Showing papers on "Pregnancy published in 1993"
TL;DR: This paper shows how fetal undernutrition at different stages of gestation can be linked to these patterns of early growth in babies who are small at birth or during infancy.
2,594 citations
TL;DR: It is argued that the increasing incidence of reproductive abnormalities in the human male may be related to increased oestrogen exposure in utero, and mechanisms by which this exposure could occur are identified.
1,848 citations
TL;DR: More research is needed into the etiologic roles of menstrual cycle characteristics, especially research examining the probability of prolonged exposure to both estrogens and progesterone concurrently.
Abstract: PIP: Early age at menarche, late age at menopause, and late age at first full-term pregnancy are linked to a modest increase in the risk of developing breast cancer. Some evidence suggests that the earlier the full-term pregnancy, the earlier the period of decreased susceptibility of breast tissue changes begins. Nulliparity is related to an increased risk for breast cancer diagnosed after 40 years old. Multiple full-term pregnancies decrease the risk of breast cancers diagnosed after 40 years regardless of the age at first birth. On the other hand, they may increase the risk for breast cancers diagnosed before 40 years old. Surgical removal of the ovaries protects against breast cancer. Breast feeding apparently protects against breast cancer in China, but a protective effect has not been established in the US. Other than shorter intervals between menstrual periods, which tend to increase the risk, research has not yet made clear the etiologic roles of menstrual cycle characteristics. Other unclear etiologic roles include increased intervals between births, spontaneous and induced abortion, infertility, multiple births at last pregnancy, and hypertension during pregnancy. Researchers tend to accept a mechanism to explain the epidemiologic characteristics of menstrual activity and the increased risk of breast cancer, but no mechanisms have emerged for the other likely risk factors. Greater exposure to estrogen and progesterone simultaneously are linked to early age at menarche, late age at menopause, and shorter menstrual cycle length. So far, data show that long-term combined estrogen/progestin hormone replacement therapy and long-term use of oral contraceptives increase the risk of breast cancer. Moderately increased risks linked to longterm estrogen replacement therapy and obesity in postmenopausal women indicate that estrogen alone influences breast cancer risk. Since much of the research on breast cancer risk factors are inconclusive, more research is needed, especially research examining the probability of prolonged exposure to both estrogens and progesterone concurrently.
1,417 citations
1,221 citations
TL;DR: The placenta is able to release hormones and other substances directly into the maternal circulation as discussed by the authors, which can be interpreted as an attempt by a poorly nourished fetus to increase its supply of nutrients by increasing the resistance of its mother's peripheral circulation.
Abstract: Pregnancy has commonly been viewed as a cooperative interaction between a mother and her fetus. The effects of natural selection on genes expressed in fetuses, however, may be opposed by the effects of natural selection on genes expressed in mothers. In this sense, a genetic conflict can be said to exist between maternal and fetal genes. Fetal genes will be selected to increase the transfer of nutrients to their fetus, and maternal genes will be selected to limit transfers in excess of some maternal optimum. Thus a process of evolutionary escalation is predicted in which fetal actions are opposed by maternal countermeasures. The phenomenon of genomic imprinting means that a similar conflict exists within fetal cells between genes that are expressed when maternally derived, and genes that are expressed when paternally derived. During implantation, fetally derived cells (trophoblast) invade the maternal endometrium and remodel the endometrial spiral arteries into low-resistance vessels that are unable to constrict. This invasion has three consequences. First, the fetus gains direct access to its mother's arterial blood. Therefore, a mother cannot reduce the nutrient content of blood reaching the placenta without reducing the nutrient supply to her own tissues. Second, the volume of blood reaching the placenta becomes largely independent of control by the local maternal vasculature. Third, the placenta is able to release hormones and other substances directly into the maternal circulation. Placental hormones, including human chorionic gonadotropin (hCG) and human placental lactogen (hPL), are predicted to manipulate maternal physiology for fetal benefit. For example, hPL is proposed to act on maternal prolactin receptors to increase maternal resistance to insulin. If unopposed, the effect of hPL would be to maintain higher blood glucose levels for longer periods after meals. This action, however, is countered by increased maternal production of insulin. Gestational diabetes develops if the mother is unable to mount an adequate response to fetal manipulation. Similarly, fetal genes are predicted to enhance the flow of maternal blood through the placenta by increasing maternal blood pressure. Preeclampsia can be interpreted as an attempt by a poorly nourished fetus to increase its supply of nutrients by increasing the resistance of its mother's peripheral circulation.
1,041 citations
TL;DR: It was found that rat placental 11 beta-OHSD activity correlated positively with term fetal weight and negatively with placental weight, and offspring of rats treated during pregnancy with dexamethasone had lower birthweights and higher blood pressure when adult than did offspring of control rats.
868 citations
TL;DR: Independent of biomedical risk, maternal prenatal stress factors are significantly associated with infant birth weight and with gestational age at birth.
772 citations
770 citations
TL;DR: A randomized, controlled trial of periconceptional multivitamin supplementation to test the efficacy of this treatment in reducing the incidence of a first occurrence of neural-tube defects.
Abstract: Background. The risk of recurrent neural-tube defects is decreased in women who take folic acid or multivitamins containing folic acid during the periconceptional period. The extent to which such supplementation can reduce the first occurrence of defects is not known. Methods. We conducted a randomized, controlled trial of periconceptional multivitamin supplementation to test the efficacy of this treatment in reducing the incidence of a first occurrence of neural-tube defects. Women planning a pregnancy (in most cases their first) were randomly assigned to receive a single tablet of a vitamin supplement (containing 12 vitamins, including 0.8 mg of folic acid; 4 minerals; and 3 trace elements) or a trace-element supplement (containing copper, manganese, zinc, and a very low dose of vitamin C) daily for at least one month before conception and until the date of the second missed menstrual period or later. Results. Pregnancy was confirmed in 4753 women. The outcome of the pregnancy (whether the fetu...
673 citations
TL;DR: In this paper, the effects of prenatal social support on maternal and infant health and well-being in a sample of low-income pregnant women (N = 129) were examined, and three aspects of support (amount received, quality of support received, and network resources) and four outcomes were studied.
Abstract: This prospective study examined the effects of prenatal social support on maternal and infant health and well-being in a sample of low-income pregnant women (N = 129). Three aspects of support (amount received, quality of support received, and network resources) and four outcomes (birth weight, Apgar scores, labor progress, and postpartum depression) were studied. Results indicated that women who received more support had better labor progress and babies with higher Apgar scores. Women with higher quality support had babies with higher Apgar scores and experienced less postpartum depression. Also, women with larger networks had babies of higher birth weight. Further analyses indicated that the outcomes as a whole were more consistently predicted by instrumental rather than emotional forms of support. Finally, although there was some evidence for stress-buffering effects of support, the overall findings were more consistent with a main effect model.
642 citations
TL;DR: Repeated prenatal ultrasound imaging and Doppler flow examinations should be restricted to those women to whom the information is likely to be of clinical benefit.
TL;DR: A randomized trial involving 15,151 pregnant women at low risk for perinatal problems to determine whether ultrasound screening decreased the frequency of adversePerinatal outcomes.
Abstract: Background Many clinicians advocate routine ultrasound screening during pregnancy to detect congenital anomalies, multiple-gestation pregnancies, fetal growth disorders, placental abnormalities, and errors in the estimation of gestational age. However, it is not known whether the detection of these conditions through screening leads to interventions that improve perinatal outcome. Methods We conducted a randomized trial involving 15,151 pregnant women at low risk for perinatal problems to determine whether ultrasound screening decreased the frequency of adverse perinatal outcomes. The women randomly assigned to the ultrasound-screening group underwent one sonographic examination at 15 to 22 weeks of gestation and another at 31 to 35 weeks. The women in the control group underwent ultrasonography only for medical indications, as identified by their physicians. Adverse perinatal outcome was defined as fetal death, neonatal death, or neonatal morbidity such as intraventricular hemorrhage. Results The mean nu...
TL;DR: Increasing waist-hip ratio is negatively associated with the probability of conception per cycle, before and after adjustment for confounding factors.
Abstract: OBJECTIVES--To study the effect of body fat distribution in women of reproductive age on fecundity. DESIGN--Prospective cohort study of all women who had entered a donor insemination programme. SETTING--One fertility clinic serving a large part of the midwest of the Netherlands. SUBJECTS--Of 542 women attending the clinic for artificial insemination for the first time, 500 women were eligible for study. MAIN OUTCOME MEASURES--Probability of conception per cycle and number of insemination cycles before pregnancy or stopping treatment. RESULTS--A 0.1 unit increase in waist-hip ratio led to a 30% decrease in probability of conception per cycle (hazard ratio 0.706; 95% confidence interval 0.562 to 0.887) after adjustment for age, fatness, reasons for artificial insemination, cycle length and regularity, smoking, and parity. Increasing age was significantly related to lower fecundity (p < 0.05); very lean and obese women were less likely to conceive (p < 0.10) as were women with subfertile partners (p < 0.10). All other exposure variables were not significantly related to fecundity. CONCLUSIONS--Increasing waist-hip ratio is negatively associated with the probability of conception per cycle, before and after adjustment for confounding factors. Body fat distribution in women of reproductive age seems to have more impact on fertility than age or obesity.
TL;DR: A dose-response relation between psychological distress in the 30th week of pregnancy and risk of pre term delivery was found, but distress measured in the 16th week was not related to preterm delivery.
Abstract: OBJECTIVE--To investigate if psychological distress during pregnancy is associated with increased risk of preterm delivery. DESIGN--Prospective, population based, follow up study with repeated measures of psychological distress (general health questionnaire), based on the use of questionnaires. SETTING--Antenatal care clinic and delivery ward, Aarhus University Hospital, Denmark. SUBJECTS--8719 women with singleton pregnancies attending antenatal care for the initial visit between 1 August 1989 and 30 September 1991; 5872 women (67%) completed all questionnaires. MAIN OUTCOME MEASURE--Preterm delivery. Estimation of gestational age at delivery was mainly based on early ultrasound measurements. RESULTS--In 197 cases (3.6%) the woman delivered prematurely (less than 259 days). A dose-response relation between psychological distress in the 30th week of pregnancy and risk of preterm delivery was found, but distress measured in the 16th week was not related to preterm delivery. Control of confounding was secured by the use of multivariate logistic regression models. Relative risk for preterm delivery was 1.22 (95% confidence interval 0.84 to 1.79) for moderate distress and 1.75 (1.20 to 2.54) for high distress in comparison to low distress. CONCLUSIONS--Psychological distress later in pregnancy is associated with an increased risk of preterm delivery. Future interventional studies should focus on ways of lowering psychological distress in late pregnancy.
TL;DR: Data support the concept that maternal hemodynamic adaptation to pregnancy is most likely triggered by a primary fall in systemic vascular tone, which develops because the vascular filling state normalizes, whereas the reduced afterload reduction is maintained.
TL;DR: Cerebral venous thrombosis associated with pregnancy and puerperium has a more acute onset and a better prognosis than thromBosis due to other causes and these findings might be helpful in the diagnostic and therapeutic strategies for patients with cerebral venousThrombotic disease.
Abstract: Cerebral venous thrombosis is characterized by its clinical pleomorphism and pathogenetic variability We studied 67 patients with cerebral venous thrombosis associated with pregnancy and puerperium and compared them with 46 other cases unrelated to obstetric causes to disclose differences in their clinical presentation, neuroradiological findings, clinical course, and prognosisIn this retrospective study, we analyzed the clinical, laboratory, and neuroimaging findings of 113 patients collected consecutively at our institute The diagnosis of cerebral venous thrombosis was confirmed by angiography, magnetic resonance imaging, or neuropathological studyPatients with cerebral venous thrombosis associated with pregnancy and puerperium were younger (average age, 26 versus 36 years), and in most, the onset of symptoms was acute (82% versus 54%; P = 003) The evolution of symptoms reached a plateau within 10 days in 70% of patients with thrombosis from obstetric causes, compared with only 45% in those from o
TL;DR: Bovine embryos become more resistant to adverse effects of maternal heat stress as pregnancy progresses; substantial resistance develops by d 3.
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TL;DR: The symptoms of nausea and vomiting in pregnancy were described by 363 pregnant women who kept daily symptom diaries, finding that 80% of women had symptoms, 28% experienced nausea only, while 52% had nausea and vomit.
Abstract: The symptoms of nausea and vomiting in pregnancy were described by 363 pregnant women who kept daily symptom diaries. All delivered a single live baby. The majority of information collected was prospective, with the median day from last menstrual period to initial interview by the study midwife being day 57. It was found that 80% of women had symptoms, 28% experienced nausea only, while 52% had nausea and vomiting. The mean number of days from last menstrual period to onset and cessation of symptoms was 39 and 84, respectively, and 40% of women's symptoms ended abruptly. Cessation of symptoms occurred at approximately the same day from the last menstrual period whether they had begun early or later, severely or mildly [corrected]. The median total number of hours of nausea per pregnancy in those 292 women experiencing symptoms was 56, with peak symptoms occurring in the ninth week. Eighty five per cent of women experienced days with two episodes of nausea. Fifty three per cent of episodes of vomiting occurred between 06.00 hours and 12.00 hours. The symptom complex can be defined as episodic daytime pregnancy sickness. Among the study population, 206 women were in paid employment. Seventy three of these women (35%) spent a mean of 62 hours away from their paid work because of symptoms of nausea and vomiting, showing the socioeconomic significance of this condition. The detailed information gathered should help in the investigation of the aetiology of nausea and vomiting during pregnancy.
TL;DR: This regimen requires minimal laboratory follow-up and eliminates leukovorin recovery, making it the regimen of choice for medical treatment of unruptured ectopic pregnancy.
TL;DR: It is suggested that the maternal immune response to paternal HLA antigens may have a role in the pregnancy-induced remission of rheumatoid arthritis.
Abstract: Background Rheumatoid arthritis frequently remits during pregnancy, for unknown reasons. Since an immune response to paternally inherited fetal HLA can occur during normal pregnancy and since rheumatoid arthritis is an autoimmune disorder with a known HLA class II antigen association, we tested the hypothesis that maternal-fetal disparity in HLA alloantigens might be associated with the pregnancy-induced remission of rheumatoid arthritis. Methods We studied 57 pregnancies of 41 women with rheumatoid arthritis, 18 prospectively and 39 retrospectively. Serologic and DNA techniques were used to study HLA class I and II antigens. For newborns, typing was performed from cord-blood samples obtained at delivery. For four young children, typing was performed from DNA extracted from hair samples. Results We found significantly more maternal-fetal disparity in HLA-DR and DQ antigens in pregnancies characterized by the remission or improvement of rheumatoid arthritis than in pregnancies characterized by active disea...
TL;DR: There were no significant differences between the two groups in birth weight, Apgar scores, cord-blood gas values, frequency of multiple gestation, or incidence of respiratory distress syndrom...
Abstract: Background The use of indomethacin as a tocolytic agent in pregnant women appears to be accompanied by a low incidence of neonatal complications. However, the neonatal effects of indomethacin have been studied primarily in infants born after 32 weeks' gestation. This study was designed to examine the incidence of neonatal complications in very premature infants. Methods We identified 57 infants delivered at or before 30 weeks' gestation whose mothers had been treated with indomethacin for preterm labor and matched them with 57 infants whose mothers had not received indomethacin. The infants in the two groups were matched for sex, gestational age at delivery (mean [±SD], 27.6 ±2.0 weeks), exposure to betamethasone for 24 hours or more before delivery, and rupture of membranes 24 hours or more before delivery. Results There were no significant differences between the two groups in birth weight, Apgar scores, cord-blood gas values, frequency of multiple gestation, or incidence of respiratory distress syndrom...
TL;DR: This study suggests that the use of fluoxetine during embryogenesis is not associated with an increased risk of major malformations, and suggests that long-term studies will be warranted to rule out potential developmental teratology of fluxetine, which affects a central nervous system neurotransmitter.
Abstract: Objective. —To compare pregnancy outcome following first-trimester fluoxetine (Prozac) exposure with pregnancy outcome in two matched control groups. Fluoxetine is a new antidepressant used by many young women. Currently, no published data exist on its safety in pregnancy. Design. —We prospectively collected and followed up 128 pregnant women exposed to a mean daily dose of 25.8 mg (±13 mg) of fluoxetine during the first trimester and compared pregnancy outcome with two matched groups of women exposed during the first trimester of pregnancy to either nonteratogens or tricyclic antidepressants. Results. —Rates of major malformations were comparable within the three groups and did not exceed those expected in the general population. Women treated with fluoxetine had a tendency for increased risk for miscarriage when compared with women exposed to nonteratogens (relative risk, 1.9; 95% confidence interval, 0.92 to 3.92). The rate of miscarriages in the fluoxetine group was comparable with the tricyclic group (13.5% and 12.2% vs 6.8% in the nonteratogens). Conclusions. —Our study suggests that the use of fluoxetine during embryogenesis is not associated with an increased risk of major malformations. Women exposed to both fluoxetine and tricyclic antidepressants tended to report higher rates of miscarriage; further studies will be needed to confirm this observation and to separate the effects of the psychiatric condition from the associated drugs. Long-term studies will be warranted to rule out potential developmental teratology of fluoxetine, which affects a central nervous system neurotransmitter. ( JAMA . 1993;269:2246-2248)
TL;DR: Periconceptional multivitamin supplementation can reduce not only the rate of neural tube defects but also the rateof other major non-genetic syndromatic congenital abnormalities.
Abstract: OBJECTIVE--To study the effect of periconceptional multivitamin supplementation on neural tube defects and other congenital abnormality entities. DESIGN--Randomised controlled trial of supplementation with multivitamins and trace elements. SETTING--Hungarian family planning programme. SUBJECTS--4156 pregnancies with known outcome and 3713 infants evaluated in the eighth month of life. INTERVENTIONS--A single tablet of a multivitamin including 0.8 mg of folic acid or trace elements supplement daily for at least one month before conception and at least two months after conception. MAIN OUTCOME MEASURES--Number of major and mild congenital abnormalities. RESULTS--The rate of all major congenital abnormalities was significantly lower in the group given vitamins than in the group given trace elements and this difference cannot be explained totally by the significant reduction of neural tube defects. The rate of major congenital abnormalities other than neural tube defects and genetic syndromes was 9.0/1000 in pregnancies with known outcome in the vitamin group and 16.6/1000 in the trace element group; relative risk 1.85 (95% confidence interval 1.02 to 3.38); difference, 7.6/1000. The rate of all major congenital abnormalities other than neural tube defects and genetic syndromes diagnosed up to the eighth month of life was 14.7/1000 informative pregnancies in the vitamin group and 28.3/1000 in the trace element group; relative risk 1.95 (1.23 to 3.09); difference, 13.6/1000. The rate of some congenital abnormalities was lower in the vitamin group than in the trace element group but the differences for each group of abnormalities were not significant. CONCLUSIONS--Periconceptional multivitamin supplementation can reduce not only the rate of neural tube defects but also the rate of other major non-genetic syndromatic congenital abnormalities. Further studies are needed to differentiate the chance effect and vitamin dependent effect.
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TL;DR: The large data base assembled for this analysis provides current, stable birth weight-gestational age percentiles for classifying newborns from a developed country as small, appropriate, or large for gestational age.
TL;DR: In this paper, the authors assessed the association between bacterial vaginosis in early pregnancy and adverse pregnancy outcome, including preterm labor, preterm birth, and preterm rupture of membranes (PROM).
TL;DR: It is possible to identify two subgroups of patients among those who are delivered preterm because of preterm labor or premature rupture of membranes, one with infection of the products of conception and another with maternal placental vasculopathy.
Journal Article•
TL;DR: Prenatal care should include a routine screening question about domestic violence, and identified patients should be appropriately counselled and referred.
Abstract: OBJECTIVES: To determine the prevalence of physical abuse during late pregnancy and to investigate how abused and nonabused pregnant women differ in demographic characteristics, health habits, psychologic distress and attitudes about fetal health. DESIGN: Survey of women attending for prenatal health care or admitted to hospital for delivery. The information was obtained on one occasion from self-report questionnaires, completed with the option of anonymity. SETTINGS: Community-based prenatal clinic, private obstetricians9 offices in a large city, private family physicians9 offices in a large city, family physicians9 offices in a small town, and a university teaching hospital. PATIENTS: English-speaking women at 20 weeks9 or more gestation attending or admitted consecutively. INTERVENTIONS: Three self-report questionnaires: the General Health Questionnaire (GHQ), the Fetal Health Locus of Control (FHLC) and the study questionnaire. RESULTS: Thirteen women (2.4%) refused to participate in the survey. Of the 548 women who completed the questionnaires 36 (6.6%) reported physical abuse during the current pregnancy and 60 (10.9%) before it. There were no significant differences in rates of abuse between settings. Of the women abused during the pregnancy 23 (63.9%) reported increased abuse during the pregnancy, and 28 (77.8%) remained with the abuser. Twenty-four pregnant women (66.7%) received medical treatment for abuse, but only 1 (2.8%) told her prenatal care provider of the abuse. Factor analysis revealed three factors associated with physical abuse in pregnancy: "social instability" (comprising low age, unmarried status, lower level of education, unemployment and unplanned pregnancy), "unhealthy lifestyle" (comprising poor diet, alcohol use, illicit drug use and emotional problems) and "physical health problems" (comprising health problems and prescription drug use). The GHQ scores showed that the abused women were significantly more emotionally distressed than the nonabused women (p