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Case-control study of increased mammographic breast density response to hormone replacement therapy.

Previous studies have demonstrated an association between current hormone replacement therapy (HRT) use and increased mammographic breast density. Many of these studies have also shown that only 20-35% of women initiating HRT respond in this manner. This subgroup of HRT responders may be at an increased risk of breast cancer. We performed a case-control study to investigate how women who experience increased density in response to HRT (cases) differ from women who do not experience an increase in density with HRT use (controls) with regard to breast cancer risk factors, type of HRT, weight change, and baseline breast density. Participants were female residents of Olmsted County, Minnesota who received routine screening mammograms at the Mayo Clinic. Cases included 172 women identified between the years 1998 and 1999 by Mayo radiologists as having a HRT response. Controls were women who did not experience an increase in mammographic density with HRT use and were matched to cases on age (+/-3 years), menopausal status, duration of HRT, month of initiation of HRT, and months between baseline and follow-up mammograms. Mammograms were obtained from cases and controls before and during HRT therapy. Breast density was read as a four-category Bi-Rads density grade measure and as a quantitative percentage estimate, using a computer-assisted method. Risk factor information was obtained from both chart review and a mammography database of patient-provided information. There was no association between HRT response and first-degree family history of breast cancer [odds ratio (OR), 0.8; 95% confidence interval (CI), 0.4-1.5], parity (OR, 0.8; 95% CI, 0.4-1.7), later age at first birth (OR, 0.8 for age >25 years versus nulliparous women; 95% CI, 0.4-1.8), or history of biopsy (OR, 0.9; 95% CI, 0.6-1.5). There was also no association with baseline weight or change in weight between a woman's baseline and follow-up mammograms. However, there was evidence of an association between HRT response and type of HRT used; women who experienced a mammographic increase in density with HRT had 2.3 greater odds (95% CI, 1.4-3.7) of having taken estrogen-progestin combined therapy than estrogen alone, compared with controls. This association was stronger among women with a baseline weight below the median (OR, 5.2; 95% CI, 1.6-17.6). Also, there was an inverse association between HRT response and baseline density. Because all risk factors examined accounted for only 26% of the variation in the HRT response, genes or other unmeasured factors are thought to be involved.

Aged↗

Hindrances to family planning program: findings from Banke, Nepal.

Reducing population growth through programs is a high priority for many developing countries. Why particularly in the rural regions of these countries, do these initiatives fail? Using a case study of a recent initiative in rural Nepal between 1998 and 2002 as an example, this opinion piece discusses possible reasons for such failure and recommends that a broader strategic approach is necessary, particularly in relation to empowering women in these communities. Banke district, Nepal, is mainly rural, consisting of 47 villages. Scarcity of family planning provisions is a dominant problem in most parts of the district. District Public Health Office (DPHO), the major family service provider lacks resources and technical capabilities. In recent years, non-government organizations (NGOs) have been collaborating and coordinating their efforts with DPHO in order to cover the larger section of the district population. A local NGO called Banke Mahila Arthick Swawlamban Sangathan (BMASS) provided family planning services in 5 of the 47 villages of Banke district, Nepal, from 1998 through 2002. Outreach activities and clinical services were the two major components of BMASS family planning program. Outreach activities included door-to-door/mass counseling, street drama, and condom distribution. Clinical services that included counseling, testing, temporary sterilization, and referrals for permanent sterilization were provided through a centrally located static clinic and mobile clinics. BMASS family planning program had almost no impact in the target villages. There was no significant increase in contraceptive use, people's motivation to limit fertility, and number of people preferring a smaller family size. The contraceptive prevalence rate increased by less than 2% after 2 years of family planning program intervention. More than 80% of the family planning clients were reported to have discontinued contraceptive use within six months. The mean age of women at the time of first child delivery (16.2 years), total fertility rate (six children per woman), and the birth intervals (13-18 months) were reported to be the same for both periods: before and two years after family planning program intervention. Further assessment of the local factors revealed that women's lack of control over fertility and higher number of desired children could have hindered the community's response to BMASS family planning program. In the target villages a woman's fertility is dependent upon the preference of husbands and in-laws. The women in general are not empowered to voice their opinion with regards to delaying fertility, spacing child-births, and limiting the number of children to be born to them. Higher number of desired children in the target villages is the outcome of low cost of child rearing and high benefits from the children. Children not only contribute significantly in household economy and provide old age security to their parents, but also consume less. To be effective, family planning programs need to be integrated into broader societal reforms that address rural economic development and the role of women in society.

Journal Article↗

Pooled analysis of 3 European case-control studies: I. Reproductive factors and risk of epithelial ovarian cancer.

The role of reproductive factors in the aetiology of epithelial ovarian cancer has been re-assessed in a meta-analysis of 3 hospital-based case-control studies conducted in Europe (i.e. Italy, the United Kingdom and Greece), providing a total dataset of 1,140 cases and 2,724 controls. Multiple logistic regression models were used to obtain relative risk (RR) estimates adjusted for study centre, age, socio-cultural indicators, age at menopause, and oral contraceptive use. The risk decreased with increasing number of births and the trend in risk was significant (chi 2(1) = 7.50, p less than 0.01). In comparison to nulliparous women, those who reported 4 or more births had a 40% reduction in risk of ovarian cancer (RR = 0.6, 95% confidence interval, CI: 0.4-0.8). An RR estimate of 1.4 (95% CI: 1.1-1.7) as found, overall, for age of 35 or more at first birth compared to age of 25 or less at first birth. In each stratum and overall, nulliparous women did not appear to be at increased risk compared to those who delayed birth of their first child until age 35 or more. In each study, as well as in the overall dataset, an inverse association between number of abortions and ovarian cancer risk emerged. Overall, the inverse relationship was highly significant, RR estimates for 1 and 2 or more abortions, as compared to none, being 0.9 (95% CI: 0.8 and 1.1) and 0.7 (95% CI: 0.6-0.9) respectively. The effects of parity, age at first birth and number of abortions emerged consistently in various strata of study centre and age.

Abortion, Spontaneous↗

Effect of transatlantic transport on reproduction of agouti and nonagouti deer mice, Peromyscus maniculatus.

In conjunction with establishing colonies of deer mice in the UK, effects of transportation on reproduction in agouti (A) and nonagouti (a) deer mice were assessed. Adults were shipped via ground courier and air freight from Northampton, Massachusetts, USA to Sutton Bonington, Leicestershire, England in February and June. Deer mice were paired upon arrival in Sutton Bonington, whereas matched controls were paired in the original colonies at shipping. To assess reproduction, the following variables were monitored for 110 days for all 96 pairs: number of pairs producing litters, time from pairing to birth, interlitter interval, litter size at birth, and litter size at weaning. Generally, shipping suppressed litter production and delayed its timing, but had less effect on litter size. Overall, 32 of 48 control pairs (67%) produced 69 litters compared with 37 litters from 21 of 48 pairs (44%) after shipping. Pairing-to-first-litter intervals were approximately two oestrous cycles shorter in control animals (39 vs 53 days). Averaged over all litters, litter size was higher in control pairs (4.4 vs 4.0). With respect to genotype, control agouti deer mice were less productive than nonagouti animals, but they reproduced better than nonagoutis after shipping. In control animals, colourmorphs did not differ with respect to litter production or timing, but agouti pairs had smaller litters (first litter: A: 3.1, a: 4.2) and this difference increased at successive litters (third litter A: 3.9, a: 6.0). After shipping, agouti animals produced more litters (A: 22, a: 15), and did so earlier (pairing to birth: A: 47 days, a: 60 days), as well as more frequently (interlitter interval: A: 32 days, a: 51 days). Litter size was also more similar between genotypes after shipping (A: 4.0, a: 4.1). Overall, control agouti animals produced 37% fewer offspring than nonagouti pairs. (A: 116 neonates, a: 185 neonates), but after shipping agouti deer mice produced 43% more offspring than nonagouti animals (A: 87 neonates, a: 61 neonates). In sum, transport stress suppressed reproduction for several weeks after shipping and this suppression was exacerbated in nonagouti deer mice.

Agouti Signaling Protein↗

A population-based study of the risk of recurrence of birth defects.

BACKGROUND: Certain birth defects are known to recur in families, but most estimates of the risk of recurrence have come from clinic-based studies. In this study we estimated the risk of recurrent birth defects using a population-based registry. METHODS: The study was based on the records of the first and second infants delivered by 371,933 women from 1967 through 1989. The records are maintained by the Medical Birth Registry of Norway. For the 9192 women whose first infant had a birth defect, we determined the relative risk of similar and dissimilar defects in the second infant. The reference population was women whose first infant had no defect. RESULTS: Among first infants, 2.5 percent had a birth defect. The mothers of affected first infants were 2.4 times as likely as other women to have second infants with any registered defect. This increased risk was due primarily to an increased (7.6 times higher) risk of the same defect in the second infant as in the first (95 percent confidence interval, 6.5 to 8.8) and secondarily to a slightly increased (1.5 times higher) risk of a different defect in the second infant (95 percent confidence interval, 1.3 to 1.7). Among the women who lived in the same municipality during both pregnancies, the relative risk of having a second infant with the same defect was 11.6, as compared with 5.1 among the women who moved to another municipality after the birth of their first infant (P < 0.001). CONCLUSIONS: Among women whose first infant has a birth defect, the risk of the same defect in the second infant is substantially increased and the risk of a different defect in the second infant is slightly increased. Environment plays a strong part in repeated defects.

Confidence Intervals↗

Mouse exposure and wheeze in the first year of life.

BACKGROUND: Studies have found that exposure to mice is highly prevalent among children with asthma living in urban areas. OBJECTIVE: To examine the relationship between exposure to mice and wheeze in the first year of life. METHODS: We conducted an ongoing prospective birth cohort study of 498 children with a history of allergy or asthma in at least 1 parent living in metropolitan Boston (the Home Allergens and Asthma Study). RESULTS: In a multivariate analysis, infants whose parents reported exposure to mice in the household had nearly twice the odds of developing any wheeze in the first year of life as children without exposure (odds ratio [OR], 1.83; 95% confidence interval [CI], 1.14-2.95; P = .01). Other variables associated with wheeze in the first year of life included low birth weight (OR, 1.77; 95% CI, 1.06-2.95; P = .03), having at least 1 lower respiratory tract illness (OR, 5.59; 95% CI, 3.46-9.04; P < .001), exposure to high levels of endotoxin at age 2 to 3 months (fourth quartile compared with first quartile: OR, 2.32; 95% CI, 1.19-4.54; P = .01), and exposure to cockroach allergen of 0.05 U/g of dust or more at age 2 to 3 months (OR, 1.83; 95% CI, 1.09-3.08; P = .02). CONCLUSION: Among children with a parental history of asthma or allergies, exposure to mice is associated with wheeze in the first year of life, independent of other factors.

Allergens↗

Recovery of metabolic acidosis in term infants with postasphyxial hypoxic-ischemic encephalopathy.

AIMS: To describe the base deficit (BD) values and the rate of postnatal recovery of the BD of infants with hypoxic ischemic encephalopathy due to intrapartum asphyxia; and to explore the relationships between the rate of recovery of BD, severe adverse outcome and different time patterns (acute total vs prolonged partial) of asphyxia. METHODS: Clinical and laboratory data were collected from the neonatal period (n = 244) and outcome data to a minimal age of 1 y (n = 218). Rates of recovery of BD were described in four 60 min blocks of time. The values of rate of recovery were compared between the outcome groups, ignoring correlation structure within subjects and with adjustment by the generalized estimating equations method. RESULTS: The BD normalized within 4 h of birth in all but 9 of 244 infants. The rates of recovery of BD in infants with good and severe adverse outcome respectively were 0.11 [95% confidence interval (95% CI) 0.07, 0.14] and 0.09 (95% CI 0.07, 0.12) mmol l(-1) min(-1) over the first 4 h after birth. The rates of recovery were similar with or without buffer therapy, and after acute near-total and prolonged partial asphyxia. CONCLUSION: The BD in the great majority of infants with severe intrapartum asphyxia normalizes within 4 h of birth. The BD recovery rate of infants with adverse outcomes was similar to those with relatively good outcome. The different time patterns of asphyxial episode were not associated with differential recovery profiles.

Acidosis↗

Female sterilization: can the woman who will seek reversal be identified prospectively?

Demographic socio-economic and decision-making aspects of sterilization and reversal of sterilization were compared in a group of 103 women requesting reversal (RR) and 117 women about to undergo sterilization (S), to determine the practicality of identifying in advance the woman likely to request reversal. The willingness of patients to pay for these procedures and the ethical implications of these decisions were also examined. RR were younger at the first relationship, birth of first child and birth of last child. There were no differences (RR vs S) between the number of full-term pregnancies, living children and therapeutic abortions. The timing of sterilization (puerperal versus interval) did not influence the decision to be reversed. The level of education, partner's level of education and mean family income were lower in the group requesting reversal. Multiple regression analysis revealed three characteristics which were most discriminatory: youth at first birth; lack of spousal support; and failure to choose 'family complete' as a reason for sterilization. The predictability was not strong enough to provide an accurate assessment of the individual woman. RR were of significantly lower socio-economic standing but were more likely to be prepared to pay a large sum of money for the reversal. The ethical implications of this finding are discussed.

Adult↗

Prolonged QT interval and cardiac arrhythmias in two neonates: sudden infant death syndrome in one case.

Two neonates with arrhythmias and the long QT syndrome are described. The arrhythmias were detected in utero and both infants were apparently well after birth. The first infant, although well, had a bradycardia for the first 9 days of life. A normal heart rate was documented at 10 days but a prolonged QT interval was not appreciated on the ECG. He was discharged from hospital but died suddenly and unexpectedly 3 days later. A post-mortem examination failed to find a cause for his death which therefore fell into the category of the sudden infant death syndrome (SIDS). A retrospective analysis of the perinatal electrocardiogram showed a probable junctional rhythm with 2:1 conduction to the ventricle; the QT interval was prolonged at 0.52 seconds (QTC = 0.63). The second infant had a QT interval of 0.52 seconds (QTC = 0.54) and frequent ventricular premature beats on a 24-hour electrocardiogram. She was treated with propranolol and remains well 2 years later. Sudden infant death has often been described in the siblings of children with the long QT syndrome and one other report described a case of SIDS which was said to have had a prolonged QT interval on the perinatal ECG. This report, however, provides unquestionable evidence, in one case, of an association between the long QT syndrome and SIDS.

Arrhythmias, Cardiac↗

Antiretrovirals for reducing the risk of mother-to-child transmission of HIV infection.

BACKGROUND: At the end of 2000 it was estimated that over 36 million people were living with the human immunodeficiency virus (HIV). This includes 1.4 million children less than 15 years of age. This is one of several reviews assessing the available evidence for preventing mother-to-child transmission of HIV infection. The other reviews will address other interventions, including Caesarean section, breast feeding, vaginal lavage and vitamin A supplementation. OBJECTIVES: To assess which antiretroviral therapies may be effective in decreasing the risk of mother-to-child transmission of HIV infection as well as their effect on neonatal and maternal mortality and morbidity. SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth Group trials register and the Cochrane Controlled Trials Register. We also searched conference abstracts from the International AIDS Conferences and Conference on Retroviruses and Opportunistic Infections. SELECTION CRITERIA: Randomised trials comparing any antiretroviral therapy aimed at decreasing the risk of mother-to-child transmission of HIV infection with placebo or no treatment, or any two or more antiretroviral therapies or regimens aimed at decreasing the risk of mother-to-child transmission of HIV infection. DATA COLLECTION AND ANALYSIS: Two reviewers independently extracted data and assessed trial quality. MAIN RESULTS: Zidovudine monotherapy Any zidovudine regimen versus placebo significantly reduces the risk of mother-to-child transmission (Peto odds ratio (OR) 0.46, 95% confidence interval (CI) 0.35 to 0.60). Zidovudine also appears to decrease the risk of infant death within the first year of birth (OR 0.57, 95% CI 0.38 to 0.85) and the risk of maternal death (OR 0.32, 95% CI 0.16 to 0.66). There is no evidence that zidovudine influences the incidence of premature delivery (OR 0.86, 95% CI 0.57 to 1.29) or low birth weight (OR 0.74, 95% CI 0.53 to 1.04). The risk of transmission using a 'short-short' course of zidovudine (from 35 weeks in pregnancy for the mother and for the baby until 3 days old) was higher than the risk using a 'long-long' course (from 28 weeks in pregnancy for the mother and for the baby until 6 weeks old), (OR 2.55, 95% CI 1.26 to 5.18). However, the effectiveness of the 'long-short' course (from 28 weeks in pregnancy for the mother and for the baby until 3 days old) and the 'short-long' course (from 35 weeks in pregnancy for the mother and for the baby until 6 weeks old) did not differ from that of the 'long-long' course. Nevirapine One large randomised controlled trial demonstrates that nevirapine given to mothers as a single dose at the onset of labour and to babies as a single dose within 72 hours of birth is more effective than an intrapartum and post-partum regimen of zidovudine (OR 0.51, 95% CI 0.33 to 0.79). When nevirapine is given to mothers already receiving standard antiretroviral therapy, however, there appears to be no additional advantage (OR 1.10, 95% CI 0.42 to 2.86). Combination Therapy Preliminary findings of the effect of combination therapy using zidovudine and lamivudine (3TC) suggest a decrease in the risk of transmission when the combination is given during the antenatal and intrapartum period or during the intrapartum and postpartum period compared with placebo. There is no evidence that intrapartum zidovudine and lamivudine alone are sufficient to decrease the risk of transmission compared with placebo. REVIEWER'S CONCLUSIONS: Implications for practice The randomised trials included in this review provide evidence that short course zidovudine and single-dose nevirapine are effective therapies for reducing mother-to-child transmission of HIV. The challenge for low and middle income countries will be to institute this therapy in practice. In industrialised countries practice has already moved on from the current evidence and combination antiretroviral therapy aimed primarily at preventing disease progression in the mother is the standard of care. Implications for research The potential value of nevirapine used for longer durations in breastfeeding populations should be considered as it may further reduce the risk of mother-to-child transmission, particularly if combined with early weaning. On-going evaluation of combination antiretroviral therapy is essential and will have an immediate benefit for countries with the resources to adopt such treatment. The search for effective, affordable, safe and acceptable alternatives to antiretroviral therapy for reducing mother-to-child transmission in resource poor countries should remain on the research agenda.

Anti-HIV Agents↗

Induced and spontaneous abortion in relation to risk of breast cancer (United States).

The relation of induced and spontaneous abortion to the risk of breast cancer is evaluated in a hospital-based case-control interview study conducted in three cities in the United States from 1985 through 1995. Cases were 1,803 women aged 25 to 64 years with newly diagnosed invasive breast cancer; controls were 4,182 women of the same ages admitted for conditions unrelated to reproductive factors. Other breast cancer risk-factors were controlled through multiple logistic regression. The reference for all analyses was women who had never had an abortion, either induced or spontaneous. Among parous women, the relative risk (RR) estimate was 1.1 (95 percent confidence interval [CI] = 0.9-1.5) for induced abortion overall, 1.0 (CI = 0.7-1.4) for abortion before the first birth, and 1.3 (CI = 1.0-1.8) for abortion after at least one birth. Among nulliparous women, the relative risk estimate for induced abortion was 1.3 (CI = 0.9-1.9). There was no trend of increased risk with number of abortions, nor was there consistent evidence of an increased risk in any particular subgroup. Spontaneous abortion was not associated with increased risk of breast cancer, either among nulliparous women or among parous women. These findings provide little support for the hypothesis that induced abortion increases breast cancer risk overall or in particular subgroups.

Abortion, Induced↗

Changing paternity and time since last pregnancy; the impact on pre-eclampsia risk. A study of 547 238 women with and without previous pre-eclampsia.

BACKGROUND: Long time interval between pregnancies has been found to increase the risk of pre-eclampsia in second pregnancy. Our aim was to investigate whether this effect is influenced by a history of pre-eclampsia or a change in paternity. METHODS: We studied 547 238 women with a first and second pregnancy registered in the Medical Birth Registry of Norway, 1967-1998. The relative risk of pre-eclampsia in the second delivery according to time interval between deliveries was estimated as odds ratios (OR) in logistic regression models, controlling for changing paternity, maternal age and calendar time period in women with and without previous pre-eclampsia. RESULTS: A change of paternity for the second pregnancy was associated with a reduced risk of pre-eclampsia after controlling for the time since first delivery (adjusted OR = 0.80, 95% CI : 0.72-0.90), but the interaction between change in paternity and time between deliveries was significant only for women with no previous pre-eclampsia. The interaction between history of pre-eclampsia and time interval between the two deliveries was highly significant, and for women with no previous pre-eclampsia the risk of pre-eclampsia in second pregnancy increased with increasing time interval (for intervals longer than 15 years the adjusted OR was 2.11, 95% CI : 1.75-2.53). For women with previous pre-eclampsia the risk tended to decrease with increasing time interval between deliveries. CONCLUSIONS: The protective impact of a new father for the second pregnancy challenges the hypothesis of primipaternity, and implies that the increase in pre-eclampsia risk ascribed to new father by others is due to insufficient control for interpregnancy interval.

Adult↗

Growth patterns of cardiac structures and changes in systolic time intervals in the newborn and infant. A longitudinal echocardiographic study.

A longitudinal study was undertaken in 21 newborns to determine cardiac growth pattern by echocardiography over the course of the first year of life. Most cardiac structures increased in size as a linear function of age and weight; however, the right ventricular end-diastolic diameter remained unchanged so that the RV/LV ratio decreased as a parabolic function of age. Left and right ventricular systolic time intervals (RVSTI, LVSTI) after birth were also studied. The ratio of left ventricular preejection period (LVPEP) to left ventricular ejection time (LVET) decreased markedly immediately after birth and subsequently remained at a constant mean value (0.30 +/- 0.04) for the rest of the study period. Right ventricular systolic time interval ratios (RVPEP/RVET) decreased rapidly and significantly during the first day of life (from a mean value of 0.39 +/- 0.08 in the first 24 hours to 0.28 +/- 0.05 on the 6th day of life). Constant values of 0.24 +/- 0.03 were found from the 3rd month of life onwards. The decrease in RVPEP/RVET in the first days of life followed a parabolic function reflecting the physiological decrease of pulmonary vascular resistance after birth.

Body Weight↗

Changes in gustatory function during the course of pregnancy and postpartum.

OBJECTIVE: To investigate changes in gustatory function during pregnancy and postpartum. DESIGN: Prospective study. SETTING: Obstetric outpatient clinic, Zurich University Hospital. POPULATION: Forty-four pregnant women, 46 controls. METHODS: A threshold-like measure of gustatory function was obtained for different concentrations of the four basic tastes using 'taste tablets'; subjects were also asked to rate the intensity and pleasantness/unpleasantness of suprathreshold taste solutions. Tests were performed in early pregnancy up to 14 weeks of gestational age, 8-12 weeks after the first and second examination and at least 6 weeks after birth. In parallel, controls were tested four times at intervals of 8-12 weeks. MAIN OUTCOME MEASURES: Gustatory score (number of correctly identified tastes). Results Pregnant subjects exhibited a decreased gustatory function compared with non-pregnant controls, still being present after birth. These 'objective' changes were observed although pregnant women rated the intensity of suprathreshold taste stimuli not significantly different from controls. Pregnant women rated salty stimuli to be more pleasant during the second trimester while they rated the salty stimuli to be less pleasant during the first and third trimester, and after birth. CONCLUSIONS: Pregnancy is accompanied by changes in gustatory function. Decreased gustatory sensitivity may allow pregnant and breastfeeding women to vary their diet in order to consume adequate electrolytes. The discrepancy between 'objective' and 'subjective' findings in gustatory function may relate to changes in central processing of gustatory information during pregnancy.

Adult↗

Induced abortion and breast cancer risk.

Results from case-control studies suggest that induced abortion may be associated with a small increase in risk of breast cancer. While risk estimates from cohort studies have generally not observed such an association, these studies have had limited information regarding abortion and possible confounding variables. Therefore, we conducted a study among a cohort of post-menopausal women from whom detailed information regarding pregnancy outcomes as well as risk factors for breast cancer had been collected. The study sample included 37,247 Iowa Women's Health Study participants, 55-64 years of age at baseline in 1986, who reported no history of breast, or other, cancer (except non-melanoma skin cancer), and for whom information regarding pregnancy outcomes (that is, live birth, stillbirth, spontaneous abortion, ectopic pregnancy or induced abortion) was available. We used linkage with records of the State Health Registry of Iowa, part of the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) program, to estimate the incidence of breast cancer among cohort members through 1995. We calculated age-adjusted relative risks and 95% confidence intervals using Cox proportional hazards regression. Only 653 women (1.8%) reported an induced abortion. The age-adjusted relative risk of breast cancer among women with prior induced abortion compared with those without was 1.1 (95% CI = 0.8-1.6). Relative risks were higher among women whose age at first abortion was less than 20 or at least 30 years, for those whose abortion took place after their first birth or who never gave birth, and for those with early termination (0-2 months). These estimates varied from 1.3-1.7, but the confidence intervals around each were wide. Since most women in this cohort were beyond their reproductive years when abortion became legal in 1973, the low prevalence of induced abortion argues for a cautious interpretation.

Abortion, Induced↗

High and low hemoglobin levels during pregnancy: differential risks for preterm birth and small for gestational age.

OBJECTIVE: To examine the association of maternal hemoglobin during pregnancy with preterm birth and small for gestational age (SGA). METHODS: We performed a retrospective cohort analysis of hemoglobin and birth outcome among 173,031 pregnant women who attended publicly funded health programs in ten states and delivered a liveborn infant at 26-42 weeks' gestation. We defined preterm as less than 37 weeks' gestation and SGA as less than the tenth percentile of a US fetal growth reference. RESULTS: Risk of preterm birth was increased in women with low hemoglobin level in the first and second trimester. The odds ratio (OR) for preterm birth with moderate-to-severe anemia during the first trimester (more than three standard deviations [SD] below reference median hemoglobin, equivalent to less than 95 g/L at 12 weeks' gestation) was 1.68 (95% confidence interval [CI] 1.29, 2. 21). Anemia was not associated with SGA. High hemoglobin level during the first and second trimester was associated with SGA but not preterm birth. The ORs for SGA in women with very high hemoglobin level during the first and second trimester (more than three SDs above reference median hemoglobin, equivalent to greater than 149 g/L at 12 weeks' gestation and greater than 144 g/L at 18 weeks') were 1.27 (95% CI 1.02, 1.58) and 1.79 (95% CI 1.49, 2.15), respectively. CONCLUSION: These data highlight the importance of considering anemia and high hemoglobin level as indicators for adverse pregnancy outcome. An elevated hemoglobin level (greater than 144 g/L) is an indicator for possible pregnancy complications associated with poor plasma volume expansion, and should not be mistaken for good iron status.

Adolescent↗

Comparison of Landim and Africander cattle in southern Mozambique: II. Female fertility, reproduction, and beef offtake.

Fertility and reproductive performance of Landim and Africander females were compared using data collected from 1968 to 1981 at the Chobela Research Station in Mozambique. Breeds were managed together and grouped by age and sex, except when separated for breeding. Traits were relative fertility (probability of fertile females calving from the first breeding season), age at first calving, first calving interval, and subsequent calving intervals. calving rates were tested by x2 procedures with equal expected frequencies in each subclass. The statistical model included breed, the random effect of sire within breed, year-season of birth or calving, and calving group within breed. Landim survivors were more fertile (P < .05) than the Africander ones throughout their recorded lifetimes. Landim females were 1.32 +/- .21 mo (or 3%) younger at first calving and had a 48 +/- 12 d (or 11%) shorter interval between first and second calving than the Africander average of 473 d. When reproductive and growth information were combined to compute an annual index of beef offtake expressed as 18-mo calf yield per unit of dam's weight at first calving, Landim cows annually yielded 30% more calf weight (P < .001) than Africander cows per kilogram of their own body maintenance despite lighter body weights at 18 mo. Superior fertility of Landim females led to greater beef offtake from higher calving rates. Greater fertility and relatively less feed to maintain the reproducing herd are probable mechanisms for a population to adapt to nutrient-limiting environments such as the one in southern Mozambique.

Aging↗