Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Fetal Viability”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 127 records · Page 7Linked to original sources
PubMed1986

Chorionic villus sampling in continuing pregnancies. I. Low fetal loss rates in initial 109 cases.

Among the first 150 women who agreed to have chorionic villus sampling after receiving counseling and giving informed consent, 41 proved ineligible. In six (5.5%) of the remaining 109 cases in which chorionic villus sampling was performed, we were unsuccessful in obtaining an adequate amount of villi to permit diagnostic testing. In the single loss, fetal viability was confirmed 2 weeks after sampling; however, fetal death became evident 3 weeks later. In four (3.7%) cases the pregnancies were terminated because of abnormal results, and in one (0.9%) case the pregnancy was electively terminated after normal results. Among the 41 completed pregnancies no anomalies were evident in the infants. There were two premature deliveries; one of these two infants died shortly after birth following premature rupture of the membranes at 29 weeks' gestation. All undelivered cases were progressing normally at the time of submission.

Abortion, Induced↗
PubMed1991

Obstetrical management of patients with diabetes in pregnancy.

The management of the woman with diabetes diagnosed before the onset of pregnancy, or who develops it during pregnancy, requires a team approach involving the woman and her partner, the diabetes nurse educator, the dietitian, the endocrinologist, the obstetrician, the ultrasonologist and the paediatrician. It should start before pregnancy so that normoglycaemia is achieved before conception and maintained throughout gestation and labour. Fetoplacental surveillance commences with an early ultrasound to confirm fetal viability, repeated around 20 weeks to exclude major fetal malformations and then later in the third trimester to monitor fetal growth. CTG and biophysical profile assessment are major adjuncts to ensuring fetal well-being. The pregnancy should be allowed to go to full term when maternal blood glucose control has been satisfactory, fetal growth is within the normal range and other obstetrical complications, e.g. pre-eclampsia, are absent. Such an approach will ensure that the caesarean section rate can be minimized. During labour, the progress of labour and fetal well-being should be closely monitored. The woman who has microvascular complications of her diabetes (including proliferative retinopathy and nephropathy) requires even closer surveillance and premature delivery is more likely to be needed. The principles of management of the woman who develops gestational diabetes are similar, with even greater emphasis being placed on not inducing labour before full term unless complications dictate otherwise.

Delivery, Obstetric↗
PubMed1997

Perception of information, expectations and experiences among women and their partners attending a second-trimester routine ultrasound scan.

The aim of this study was to evaluate pre-scan counselling and the provision of information to parents-to-be, and their expectations before and experiences of a second trimester routine ultrasound scan. In the study, 303 pregnant women and their partners were asked to complete questionnaires before and after the scan. The main purposes of the examination were: dating, ascertaining fetal viability, and detection of multiple gestations. Although scanning for fetal malformations was not the purpose of the examination, 89% of the women and 84% of the men were concerned about this aspect. Even though it has been postulated that more women would not attend the examination if they knew it was for prenatal diagnostic purposes, the results of this study did not support this assumption. Only 57% of the women had received information at their antenatal care centers. A total of 88% of the women and 85% of the men said that they obtained sufficient information at the scan. Anxiety was low before the scan, both among women and men, with the exception of those women who had experienced problems at earlier scans. Positive feelings dominated during the scan and these feelings remained when experiences of the scan were reported by the parents-to-be after they had gone home. It is concluded that a routine second-trimester scan is a positive event for the majority of the participating women and men. In spite of this, we believe that certain measures should be taken to improve pre-scan counselling and the provision of adequate information.

Adult↗
PubMed2002

Contemporary trends in the management of delivery at 23 weeks' gestation.

The objective of this study is to investigate the current understanding of neonatal survival and the willingness to provide aggressive obstetric intervention at the limit of fetal viability among practicing perinatologists in the United States. A pretested survey was mailed to members of the Society for Maternal Fetal Medicine. The survey identified the practitioner's opinion of the lowest limit of viability and gestational ages at which antenatal steroids and cesarean section would first be provided. We also attempted to identify practitioner knowledge of survival at 23 and 24 weeks' gestation and years of perinatal practice. Of the 1244 surveys mailed to members of the Society for Maternal-Fetal Medicine practicing in the United States, 462 practitioners replied for a 37% response rate. Fifty percent considered the lower limit of viability to be 24 weeks' and 44.3% believed the lower limit of viability to be 23 weeks' gestation. Among respondents, the majority estimated a 0 to 10% survival rate at 23 weeks' and 25 to 50% survival rate at 24 weeks. Only 13% of respondents correctly estimates survival at 23 weeks' gestation as >25%, and only 17% correctly estimated survival at 24 weeks' at >50%. Among practitioners, 43.6% would first give antenatal steroids after 24 weeks' gestation but 55.6%would administer steroids before the beginning of week 24. Twenty-eight percent would routinely monitor a fetus less than 24 weeks' gestation. Consistent with this observation, 21% would perform a cesarean section before 24 weeks' gestation. We find that respondents underestimate the consensus in the most recent literature on survival of infants born at 23 to 24 weeks. This underestimation may lead to a limitation in interventions offered.

Attitude of Health Personnel↗
PubMed1990

Carbendazim-induced alterations of reproductive development and function in the rat and hamster.

We are developing a data base that will allow us to select endpoints that would be useful in the detection of reproductive toxicity in a multigenerational test. In this effort, carbendazim (MBC), a known reproductive toxicant, was administered to male and female rats from weaning, through puberty, gestation, and lactation. A similar study was conducted with hamsters. In rats, MBC was administered at 0, 50, 100, 200, or 400 mg/kg/day. Hamsters were dosed at 0 or 400 mg/kg/day. In the parent (P0) generation, landmarks of puberty were measured. In females, estrous cyclicity, litter size, the number of implants, organ weights, and histology were assessed. Our assessment of the male rat included organ weights, testicular and epididymal sperm counts, a quantitative measure of sperm motility, sperm morphology, testicular histology, and endocrine measures. The growth, viability, and reproductive function of the offspring (F1) were observed during a 4-month period of continuous breeding. In the P0 of both species. MBC did not alter pubertal development, growth, or viability. The reproductive potential of the rats treated with MBC at 200 and 400 mg/kg/day was reduced due to effects on sperm production and fetal viability. In the male rat, MBC treatment markedly altered sperm morphology, testicular and epididymal weights, and sperm numbers and testicular histology. Fertility, sperm motility, and hormonal levels were altered, primarily in the males with very low sperm counts. The ability to conceive did not appear to involve a female factor. In P0 female rats, MBC administration caused postimplantation losses in the high-dosage groups and a few malformed rat pups were found in the litters from the 100 and 200 treatment groups. MBC was less toxic to the hamster than the rat. The only reproductive effects induced by MBC treatment were on sperm measures. Fertility of the P0 generation and fetal and neonatal (F1) viability were not decreased by MBC administration. In the male rat, testis weight, sperm numbers in the cauda epididymis and testis and sperm morphology were sensitive to the effects of MBC. In females, counting implantation scars at necropsy was useful, as this information allowed us to confirm pregnancy and identify postimplantation losses induced by MBC administration.

Animals↗
PubMed2006

Early pregnancy diagnosis by palpation per rectum: influence on embryo/fetal viability in dairy cattle.

The objective was to estimate the effect of palpation per rectum (for early pregnancy diagnosis) on embryo/fetal viability in dairy cattle. A controlled, randomized block-design experiment with two blocks, one by category, and the other by number of embryos, was conducted. Five-hundred-and-twenty pregnant dairy cows and heifers with a viable embryo detected by transrectal ultrasonography (TRUS) between days 29 and 32 after AI were included. The pregnant females were randomly allocated into two nearly equal groups: palpation per rectum (PAL group; n=258) and no palpation per rectum (NPAL group; n=262). The PAL group was submitted to palpation per rectum (PPR) using the fetal membrane slip (FMS) technique once between days 34 and 41 of pregnancy. The fetal membrane slip consisted of compressing the pregnant uterine horn and allowing the chorioallantoic membrane to slip between the fingers. Both groups were submitted to two additional TRUS at days 45 and 60 of pregnancy, to monitor the potential immediate and delayed deleterious effects of PPR on embryo and fetal viability, respectively. A diagnosis of embryo/fetal death was made when there was no embryo/fetal heart beat or the absence of positive signs of pregnancy in an animal previously diagnosed pregnant, or the presence of signs of embryo/fetal degeneration. The overall rate of embryo/fetal death was 14.0% (73/520). Embryonic death (10%; 52/520) was higher than fetal death (4.5%; 21/468; P<0.001). Embryo/fetal mortality was higher in cows (16.4%; 59/360) than in heifers (8.8%; 14/160; P<0.025) and in cattle with twin (25.5%; 12/47) versus singleton pregnancies (12.9%; 61/473; P<0.025), but was not different (P>0.05) between PAL (14.7%; 38/258) and NPAL (13.4%; 35/262). In conclusion, PPR between days 34 and 41 of pregnancy using the fetal membrane slip technique did not affect embryo/fetal viability.

Animals↗
PubMed1980

Dept. of Pharmacology & Toxicology, University of Rochester, School of Medicine and Dentistry, New York.

Fetal death in rats was produced by subcutaneous injections of CdCl2 (40 mumoles/kg) on day 18 of pregnancy. The incidence of fetal death following these maternal injections was 74.9%, with mean (+/- SD) fetal cadmium burdens of 8.6 +/- 4.4 nmoles. To separate maternal from fetal effects of cadmium, doses of CdCl2 up to 60 mumoles/kg fetal weight were injected directly into fetuses on day 18 of gestation. Fetal viability was then determined on gestational day 21. Following direct fetal injection, mean fetal body burdens of cadmium were 74.6 +/- 34.8 nmoles, but the incidence of fetal dealth was only 11.5%. The high incidence of fetal death following maternal exposure to CdCl2 is not solely explained by the direct effects of CdCl2 on the fetus. Thus, the fetal toxicity of cadmium may be the result of some extra-fetal mechanism such as maternal toxicity or the observed placental necrosis.

Animals↗
PubMed1990

Operative techniques in the fetal rabbit.

The development of fetal surgical techniques has made the antenatal correction of congenital defects possible. These techniques have evolved from trials with animal models, permitting increasingly sophisticated operations with low morbidity and mortality. Experimental models range from large animals offering longer gestations but with single pregnancies and high cost, to smaller animals offering multiple pregnancies at reduced cost but with shorter gestations. This paper describes operative techniques in the fetal rabbit and its advantages as a fetal surgical model. Experience with the pregnant rabbit has shown it to be a suitable surgical model for several reasons. Pregnancies are multiple, increasing cost effectiveness and permitting operation on up to eight fetuses per litter without fetal loss. Techniques that promote fetal survival include local housing of does several days prior to operation and preoperative sedation. Spontaneous mask ventilation provides ease of anesthetic administration and titration. Overall surgery is well tolerated with a low incidence of intraoperative complications. Rabbit models have been used in the study of transamniotic fetal feeding, abdominal wall defects, and wound healing. These techniques have resulted in postoperative fetal viability approaching 90%, with negligible maternal mortality in over 4000 fetal operations, thereby making the rabbit a manageable cost-effective model of fetal surgery.

Animals↗
PubMed1988

Expectant management of abdominal pregnancy. A report of two cases.

In two recent consecutive cases of abdominal pregnancy the diagnosis was made at 18 weeks' gestation, and the patients refused immediate surgery and elected to maintain the pregnancy until fetal viability developed. Both patients were managed expectantly with continuous antepartum hospitalization. Fetal assessment was by serial ultrasound assessment of growth and amniotic fluid volume and by nonstress testing. Planned operative delivery was accomplished at 28 1/2 weeks and 33 weeks' gestation. In the second case the diagnosis was confirmed by magnetic resonance imaging. That fetus was also assessed with umbilical artery Doppler flow studies. Despite significant morbidity, both the mothers and infants are alive and well.

Adult↗
PubMedDate not supplied

DNA adducts in human and patas monkey maternal and fetal tissues induced by platinum drug chemotherapy.

Platinum-DNA adducts in placenta and blood from a woman exposed to 200 mg/m2 of cis-diamminedichloroplatinum(II) (cisplatin) and 300 mg/m2 diamminecyclobutanedicarboxylatoplatinum(II) (carboplatin) for ovarian cancer have been documented by cisplatin-DNA enzyme-linked immunosorbent assay (ELISA) and atomic absorbance spectrometry (AAS). A patas monkey model was used to investigate transplacentally induced cisplatin-DNA damage in fetal tissues. During the last trimester of gestation, 5 patas monkeys were given multiple doses of cisplatin to mimic human ovarian cancer treatment. In spite of careful choice of dose and treatment conditions, cumulative toxicity occurred in monkeys given doses comparable on a mg/m2 basis to those received by the human. A total dose of 12 mg/m2 (0.625 mg/kg body weight), given in the last trimester, supported fetal viability, and multiple tissues, taken by cesarean section, were examined in the fetal monkeys. By cisplatin-DNA ELISA and AAS, maternal tissues from the monkey receiving the highest dose contained approximately twice as much DNA damage as the fetal tissues. A similar relationship was observed when we compared DNA adduct formation in fetal liver and biopsies of liver taken from the monkey dams at cesarean delivery. In all of the monkey pairs studied there were very significant levels of DNA damage in the placenta, and high adduct levels in brains of fetuses that survived treatment. Thus, cisplatin does cross the placenta in the patas monkey. These observations imply that the human fetus, for which the total maternal dose was approximately 5.4 mg platinum drug/kg body weight, may also have sustained some DNA damage.

Adult↗
PubMed2004

Obstetric complications of twin pregnancies.

Advances in assisted reproductive technology and increases in the proportion of maternities in older women have both contributed to the steep increase in the incidence of twin pregnancies since the 1980s. Maternal and perinatal complications are higher in twins than in singleton pregnancies. A significant proportion of perinatal mortality and morbidity among twins is due to the high incidence of preterm delivery and the added complication of twin-to-twin transfusion syndrome (TTTS) in monochorionic twins. Monochorionic twins also have a much higher rate of perinatal mortality than dichorionic twins, the greatest risk being before fetal viability (<24 weeks gestation). Early diagnosis of twins and their chorionicity, close fetal surveillance, particularly of monochorionic twins, and prompt therapeutic intervention in TTS are necessary to reduce perinatal mortality. Intrapartum management in the hospital setting with anaesthetic and neonatal facilities, as well as critical assessment of mode of delivery, have led to better outcomes. Ultrasonography is a valuable tool in the management of twin pregnancy. This chapter briefly summarises these topics, with a particular focus on recent literature.

Chromosome Aberrations↗
PubMed1993

Reference ranges and ultrasonographic exposure conditions for pulsed Doppler sonographic studies of the fetal internal carotid artery.

We describe the 5th to 95th percentiles for the resistive index from the fetal internal carotid artery and measurements of (1) scanning time and (2) axial distance between transducer face and the fetal skull during pulsed Doppler examinations. Cerebral resistance peaks at 30 weeks' gestation and declines thereafter. The median duration of pulsed Doppler exposure was 31 seconds (range, 4-80 seconds), and the median transducer-skull distance was 2.2 cm (range, 1.3-6.2 cm). Our data provide reference ranges covering the entire period of fetal viability and help define ultrasonographic exposure conditions during pulsed Doppler examinations of fetal intracranial vessels.

Carotid Artery, Internal↗
PubMed1999

[Intrauterine death in twin pregnancies].

The loss of a fetus in a multiple pregnancy is relatively frequent. The main risk factor is a monochorionic twin pregnancy. If fetal loss occurs after 16 weeks of pregnancy, the survivor is also at increased risk of intrauterine death. In monochorionic twins, the risk of neurological sequelae can be as high as 25%. These lesions are due to acute episodes of hypoperfusion immediately following the death of the co-twin. Maternal complications including coagulation disorders are rare. The management will vary according to the type of placenta, the gestational age and the condition of the surviving twin. When the last trimenon has been reached, rapid delivery is probably the safest management. In monochorinoic biamniotic twins, the risk to the survivor often justifies the induction of delivery between 28 and 32 weeks of gestation after steroids have been administered. In most cases, before the 28th week of gestation, a conservative management will be proposed. In monochorionic monoamniotic twins, immediate delivery should be considered as soon as fetal viability is reached.

Female↗
PubMed1993

[Gynecologic cancers and pregnancy. With the exception of breast cancer].

Pregnancy should be a privileged opportunity to detect the two gynecologic cancers which occur most frequently during this period (breast cancer excepted). Their detection during pregnancy doesn't influence the maternal prognosis on condition that an ideal therapeutic protocol is applied. The embryonic and fetal toxicity of anticancerous treatments is known to justify medical pregnancy interruption in some cases, and in others allow their utilization looking forward to fetal viability.

Embryonic and Fetal Development↗
PubMed2006

Reproductive and developmental toxicity of inhaled 2,3-dichloro-1,3-butadiene in rats.

Inhalation developmental and reproductive toxicity studies were conducted with 2,3-dichloro-1,3-butadiene (DCBD), a monomer used in the production of synthetic rubber. In the reproductive toxicity study, Crl:CD(SD)IGS BR rats (24/sex/group) were exposed whole body by inhalation to 0, 1, 5, or 50 ppm DCBD (6 h/day) for approximately 10-11 weeks total, through premating (8 weeks; 5 days/week), cohabitation of mating pairs (up to 2 weeks, 7 days/week), post-cohabitation for males (approximately 7 days) and from conception to implantation (gestation days 0-7 [GD 0-7]), followed by a recovery period (GD 8-21) for presumed pregnant females. Estrous cyclicity was evaluated during premating (last 3 weeks) and cohabitation. Reproductive organs and potential target organs, sperm parameters, and GD 21 fetuses (viability, weight, external alterations) were evaluated. In the developmental study, pregnant Crl:CD(SD)IGS BR rats (22/group) were exposed whole body by inhalation to 0, 1, 10, or 50 ppm DCBD (6 h/day) on GD 6-20; dams were necropsied on GD 21 (gross post-mortem only) and fetuses were evaluated (viability, weight, and external, visceral and skeletal exams). During the in-life portion of the studies, body weight, food consumption, and clinical observation data were collected. At 50 ppm, gasping and labored breathing occurred in both studies during the first few exposures; body weight and food consumption parameters were affected in parental animals from both studies, but were more severely affected in the developmental study. Fetal weight was decreased in the developmental study at 50 ppm. Degeneration of the nasal olfactory epithelium was observed in the reproduction study at 50 ppm. There were no effects on reproductive function, embryo-fetal viability, or increases in fetal structural alterations in either study. The no-observed-adverse-effect level (NOAEL) for reproductive toxicity was 50 ppm. The NOAEL for systemic toxicity in the reproduction study was 5 ppm based on adverse effects on body weight and food consumption parameters and nasal olfactory epithelial toxicity at 50 ppm in parental rats. The NOAEL for maternal and developmental toxicity was 10 ppm based on reduced maternal weight gain and food consumption and reduced fetal weight at 50 ppm in the developmental toxicity study.

Administration, Inhalation↗
PubMed1985

Intrapartum fetal heart rate monitoring of the extremely premature fetus.

When cesarean section is not warranted because of extreme prematurity, continuous electronic fetal heart rate monitoring during the intrapartum period and in utero resuscitation of the distressed fetus are indicated, especially in cases of borderline fetal viability. Two cases are presented to illustrate the benefit of such measures when fetal distress occurs and the fetus is judged to be too small for operative intervention.

Adult↗
PubMed1989

Developmental toxicity of perfluorodecanoic acid in C57BL/6N mice.

Perfluorodecanoic acid (PFDA) is a representative of the perfluorinated carboxylic acids used as commercial wetting agents and flame retardants. Signs of PFDA toxicity have been reported to resemble those seen after exposure to TCDD. To determine if PFDA exhibits teratogenic effects similar to those of TCDD or is a developmental toxin, time-mated C57BL/6N mice were administered PFDA by gavage in corn oil (10 ml/kg) on gestation days (gd) 10-13 or gd 6-15 at levels of 0, 0.25, 0.5, 1.0, 2.0, 4.0, 8.0, 16.0, or 32.0 mg/kg/day or 0, 0.03, 0.3, 1.0, 3.0, 6.4, or 12.8 mg/kg/day, respectively. Dams were killed on gd 18 and maternal and fetal toxicity was assessed. Fetuses were examined for external, visceral, or skeletal malformations. Maternal body weight gain (corrected for the weight of the gravid uterus) was significantly reduced as a result of PFDA treatment at 6.4 and 12.8 mg/kg/day (gd 6-15) and 16.0 and 32.0 mg/kg/day (gd 10-13). Fetal viability was decreased only in those groups showing extensive maternal body weight loss. Fetal body weights were significantly reduced at levels as low as 0.1 mg/kg/day (gd 6-15) and 0.5 mg/kg/day (gd 10-13). No hydronephrosis, cleft palate, or edema was observed nor were any other soft tissue or skeletal malformations detected. Thus, PFDA does not produce malformations in C57BL/6N mice, and the developmental toxicity observed (increased fetal mortality and decreased live fetal body weight) was seen only at doses that were maternally toxic.

Animals↗
PubMed1981

High plasma zinc levels following oral dosing in rats and the incorporation of 3H-thymidine into deoxyribonucleic acid in rat fetuses.

In fasted rats, a single oral dose of zinc, equivalent to the total daily zinc intake, caused plasma zinc levels to rise about five-fold 1.5 h after treatment. Higher values were obtained following higher dose levels. At maternal plasma zinc levels approximately 10-fold above normal, fetal viability was disturbed and incorporation of 3H-thymidine into DNA became impaired in fetal (20-d) rat brain and liver tissue.

Animals↗