirth》2007,7(Z1):S14
The management of premature birth still remains unsatisfactory. Since the relative lack of efficiency and/or safety of current tocolytic agents have been highlighted, it is necessary to develop new uterorelaxant drugs deprived of important maternal and foetal side effects. Our work reported in this review focuses on a potential new target for tocolytic drugs, the beta3-adrenoceptor (ADRB3). This third type of ADRB is shown to be present and functional in human myometrium. We demonstrated that ADRB3 agonists are able to inhibit in-vitro spontaneous contractions of myometrial strips, via a cyclic AMP-mediated pathway. Furthermore, we established that ADRB3 is the predominant subtype over the ADRB2 in human myometrium and that its expression is increased in near-term myometrium, compared to non-pregnant myometrium. Finally, we reported that contrary to ADRB2, the human myometrial ADRB3 is resistant to long-term agonist-induced desensitisation. These compelling data confirm the clinical potential interest of ADRB3 agonists in the pharmacological management of preterm labour. 相似文献
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