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PubMed1996

Abortion and breast cancer risk.

The relationship between spontaneous and induced abortions and breast cancer risk was analyzed using data from a case-control study conducted between June 1991 and February 1994 in 6 Italian centers on 2,569 histologically confirmed incident breast cancer cases and 2,588 controls admitted to hospital for a wide range of acute, non-neoplastic, non-hormone-related diseases. One or more abortions were reported by 31% of cases and 32% of controls, corresponding to a multivariate odds ratio (OR) of 1.0 (95% confidence interval [CI], 0.8-1.1). No trend in risk was observed with increasing number of total abortions or spontaneous and induced abortions separately. No significant relationship was found between the risk of breast cancer and history of spontaneous or induced or total abortions in separate strata of age at diagnosis, number of children, time of abortion in relation to first birth and family history of breast cancer. When abortion was the outcome of the first pregnancy, the OR was 1.2 for spontaneous and 1.3 for induced abortion, in relation to women with birth as outcome of the first pregnancy, and 1.0 and 1.1, respectively, when the reference category was nulligravidae. Thus, our results indicate a lack of association between induced and spontaneous abortions and breast cancer risk.

Abortion, Induced↗
PubMed1994

Association of time to pregnancy and the outcome of pregnancy.

OBJECTIVE: To examine the relationship of subfertility with miscarriage, low birth weight, and preterm delivery. DESIGN: Comparison of time to pregnancy distributions between pregnancies that had different outcomes. Three comparisons were made: (a) miscarriages with live births; within live births, (b) low birth weight infant (up to 2,500 grams) or not low birth weight; (c) preterm birth (37 weeks or less) or not preterm. Cox regression was used to adjust for covariates. POPULATION: All first pregnancies were analyzed from the National Child Development Study, a large survey of young adults aged 33 years, which is nationally representative of the British-born population. MAIN OUTCOME MEASURES: The distribution of the time taken to conceive (time to pregnancy), miscarriage, birth weight, and preterm delivery. RESULTS: Pregnancies that ended in miscarriage tended to take 23% longer to conceive, after adjustment for the other variables. Pregnancies that resulted in preterm delivery tended to take 15% longer to conceive. There was no statistically significant association with low birth weight. CONCLUSIONS: Delay in time to conception is a risk factor for poor obstetric outcome, irrespective of medical intervention.

Abortion, Spontaneous↗
PubMed1989

Oral contraceptives and breast cancer.

A population-based case-control study of oral contraceptive use and breast cancer was carried out among young women (less than 43 years of age) at Group Health Cooperative of Puget Sound, Seattle, Washington. Use of oral contraceptives before first pregnancy did not materially differ between cases or controls. The rate ratio estimate of breast cancer incidence in women who had used oral contraceptives before first pregnancy compared to those who had not was 0.9 (95% CI = 0.4, 2.1). There were no meaningful patterns of association between breast cancer and duration of use or formulation of oral contraceptive used before first pregnancy.

Adult↗
PubMed2002

Complexities in ETS-domain transcription factor function and regulation: lessons from the TCF (ternary complex factor) subfamily. The Colworth Medal Lecture.

The ETS-domain transcription factor family can be divided into a series of subfamilies. Elk-1 represents the founding member of the ternary complex factor (TCF) subfamily. By focusing on the TCF subfamily, we can demonstrate the complexities that exist in the function and regulation of ETS-domain transcription factors. This article focuses on Elk-1 in detail and summarizes the functions of other TCFs. The key themes covered include the domain structure of the TCFs, the mechanisms of complex formation with serum response factor, regulation of TCFs by mitogen-activated protein kinase cascades, and transcriptional regulatory properties of the TCFs. Finally, the emerging role of the TCFs in vivo is discussed. A picture is developing indicating that, while these proteins exhibit significant sequence and functional conservation, key differences in their structure and regulation are being identified which may relate to unique functions of these proteins in vivo.

Amino Acid Sequence↗
PubMed1994

Male and female factors in fertility.

Fertility is affected by the age of the female partner, but not that of the male partner, in the age ranges within which most attempts at conception occur. However, the literature on the effect of the smoking status of each partner is inconclusive. As part of a longitudinal study representative of all people born in Britain in 1958, 11,407 people were interviewed in 1991, of whom 3,132 female and 2,576 male cohort members had had or fathered at least one pregnancy. The outcome measure was the time to pregnancy of the first pregnancy (live births only), and the antecedent variables were the cohort member's age at that time and both partner's smoking habits and educational levels. Unadjusted analysis demonstrated that both the time to pregnancy and clinical subfertility were associated with higher maternal but not paternal age and with the smoking habits and educational levels of both parents. Multivariate analysis showed that paternal smoking failed to enter the model if the educational variables were also included. Findings were similar in the two separate analyses on male and female cohort members. This study confirms previous findings on the relative importance of maternal and paternal age in this age range. Maternal smoking affects fertility, but earlier reports of an apparent effect of paternal smoking may be due to confounding with socioeconomic status.

Adult↗
PubMedDate not supplied

Probabilities of intercourse and conception among U.S. teenage women, 1971 and 1976.

One in five U.S. females have had intercourse by age 16, and two-thirds, by age 19. Almost all the experience is premarital. One in 10 U.S. women get pregnant before age 17; one-quarter before they are 19, and eight in 10 of these pregnancies are premarital. More than one-third of those who are sexually active premaritally have a premarital pregnancy before they turn 19, one-quarter by the time they are 17.

Actuarial Analysis↗
PubMed1978

Intermediate objectives for the monitoring of family planning services.

Since progress during the early stages of a program cannot easily be measured in terms of the ultimate objectives, there is need to develop a set of intermediate indicators for purposes of necessary evaluation and monitoring. Family planning programs suggest a series of useful intermediate objectives that have a clear cause-and-effect relationship with regard to their ultimate goals. It is important that they be expressed as specific targets. They should provide for a numerical definition of the target population; a given time frame; a service design which takes into account patient load, personnel performance, and service capacities; and a record system that can readily retrieve information about service utilization and also identify each patient individually. At the same time, allowance should be made for periodic review and adjustments in light of modifications that are bound to occur in the composition of the target population as well as possible changes of a sociopolitical nature that might affect the program's scope.

Adolescent↗
PubMed1999

Breast cancer in relation to some reproductive factors.

Breast cancer is one of the most commonly occurring cancers in females in the Eastern Mediterranean Region. In Egypt women's breast cancer had the highest frequency. The present study was conducted to study the association between breast cancer and some reproductive factors as well as to find out (if possible) predictors for occurrence of breast cancer. A hospital based case control study was carried out in Alexandria Main University Hospital where, 129 histopathologically confirmed incident primary breast cancer cases were included. An equal number of a control group matched by age were selected from the visitors of the same hospital. Data related to women's reproductive period were collected from both cases and controls. The results revealed that there was no statistically significant difference between cases and controls as regards menopausal status, menstruation span, number of births, spontaneous and induced abortion, twin birth, breast feeding and use of oral contraceptives. There was an increasing risk of breast cancer, with the presence of positive family history of breast cancer decreasing age at menarche, increasing age at first full-term pregnancy, widening of the interval between menarche and first full-term pregnancy, increasing age at last full-term pregnancy and shortening of the interval since last birth. Multiple logistic regression analysis revealed that positive family history of breast cancer, young age at menarche, late age at last full-term pregnancy and wide inter-birth interval were significant predictors for occurrence of breast cancer. The results of the study pinpoint that conduction of public health education programmes focusing on the modifiable risk factors are required.

Adolescent↗
PubMed1997

The impact of pregnancy on the long-term weight gain of primiparous women in England.

OBJECTIVES: To investigate the impact of pregnancy on long-term weight gain of primiparous mothers in England, and to identify potential risk factors for maternal obesity. DESIGN: A retrospective, repeat-pregnancy study which examined the change in maternal body weight from the beginning of the first successful pregnancy to the beginning of the second. SUBJECTS: Two hundred and forty-three mothers, all of whom had been weighed during the first trimester of their first and second pregnancies, and none of whom had fallen pregnant less than 12 months after the birth of their first child. MEASUREMENTS: Sociodemographic, behavioural, medical, obstetric and perinatal data, together with antenatal measurements of maternal body weight and height, were extracted from each mother's obstetric notes. A comprehensive survey of weighing scales used at all antenatal clinics was undertaken. RESULTS: After accounting for the effect of ageing, there was no significant long-term increase in mean maternal body weight following the first pregnancy (95% Confidence Intervals: -0.82-0.28kg). While most mothers (70.8%) gained 1.0 kg or less, 24.7% gained more than 1.54 kg. Even after accounting for the maximum error in clinic scales, 14.8% of the mothers gained 1.54 kg or more in association with their first pregnancy. Mothers with higher BMIs at the beginning of their first pregnancy, who gained more weight during pregnancy, gave birth to heavier babies and had longer intervals between their pregnancies, gained significantly more weight from one pregnancy to the next. CONCLUSIONS: Pregnancy has little impact on the mean weight gain of primiparous women from England, who have a low prevalence of obesity (BMI > or = 26.0, 25.5%). Nevertheless, pregnancy may be associated with a permanent increase in maternal body weight simply because it is a period of positive energy balance during which some women gain excessive weight. Other factors, such as prepregnant BMI, determine whether long-term weight gain actually occurs.

Adult↗
PubMed1976

Changes in cardiac function during and after pregnancy expressed by systolic time intervals.

Hemodynamic changes during the first and third trimester in pregnancy and in the first week of puerperium were evaluated by non-invasive measurements of Systolic Time Intervals (STI) in supine and left lateral position. The Pre-ejection Period (PEP) was found to shorten significantly in pregnancy and the puerperium due to the increased blood volume. The electro-mechanical systole (QS2) and left ventricular ejection time (LVET) were shortened too, while PEP/LVET-ratio was increased in the third trimester due to the mechanical compression of the gravid uterus on the inferior vena cava. A lengthening of QS2 and LVET and a decreased PEP and P/L-ratio were demonstrated in the third trimester in lateral position when the pressure of the enlarged uterus was eliminated. Heart rate (HR) increased in late pregnancy as well as after delivery, while arterial blood pressure (BP) only underwent minor changes. Employment of the STI seems to provide more useful information about the changes cardiac function during gestation than HR and BP does. The measurements of STI can be repeated without any risk or inconvenience to the patients.

Adult↗
PubMed2000

Enduring effects of nurse home visitation on maternal life course: a 3-year follow-up of a randomized trial.

CONTEXT: A home visitation program using nurses to improve maternal and child outcomes had favorable results in a randomized trial with a primarily white, semirural population. Many of the short-term findings have been replicated with urban blacks, but whether the program will continue to demonstrate effectiveness after its conclusion is uncertain. OBJECTIVE: To determine the effectiveness of a prenatal and infancy home visitation program on the maternal life course of women in an urban environment 3 years after the program ended. DESIGN AND SETTING: Three-year follow-up of a randomized controlled trial of women seen consecutively between June 1990 and August 1991 at an obstetrical clinic in Memphis, Tenn, who were enrolled in a visitation program for 2 years after the birth of their first child. PARTICIPANTS: A cohort of 743 women who were primarily black, were pregnant for less than 29 weeks, had no previous live births, and had at least 2 sociodemographic risk factors (unmarried, <12 years of education, or unemployed). INTERVENTION: An average of 7 (range, 0-18) home visits during pregnancy and 26 (range, 0-71) from birth to the child's second birthday. MAIN OUTCOME MEASURES: Rate of subsequent pregnancy, mean interval between first and second birth, and mean number of months of welfare use. RESULTS: Compared with the control group, women who received home visits by nurses had fewer subsequent pregnancies (1.15 vs 1.34; P=.03), fewer closely spaced subsequent pregnancies (0.22 vs 0.32; P=.03), longer intervals between the birth of the first and second child (30.25 vs 26.60 months; P=.004), and fewer months of using Aid to Families with Dependent Children (32.55 vs 36.19; P=.01) and food stamps (41.57 vs 45.04; P=.005). Compared with the effect of the program while the program was in operation, the effect after it ended was essentially equal for Aid to Families with Dependent Children, greater for food stamps, greater for rates of closely spaced subsequent pregnancies, and smaller for rates of subsequent pregnancy overall. CONCLUSIONS: We found enduring effects of a home visitation program on the lives of black women living in an urban setting. While these results were smaller in magnitude than those achieved in a previous trial with white women living in a semirural setting, the direction of the effects was consistent across the 2 studies.

Black or African American↗
PubMed2005

Recurrence risk in hyperemesis gravidarum.

OBJECTIVES: To compare the risk of hyperemesis gravidarum in second pregnancies in women with and without hyperemesis in their first pregnancy, and to determine if this risk changes with changes in paternity or with the interval between deliveries. DESIGN: Cohort study. SETTING: Data from the population-based Medical Birth Registry of Norway, 1967-1998. Sample All women in the registry with records of their first and second singleton delivery, a total of 547,238 women. METHODS: The relative risk of hyperemesis in the second delivery was estimated as odds ratios (ORs) in logistic regression models, controlling for potential confounding factors. MAIN OUTCOME MEASURES: The main outcome measure was the risk of hyperemesis in the second pregnancy according to hyperemesis in the first pregnancy, interval between deliveries and change in paternity. RESULTS: The risk of hyperemesis was 15.2% in the second pregnancy in women with and 0.7% in women without previous hyperemesis [OR=26.4, 95% confidence interval (CI) 24.2, 28.7]. The OR did not change after adjustment for maternal age, change in paternity, period of the first delivery and time interval between deliveries. After a change in paternity, the risk of recurrent hyperemesis was 10.9% compared with 16.0% in women without a change in paternity [adjusted OR (aOR)=0.60, 95% CI 0.39, 0.92]. The risk of hyperemesis in the second pregnancy increased with increasing time interval between deliveries, but only in women with no previous hyperemesis. CONCLUSIONS: The primary finding was the high risk of recurrence observed in women with hyperemesis in the first pregnancy. The risk was reduced by a change in paternity. For women with no previous hyperemesis, a long interval between births slightly increased the risk of hyperemesis in the second pregnancy. Further studies are needed to explore the relative impact of genetic and environmental factors and their possible interactions in hyperemesis gravidarum.

Adult↗
PubMedDate not supplied

[Effect of beta-carotin serum concentration on the reproductive performance in dairy cows].

The aim of the following investigation was to study the effect of beta-carotin serum concentrations on reproductive performance in dairy cows. Blood samples were collected from 201 cows 3 to 4 weeks antepartum, 1 to 2 weeks postpartum and at the time of insemination. Concentrations of beta-carotin in blood serum were determined via HPLC. The incidence of retained placental fetal membranes, endometritis, ovarian cysts as well as the beginning of the oestrous cycle and various measures of fertility such as first service conception rate, pregnancy index, interval from calving to first insemination, interval from calving to conception, interval from first insemination to conception and expected calving interval were recorded and analysed. The beta-carotin serum concentrations were not related to the incidence of retained placental fetal membranes, endometritis, ovarian cysts or the onset of cyclicity post partum. Cows with lower beta-carotin concentrations partially seemed to have a reduced reproductive performance than cows with higher beta-carotin concentrations. Overall, our results suggest only a minor relationship between the beta-carotin serum concentration and fertility in dairy cows.

Animals↗
PubMed2006

Prospective study of non-closure or closure of the peritoneum at cesarean delivery in 124 women: Impact of prior peritoneal closure at primary cesarean on the interval time between first cesarean section and the next pregnancy and significant adhesion at second cesarean.

AIM: The aim of this study was to evaluate the effect of non-closure of the peritoneum at cesarean delivery on postoperative complications and the interval time to the next pregnancy, and to investigate the incidence of adhesion following cesarean and the association between adhesion formation and peritoneal closure. METHODS: One hundred and twenty four women scheduled for cesarean section were randomized to either closure of both the visceral and parietal peritoneum (C-group, n = 70) or non-closure (NC-group, n = 54). At repeated cesarean, the levels and extent of adhesion, operating time, and any complications were examined. RESULTS: There was no difference in the incidence of postoperative complications at the first cesarean section. The operating time of the C-group was significantly longer than that of the NC-group. The frequency of analgesic use was significantly higher in the C-group. The time interval from cesarean section to the next pregnancy in the NC-group was significantly shorter than that in the C-group. There are no significant differences between the rates of complications in the C-group and the NC-group at repeated cesarean. The incidence of adhesion in the C-group was significantly higher than that in the NC-group (P < 0.05). The mean total operating time and the mean interval time for skin incision to delivery in the C-group were significantly longer than those in the NC-group (P < 0.05 and P < 0.001, respectively) at repeated cesarean section. CONCLUSIONS: Non-closure of the peritoneum at cesarean delivery appears to have no adverse effect on postoperative recovery, it also decreases the number of analgesic doses and shortens the operating time and may be more desirable in achieving a next pregnancy. The present study demonstrated that surgical peritoneal closure resulted in more advanced adhesion formation. The practice of non-closure of the peritoneum should be performed at cesarean.

Adult↗
PubMed1997

Patterns of prenatal care initiation in Georgia, 1980-1992.

OBJECTIVE: To determine whether characteristics in a woman's first pregnancy were associated with the trimester in which she initiated prenatal care in her second pregnancy. METHODS: Data for white and black women whose first and second pregnancies resulted in singleton live births between 1980 and 1992 were obtained from Georgia birth certificates (n = 177,041). Adjusted relative risks (RRs) for early prenatal care in the second pregnancy were computed by logistic regression models that included trimester of prenatal care initiation, infant outcomes, or maternal conditions in the woman's first pregnancy as the exposure and controlled for maternal age, education, child's year of birth, interval between first and second pregnancy, presence of father's name on the birth certificate, and the interaction between prenatal care and education. Models were stratified by race. RESULTS: Women of both races who initiated prenatal care in the first trimester of their first pregnancies were more likely than those with delayed care to initiate prenatal care in the first trimester of their second pregnancies (RR = 1.25 and 1.63 for white and black women educated beyond high school, respectively). Both white and black women who delivered a baby with very low birth weight (RR = 1.06 and 1.15, respectively) or who suffered an infant death (RR = 1.09 and 1.31, respectively) in their first pregnancies were more likely than those who did not experience these events to begin prenatal care in the first trimester of their second pregnancies. CONCLUSION: Women with some potentially preventable adverse infant outcomes tend to obtain earlier care in their next pregnancy. Unfortunately, women who delayed prenatal care in their first pregnancy frequently delay prenatal care in their next.

Female↗
PubMed1999

Relationships between calf birth weight, prepartum concentrations of plasma energy metabolites and resumption of ovulation postpartum in Limousine suckled beef cows.

The aim of this study was to determine the relationship between energy status before calving and calf birth weight and their potential effects on interval between calving and first ovulation. Sixty-nine Limousine, suckled beef cows were sampled weekly over a 3-yr period during the last 2 m.o. of pregnancy to determine the concentrations of nonesterified fatty acids (NEFA), beta-3-hydroxybutyrate (beta-OHB), glucose and glycerol. After parturition, progesterone concentrations were measured weekly to determine time of resumption of ovulation. Cows were allotted to 3 groups according to calf birth weight (Heavy: > 44 kg, n = 37; Medium: 39 to 43 kg, n = 56; and Light: < 38 kg, n = 45) and to postpartum ovarian resumption of cyclicity (Late: > 11 wk, n = 41; Mid: 7 to 10 wk, n = 57; and Early: < 6 wk, n = 40). Puerperium glycaemia of the dams was steady state (0.66 +/- 0.03 g/L) and was not related to calf birth weight. Plasma NEFA, beta-OHB and glycerol values were higher (P < 0.05) in Heavy than in Medium and Light group dams during the last 4 wk of pregnancy. Interval between calving and first ovulation was significantly longer for primiparous than for multiparous cows (respectively, 9.9 +/- 2.0 and 7.7 +/- 1.4 wk; P < 0.05). Calf birth weight was not related to time of first ovulation. Late primiparous cows had higher NEFA plasma concentrations than Mid and Early group primiparous cows during the last 4 wk of pregnancy, whereas NEFA plasma concentrations were not related to interval between calving and first ovulation in multiparous cows. Thus, lipomobilization increased with calf birth weight during the last 4 wk of pregnancy. High level of body reserves mobilization was associated with delayed first ovulation in primiparous but not in multiparous cows.

3-Hydroxybutyric Acid↗