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PubMed1992

Menstrual and reproductive factors and breast cancer in women with family history of the disease.

The relationship between socio-economic indicators, body mass, reproductive and menstrual factors and risk of "familial" breast cancer has been analyzed using data from a large case-control study of breast cancer conducted in Italy. A total of 3,037 breast-cancer patients aged 75 years or less admitted to a network of hospitals in the Greater Milan area were interviewed. Controls were 2,569 women aged 75 or less, admitted for acute conditions to the same network of hospitals where cases had been identified. Women were not included as controls if they had been admitted for gynecological, hormonal or neoplastic diseases. A total of 331 cases and 121 controls reported a family history of breast cancer in their first-degree relatives, with a family history tended to be more educated and of higher social class than controls with family history, but these differences were not statistically significant. No relationship emerged with marital status and body-mass index. The estimated multivariate relative risks were, compared with nulliparous women, respectively 0.9, 1.2 and 1.2 for women reporting 1, 2 and 3 or more births. The risk of breast cancer was also greater in women reporting one or more spontaneous abortions: compared with those who did not, the estimated relative risk was 1.9 (95% confidence interval 0.8 to 3.7). Relative to women reporting their first birth below age 25, the estimated relative risks were 1.3 and 0.9 in those reporting it at age 25 to 29 and 30 or more respectively. Likewise, no consistent relationship emerged with lifelong menstrual pattern and menopausal status. These results suggest that menstrual and reproductive factors do not play an important role in the risk of breast cancer in women with a history of the disease in first-degree relatives.

Abortion, Spontaneous↗
PubMed1993

Family planning education helps build self-esteem.

I got married at the age of 20. In our community, generally girls are married off at 15 or 16, but my marriage was delayed according to my father's and my wishes. I did not desire to have my first child immediately. My husband and I are very young and I did not want to assume maternal responsibilities so early in life. Picking up courage, I spoke to my husband. On learning that he had similar views, I was very relieved. I belong to a middle-class family. Due to an absence of a high school in the village. I was forced to drop out of school. Young girls in our community are not allowed to move freely within the village, much less the outside world. But when I was 19, I got the opportunity to gain a lot of information on family planning, health, personal hygiene and good nutrition as part of the Better Life Project. I also learned beauty skills, embroidery, knitting and video film-making. Often I share the information and skills I learned with others. I have even advised my brother's wives about proper child care and immunization. Now that I have a good relationship with the unmarried sister of my husband, I sometimes tell her whatever I have learned. I have felt a great change in myself. My earlier inhibitions in talking to people have dropped, and I can entertain and speak freely with guests who come home. I am more confident about traveling outside my village to other places alone or with company. Learning to operate a video camera and producing a film was my favorite experience. I discovered that I can do what is normally said to be the work of boys only. Sometimes I think that if I had not learned new skills, I would not have been able to share my feelings about family planning with my husband. My mother-in-law is also agreeable to our decision about waiting to have children because both my brothers-in-law have large families. However, I have to face my sisters-in-law who taunt me about my childless status. The problem now is that my husband is not satisfied using condoms. I have decided to consult the doctor at the mobile clinic about taking pills or other methods of contraception.

Asia↗
PubMed1986

Breast cancer risk in relation to early oral contraceptive use.

It has been suggested that the risk of breast cancer is increased by oral contraceptive use before the first birth, or by use before age 25, particularly if certain formulations are used. These hypotheses were evaluated in a hospital-based case-control study. A total of 521 patients under age 45 with breast cancer were compared with 521 controls matched for age, time of interview, and geographic area. Oral contraceptive use before the first birth was reported by 155 patients and 137 controls. With allowance for confounding by multivariate analysis, the estimated relative risk was 1.0 (95% confidence interval, 0.6-1.5). The estimate was 1.0 (0.2-3.9) for any use among nulliparous women and 0.6 (0.3-1.3) for use before the first birth among parous women. Use before age 25 was reported by 145 patients and 141 controls, and the multivariate relative risk estimate was 1.0 (0.7-1.6); the results were similar when use of specific formulations was examined. For oral contraceptive use before either the first birth or age 25, the relative risk estimates were compatible with 1.0 for use of five or more years' duration or an interval since first use of at least 15 years. There was also no evidence of an increased risk in any subgroup including those at increased underlying risk because of factors such as a family history of breast cancer or a history of cystic breast disease. The findings suggest that, up to age 45, the risk of breast cancer is not influenced by the use of oral contraceptives before the first birth or before age 25 even if the use lasted for five or more years.

Adult↗
PubMed1987

Respiratory distress syndrome in second-born versus first-born twins. A matched case-control analysis.

The well-known increased risk of the respiratory distress syndrome in a twin born second as compared with the twin born first is usually attributed to the second twin's predisposition to depression at birth ("asphyxia"). We analyzed the etiologic roles of birth order, presentation, and depression at birth in the development of the respiratory distress syndrome in matched case-control populations drawn from 221 preterm twin pairs. Among the 39 twin pairs discordant for respiratory distress syndrome, the second twin was the affected member in 31 pairs. Second birth order was the only independent risk factor, but only in vaginal deliveries (matched odds ratio, 14.2; 95 percent confidence interval, 2.5 to 81.1). Second twins delivered abdominally did not have an increased risk relative to first twins (odds ratio, 0.9; confidence interval, 0 to 17.8). When depression at birth was evaluated as an outcome variable, malpresentation, rather than birth order, was the major risk factor (independent matched odds ratios of 2.7 [confidence interval, 1.0 to 7.5] and 1.3 [0.7 to 2.5], respectively). Thus, second twins' increased risk of respiratory distress syndrome cannot be explained by a predisposition to depression at birth; a more important factor may be that second twins do not benefit from the salutary effects of labor to the same extent as first twins.

Asphyxia Neonatorum↗
PubMed1976

A modification of a continuous time model for first conception.

The interval between marriage and the first conception leading to a live birth plays an important role in the determination of fertility components. Several probability models (Potter and Parker, 1964; Singh, 1961, 1964, 1967) based on varying sets of assumptions relating to this interval have been propounded in the recent past. All of them are based on the assumption that the females under study are susceptible to conception at the time of marriage. However, in certain situations, where some of the females already pregnant at the time of marriage report to have conceived within a short interval following marriage, this condition is not satisfied and these models become unsuitable. A probability distribution which is an inflated form of the continuous model proposed by Singh, for the time of the first conception leading to a live birth, is presented in this paper. It describes reasonably well the data on first conception times in the context of premarital conceptions. Simple expressions for the maximum likelihood estimators of the parameters involved in the model are obtained and a method for finding the asymptotic covariance matrix of the estimators is outlined. The model is applied to four sets of data.

Female↗
PubMed2000

Risk factors and age-incidence relationships for contralateral breast cancer.

The nation-wide Swedish Family-Cancer Database was used to analyze the risk of contralateral breast cancer among 72,092 women with unilateral breast cancer. Contralateral breast cancer, defined as being diagnosed 6 months or more after the first breast cancer, affected 2,529 women (3.5%). In a young age group the incidence of contralateral breast cancer was 50 times higher than the incidence of first breast cancer; for all contralateral breast cancer the difference was 5-fold. Because only 1 breast was at risk for contralateral breast cancer, the true differences to unilateral cancer were 2 times higher. The age-incidence relationship was unusual, exhibiting a high incidence (800/10(5) person-years) component at an early age (25 to 49 years) and a lower incidence (460/10(5) person-years) component at a later age (50-80 years). The discrete components suggest population heterogeneity. Age at diagnosis of the first breast cancer and family history of breast cancer associated with the risk of contralateral breast cancer. Other, weaker risk factors were birth cohort, age at first childbirth, parity and interval between first and second breast cancer. The incidence of familial contralateral breast cancer was 1. 5 times higher than that of sporadic disease, and its age-incidence curve also exhibited 2 separate components. The age-incidence relationships of contralateral breast cancer suggest that the disease affects a small and heterogeneous susceptible population.

Adult↗
PubMedDate not supplied

Risk factors for stillbirths in a rural community.

To determine the risk factors for stillbirth, a case-control study was carried out in a rural community of Haryana. Stillbirths (cases) were identified retrospectively from a household survey, while the controls, matched individually with each case for the month of birth, were live born infants from the same neighbourhood as the case. The stillbirth rate in the study population was 26.8 per 1000 (68/2539) births. The distribution of socio-economic and environmental factors was similar in the cases and the controls (P > 0.05). Multivariate analysis indicated higher risk of stillbirth for first order births (Odds Ratio [OR] 7.9, Confidence Interval [CI] 2.1-29.2, P 0.002), history of prior stillbirths/child deaths (OR 15.2, CI 2.3-98.2, P 0.004), and absence of antenatal care (OR 3.3, CI 0.9-14.3, P 0.07). Mothers' age, birth interval (< 24 months), delivery place (hospital or home) and type of birth attendant (trained vs untrained) did not show significant influence on the risk of stillbirth. An improvement in the coverage of antenatal care in socio-economically weaker rural community is suggested as the most appropriate strategy for reducing the high stillbirth rate.

Case-Control Studies↗
PubMed1998

Guinea-pig productivity under traditional management.

Results of a 12 month study of traditional guinea-pig production in the western highlands of Cameroon are reported. The mean age of guinea-pigs (Cavia porcellus L.) at first parturition, kidding interval and litter size at birth were 126.30 +/- 10.40 d, 64.8 +/- 1.70 d and 1.63 +/- 0.26 kids respectively. The annual reproductive rate was 9.18 kids/breeding doe while the doe post-partum weight was 530 g. Mean body weights at birth, presumed weaning (21 d) and 15 weeks of age were 78.36 +/- 3.20, 147.51 +/- 8.10 and 418.88 +/- 32 g respectively. Type of birth and sex had a significant effect on body weight at all ages. Birth weight dropped significantly from 83.88 +/- 2.87 g for singles to 81.57 +/- 3.40 g for twins, 74.25 +/- 2.39 g for triplets and 73.75 +/- 4.12 g for quadruplets. These differences were maintained to maturity (15 weeks). Males were generally heavier than females. Mortality rates were relatively high among kids: 24% at birth, 39% at 3 weeks and 40% at 15 weeks. Productivity indices were 0.827 kg of young weaned per doe per year, 1560 g of young weaned per kg of doe per year and 2.52 kg of young weaned per kg metabolic weight (kg 0.75) of female per year.

Animal Feed↗
PubMed1979

A study of the disposition of alpha-methyldopa in newborn infants following its administration to the mother for the treatment of hypertension during pregnancy.

1 The nine infants participating in this study were born to mothers who received continuous therapy with alpha-methyldopa (0.75-2.0 g/day) for several weeks extending to the time of delivery. 2 The concentration of free and total (free plus conjugated) alpha-methyldopa was determined by gas chromatography-mass spectrometry in amniotic fluid, umbilical cord plasma and maternal plasma at delivery; also in urine collected over time intervals from neonates during the first days after birth. 3 The results indicate that alpha-methyldopa administered to the mother is present in the infant at birth at a level comparable to the maternal level and persists for some days. The ratio of conjugated to free drug increases with time after birth. 4 The excretion of free and conjugated alpha-methyldopa in the urine indicated that the drug is slowly eliminated in the neonate by excretion in the urine and apparently by metabolism, mainly to the sulphate conjugate. 5 The concentration of free and conjugated alpha-methyldopa in amniotic fluid tended to be higher than in umbilical cord plasma but lower than in neonatal urine, conjugated drug predominated.

Amniotic Fluid↗
PubMed1991

Chemical sympathectomy alters the development of hypertension in miniature swine.

To determine if the neurotoxin 6-hydroxydopamine could be used to chemically sympathectomize neonatal miniature swine, eight newborn swine were treated with 6-hydroxydopamine beginning on the first day after birth and continuing at regular intervals for the next 6 months. Six littermates served as controls and received vehicle injections. A significant reduction in the pressor response to intravenous tyramine (95%) and in the tissue norepinephrine content of the kidneys, left ventricle, and gastrocnemius muscle (more than 93%) provided evidence for an effective long-term sympathectomy in the 6-hydroxydopamine-treated animals. In addition, the blood pressure response of these young, chemically sympathectomized swine to chronic deoxycorticosterone acetate treatment was evaluated. Mean arterial pressure before deoxycorticosterone was similar in the 6-hydroxydopamine-treated (116 +/- 2 mm Hg) and control (125 +/- 5 mm Hg) groups. One week after deoxycorticosterone, mean arterial pressure had risen significantly by 20-22 mm Hg in both groups. Blood pressure continued to increase in the control group, reaching a value of 163 +/- 6 mm Hg by the third week after treatment. In contrast, mean arterial pressure in the 6-hydroxydopamine group did not increase further during weeks 2 and 3 after deoxycorticosterone. In conclusion, chronic treatment of neonatal swine with 6-hydroxydopamine produced an animal model with an effective, general, peripheral sympathectomy. The significant attenuation of the hypertensive response in these sympathectomized animals lends further support to the hypothesis that an intact sympathetic nervous system is necessary for the full expression of deoxycorticosterone hypertension in miniature swine.

Animals↗
PubMed1979

Multiple sclerosis and housedogs: a case-control study.

A case-control study was conducted to examine the possible association between ownership of housedogs early in life and later development of multiple sclerosis (MS). Sixty MS patients were compared with 60 neighborhood controls matched for age, sex, and race. There was no significant difference between cases and matched controls in housedog ownership, duration of ownership, or age at first exposure to housedogs over the interval from birth to 19 years of age.

Adolescent↗
PubMed1986

[Age, parity, and time in fertility].

The authors analyze fertility trends in Japan from 1935 to 1969 using "vital statistics data upon which age-parity adjusted net reproduction tables were constructed for 35 different female birth cohorts." These tables are used to calculate "cohort net reproduction rate and total fertility rate by parity and age, [as well as] mean age at first birth, second birth, etc. and average length of birth interval in each cohort." (summary in ENG)

Age Factors↗
PubMed1993

Child day care, smoking by caregivers, and lower respiratory tract illness in the first 3 years of life. Group Health Medical Associates.

BACKGROUND: Day-care attendance has been associated with an increased risk of hospitalization for lower respiratory tract illnesses (LRIs). This study examines, in a health maintenance organization population of children, the associations between child day care and the occurrence of LRIs in the first 3 years of life. Smoking by caregivers and a possible protective effect of longer day-care enrollment in relation to LRIs are also addressed. METHODS: Information on day-care arrangements was elicited from 1006 parents of infants for five age intervals in the first 3 years of life: birth through 3 months, 4 to 6 months, 6 to 12 months, 1 to 2 years, and 2 to 3 years. Data on LRIs in the first 3 years of life were recorded by pediatricians at the time of the acute illnesses. RESULTS: After controlling for other risk factors, the presence of three or more unrelated children in the care setting was associated with significant risks of LRI of up to twofold or more from 4 months of age to 3 years. Type of care setting was not a significant risk factor during this time period. In the third year of life, the risk of wheezing LRI in the presence of a smoking caregiver was more than threefold for those in another residential home setting. No significant protective effect against LRIs in the third year of life associated with longer prior day-care enrollment was demonstrated. CONCLUSION: The presence of three or more unrelated children in the care setting and the presence of a smoking caregiver were significant independent risk factors for LRIs during the first 3 years of life. Prolonged day-care did not protect against LRIs in the third year of life.

Caregivers↗
PubMed1980

Triplet pregnancy: a review of 27 cases.

Analysis of 27 consecutive triplet pregnancies seen at the University Teaching Hospital in Enugu, Nigeria, from 1972 to 1979 revealed an incidence of one in 1014 live births; three of these mothers had had a previous twin pregnancy. Overall fetal mortality was 30.9%, with babies of older women faring better than those of the younger. The fetal death rate was 1.8 times greater in the absence of antenatal supervision. Although the male infant was generally heavier at birth, sex did not influence survival and neither predominated. Surprisingly, vertex delivery, independent of birth order, was associated with the worst prognosis. All babies of sets having a combined birth weight of 2800 gm and under died; all those 5440 gm and above survived. Maturity, rather than birth weight, determined fetal survival, which was also unaffected by time interval between deliveries of a set. The first triplet did have the least birth hazard.

Adolescent↗
PubMed1983

Change in observed birth weight associated with change in maternal cigarette smoking.

Using data collected by the National Collaborative Perinatal Project of the National Institute of Neurological and Communicative Disorders and Stroke, the author paired on characteristics of their first study pregnancy 319 white women who reported a change in smoking habits for two successive pregnancies with 319 women who reported no change in smoking behavior. Matching was based upon similar birth weight, interval between births, smoking behavior, sex, and parity of the first of two study births. Divergent smoking behavior for each pair by the time of the second study birth allowed assessment of smoking as a treatment effect. Members of each pair who started smoking prior to the second birth while not smoking for the first, had infants with an average birth weight of 67 g less than infants of their controls who did not start smoking and 36 g less than their previous infant. Among infants whose mothers reported smoking prior to the first study birth, a significant increase in birth weight was observed over infants of controls for women who quit smoking prior to the second study birth (average, 169 g). Taken at face value, this rebound in birth weight is not consistent with an immutable, innate predisposition to lower birth weight among those disposed to smoking.

Adult↗
PubMed2000

The effects of branches on prepartum nest building in gilts with access to straw.

Sows farrowing in a semi-natural environment terminate nest building 1-7 h prior to parturition after having built a nest for which a variety of materials are used. No nest-building behaviour occurs during parturition and the sows remain lying in the nest throughout most of the farrowing. In contrast, many intensively housed sows are restless during farrowing. To investigate whether gilts housed indoors would use branches for nest building and whether access to branches would affect the termination of nest building and parturient behaviour, we studied gilts housed individually in pens designed to stimulate natural nest building. The control group (n=21) had unlimited access to straw and the experimental group (n=21) had unlimited access to straw and branches. During nest building all the gilts used straw and all the experimental gilts also used branches. In the experimental group the interval from termination of nest building to birth of the first piglet (BFP) was significantly longer than in the control group (132 versus 58 min, P=0.04). In the experimental group, nest-building behaviour was also performed by fewer individuals during the interval from BFP until 2 h after than in the control group (38% versus 71% of the gilts, P=0.03). Gilts that performed nest building during this interval carried out more postural changes (P<0.001) and spent less time in lateral recumbency (P=0.001) than gilts which did not perform nest building. On average, gilts that performed nest building behaviour after BFP (n=26) spent 54% of the first 2 h of parturition in lateral recumbency and carried out 16 postural changes. Gilts that did not perform nest building behaviour during this interval (n=16) spent 85% of the time in lateral recumbency and carried out five postural changes. In 10 gilts that were selected randomly from the experimental group nest building was studied in more detail. In these gilts nest building peaked between 17 and 6 h prepartum. There was no difference in amount of behaviour directed towards straw and amount of behaviour directed towards branches.The results indicate that the termination of nest building in sows is under environmental feedback control. When only straw was provided the nests did not have much of a lasting structure. However, when gilts had access to straw and branches more structured and functional nests could be built. These nests may have been more effective in reducing the motivation for nest building prior to the onset of parturition.

Journal Article↗
PubMed1980

The effect of diazepam administration during pregnancy or labor on the heart rate variability of the newborn infant.

Maternal diazepam medication during labor reduces beat-to-beat variability of the fetal heart rate. In this study, the prolongation of the effect was examined in the newborn. The mother received diazepam: (A) during labor as a tranquilizer, (B) daily in low doses at the end of pregnancy, or (C) in high doses i.v. for (pre-)eclampsia. A control group had no analgesic or sedative during pregnancy or labor. The electrocardiogram (ECG) was recorded daily from each newborn during the first 6 days after birth. After preprocessing of the ECG, the median R-R interval, the long-term irregularity index (LTI index) and the interval difference index (ID index) were calculated. A cubic spline interpolation method was applied to compare the various groups with respect to these heart rate parameters. The median R-R interval showed no particular differences in trend for all groups. The LTI index was decreased in the first days after birth in the chronic diazepam (B), and in the diazepam infusion groups (C), but statistical significance was not reached. The ID index was significantly decreased in the first 1-2 days in the newborns of the acute and chronic diazepam group. In the diazepam infusion group, an even longer lasting effect was observed. Maternal diazepam medication affects the beat-to-beat variability in the newborn. The duration of the effect is dependent on dosage and route of administration.

Diazepam↗
PubMed2004

Vaginal bleeding during pregnancy and preterm birth.

This study investigated the relation between self-reported vaginal bleeding during pregnancy and preterm birth in a prospective cohort of 2,829 pregnant women enrolled from prenatal clinics between 1995 and 2000 in central North Carolina. The overall association between vaginal bleeding and preterm birth was modest (risk ratio (RR) = 1.3, 95% confidence interval (CI): 1.1, 1.6). Bleeding in the first trimester only was associated with earlier preterm birth (< or =34 weeks' gestation) (RR = 1.6, 95% CI: 1.1, 2.4) and preterm birth due to preterm premature rupture of the membranes (PPROM) (RR = 1.9, 95% CI: 1.1, 3.3). Bleeding in both trimesters was associated with preterm birth due to preterm labor (RR = 3.6, 95% CI: 1.9, 6.8). Bleeding of multiple episodes, on multiple days, and with more total blood loss was associated with an approximate twofold increased risk of earlier preterm birth, PPROM, and preterm labor. In contrast, bleeding in the second trimester only, of a single episode, on a single day, and with less total blood loss was not associated with any category of preterm birth. Vaginal bleeding was not associated with preterm birth among African Amercians (RR = 1.2, 95% CI: 0.9, 1.7). This study indicates that more intense but not less intense bleeding is associated with earlier preterm birth and spontaneous preterm birth presenting as PPROM or preterm labor, and it suggests that bleeding is less predictive of preterm birth among African-American compared with White women.

Adult↗