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PubMed2006

Is small for gestational age a marker of future fetal survival in utero?

OBJECTIVE: We sought to assess whether small for gestational age is a risk factor for stillbirth of a subsequent sibling. METHODS: The Missouri maternally linked cohort data set, containing data on births from 1978 through 1997, was used. We identified the study group (women who delivered a SGA infant in the first pregnancy) and a comparison group (women who delivered a non-SGA infant in their first pregnancy) and compared the outcome (stillbirth) in the second pregnancy between both groups. RESULTS: We analyzed information on the first and second pregnancies of 402,015 women (43,549 [10.8%] in the study arm and 358,466 [89.2%] in the comparison arm). Of the 1,883 cases of stillbirth in the second pregnancy, 314 cases occurred in mothers with a history of SGA (stillbirth rate 7.2/1,000) and 1,569 in the comparison group (stillbirth rate 4.4/1,000), P < .001. The adjusted risk of stillbirth was 60% higher in women with a prior SGA (odds ratio [OR] 1.6, 95% confidence interval [CI] 1.4-1.8). The risk for stillbirth in the second pregnancy increased with decreasing gestational age at birth of the SGA infant in the first pregnancy (term: OR 1.4, 95% CI 1.2-1.6; preterm: OR 2.8, 95% CI 2.0-3.8; and very preterm: OR 4.2, 95% CI 2.4-7.3), P for trend < .001. CONCLUSION: Small for gestational age is a marker for subsequent stillbirth, and the risk rises with decreasing gestational age of the SGA birth. This information is potentially useful for counseling parents of SGA infants. LEVEL OF EVIDENCE: II-2.

Adult↗
PubMed2000

Risk of spontaneous abortion following induced abortion is only increased with short interpregnancy interval.

We set out to study the risk of spontaneous abortion following a first trimester induced abortion as a function of the interpregnancy interval between two pregnancies. The cohort study is based on the following databases: Danish national registries: the Medical Birth Registry (MBR), the Hospital Discharge Registry (HDR), and the induced Abortion Registry (IAR). All primigravid women in the time period from 1980 to 1982 were identified in the MBR, the HDR and the IAR. A total of 15 727 women who terminated the pregnancy with a first trimester induced abortion were selected as the induced abortion cohort, and 46 026 women who did not terminate the pregnancy with an induced abortion constituted the control cohort. By register linkage all subsequent pregnancies which were not terminated by induced abortion were identified from 1980 to 1994. Only women who had a non-terminated pregnancy following the index pregnancy were selected. Women whose first pregnancy was terminated following a first trimester induced abortion had a risk of spontaneous abortion of 11.0% vs. 9.4% in the control cohort. This relative difference of 1.17 was not statistically significant in logistic regression analyses. An increased risk was only found for women who had an interpregnancy interval of less than 3 months (OR=4.06, 95% C.I.=1.98-8.31). The abortion method, vacuum aspiration with dilatation or evacuation with dilatation did not modify this elevated risk. Overall the study did not show an increased risk of spontaneous abortion following one or more induced abortions, except for women with a short interpregnancy interval between an induced abortion and a subsequent pregnancy. We recommend women who have a first trimester induced abortion be advised to wait at least 3-6 months before trying to become pregnant again.

Journal Article↗
PubMed1993

Physiologic differences between twin and single born beef calves in the first two days of life.

Behavioral observations and hematological, serum biochemical and blood gas measurements were made on 8 naturally occurring twin calves during the first 48 hours of life. These values were compared to similar measurements collected from 30 single born calves, born under the same calving conditions. All calves survived to at least 3 weeks of age without physically detectable disease. Although the gestational age of the twins and singles were not different, the twins had a lower mean birth weight. Calving difficulty score, time interval to standing and time interval to nursing were not different between the 2 groups. Twin calves had significantly lower rectal temperatures, arterial oxygen tensions and blood glucose concentrations than the single calves through the first 12 hours of life. Hct, Hgb concentration, and RBC were lower in twin calves throughout the 48 hour period. The N:L ratio was lower in the twins at birth. Mean serum IgG1 concentrations were lower in twins only at 24 hours whereas IgM concentrations were lower at both 24 and 48 hours in twins. Serum chemistry value differences between twin and single calves were most numerous at 24 hours of age when serum proteins, urea nitrogen, total bilirubin, sodium, chloride, and total calcium concentrations were higher in the twins and serum phosphorus concentration was lower in the twins.

Animals↗
PubMed2000

Euro-Growth references on increments in length, weight, and head and arm circumferences during the first 3 years of life. Euro-Growth Study Group.

BACKGROUND: Reliable assessment of growth performance of infants and young children requires reference data increments. Available increment references are based on data fitted to mathematical models, a process that diminishes variation in increment values. METHODS: Fully longitudinal data from the multicenter Euro-Growth Study (21 study sites: n = 2145 children) were used to develop sex-specific percentiles for increments in length, weight, and head and mid-upper arm circumferences for selected intervals during the first 36 months of life. Increments (per unit of time) were calculated for 2-, 3- and 6-month intervals from birth to 12 months of age and for 6-month intervals from 12 to 36 months of age. Weight increments were also calculated for 1-month intervals from birth to 6 months of age. The influence of sex, mid-parental height, and study site was determined using analysis of covariance. Comparison with other references was accomplished using percentile values. RESULTS: Mean and standard deviation values as well as selected percentiles (P; P3, P5, P10, P25, P50, P75, P90, P95, and P97) of increments are presented. Length increments of boys were higher than those of girls until 5 months of age but tended to be lower thereafter. Weight increments of boys were higher until 9 months of age. Sex, mid-parental height, and study site explained only between 2% and 13% of the variances of increments. Mean increments were comparable but P10 and P90 substantially differed from published data. CONCLUSIONS: The new Euro-Growth references for increments in length, weight, and head and mid-upper arm circumferences provide tools for health workers that should be useful in screening for adequacy of growth during the first 3 years of life.

Age Factors↗
PubMed2002

Buccal versus intravaginal misoprostol administration for cervical ripening.

OBJECTIVE: The purpose of this study was to compare the efficacy of misoprostol that is administered in the buccal pouch with the intravaginal route of administration. STUDY DESIGN: One hundred fifty-seven pregnant women with a singleton live gestation, Bishop score of <7, estimated fetal weight of <4500 g, and gestational age of >24 weeks were randomized to receive misoprostol that would be placed either in the buccal pouch or vagina every 6 hours. In the buccal group, after the first 2 doses of 200 microg, the dose was increased to 300 microg for the duration of the study (up to a total of 1600 microg). In the vaginal group, after the first 2 doses of 50 microg, the dose was increased to 100 microg for the duration of the study (up to a total of 500 microg). The primary outcome variable was the interval from the first dose to vaginal delivery. Power calculations indicated the need to enroll 71 patients in each arm of the study, which would allow for the detection of a 4-hour reduction in vaginal birth interval for buccal misoprostol. RESULTS: The hours from drug administration to vaginal delivery were similar between the buccal and vaginal groups (23.5 +/- 20.8 hours versus 21.3 +/- 13.4 hours), respectively. Thirty-five women (63%) versus 34 women (67%) delivered vaginally within 24 hours (P = not significant). The incidence of tachysystole was higher in the buccal group, 28 occurrences (38%) versus 15 occurrences (19%; P =.01). CONCLUSION: Buccal misoprostol is effective for cervical ripening but results in a higher incidence of tachysystole than does intravaginal administration.

Administration, Buccal↗
PubMed1980

Reproduction and population growth in free-ranging mantled howling monkeys.

Free-ranging mantled howling monkey (Alouatta palliata Gray) females experienced a regular estrus cycle averaging 16.3 days, demonstrated sexual skin changes, and participated in multiple matings before becoming pregnant. Gestation averaged 186 days. The average interval between births was 22.5 months. Sexual maturity occurred at approximately 36 and 42 months for females and males, respectively. Female age at first birth was about 3 1/2 years. Births were scattered during some years and clustered during others. The age, rank, and parity of the females affected infant survival. More female than male infants survived to one year of age. Increased population size was the result of immigration rather than births.

Age Factors↗
PubMed2002

Rehospitalization for neonatal dehydration: a nested case-control study.

OBJECTIVES: To determine the incidence of neonatal dehydration leading to rehospitalization, whether clinical and health services data could predict its occurrence, and the outcome of dehydrated infants. METHODS: We employed a retrospective case-control design nested within a cohort of 51 383 newborns weighing 2000 g or more, with a gestational age of 36 weeks or more born at 11 Kaiser Permanente hospitals during 1995 and 1996. Cases were 110 infants who were rehospitalized within 15 days of discharge with dehydration, and who either had 12% or greater weight loss or a serum sodium level of 150 mEq/L or greater. Controls were 402 randomly selected infants. We reviewed subjects' paper medical records and telephoned their families at 24 to 36 months of age to ascertain neurological outcomes. RESULTS: Rehospitalization for dehydration occurred in 2.1 per 1000 live births (95% confidence interval [CI], 1.8-2.6). Among vaginal births, the most important risk factors were being born of a first-time mother (adjusted odds ratio [AOR], 5.5; 95% CI, 3.1-9.6); exclusive breastfeeding (AOR, 11.2; 95% CI, 3.9-32.6); maternal age equal to or older than 35 years (AOR, 3.0; 95% CI, 1.5-6.0); and gestational age younger than 39 weeks (AOR, 2.0, 95% CI, 1.2-3.5). Among cesarean births, having a birth hospitalization length of stay less than 48 hours was associated with dehydration (odds ratio [OR], 14.8; 95% CI, 1.4-154.1). Adherence to the American Academy of Pediatrics follow-up guideline did not decrease risk of readmission. Among surviving infants, 1 of 110 cases and 12 of 400 controls had evidence of possible neurological problems 24 to 36 months after discharge (P =.3). No cases of limb gangrene, amputation, or intracranial infarction occurred. CONCLUSIONS: In this population with good access to medical care, serious sequelae of neonatal dehydration are rare. Interventions to decrease the frequency of neonatal dehydration should focus on first-time mothers and those who breastfeed exclusively.

Birth Weight↗
PubMed2000

Association of menstrual and reproductive factors with breast cancer risk: results from the Shanghai Breast Cancer Study.

The incidence of breast cancer among women in Shanghai, a traditionally low-risk population, has increased substantially over the past 20 years. To evaluate the association of menstrual and reproductive factors with breast cancer risk and the influence of these factors on the temporal trend of breast cancer incidence, we analyzed data from the Shanghai Breast Cancer Study, a population-based case-control study of breast cancer recently completed among Chinese women in urban Shanghai. In-person interviews were completed for 1,459 women newly diagnosed with breast cancer between ages 25 and 64 and for 1,556 controls frequency-matched to cases by age. Unconditional logistic regression was employed to estimate adjusted odds ratios (ORs) and 95% confidence intervals (CIs) related to menstrual and reproductive factors. Earlier menarcheal age, nulliparity, and later age at first live birth were associated with increased risk of breast cancer among both pre- and post-menopausal women, while never having breast-fed and later age at menopause were associated with elevated risk only among post-menopausal women. Among controls, 32% of younger women (</=40 years) and 24% of older women (>40 years) reported starting menarche at age of 13 or younger, and this factor contributed to 44% of cases diagnosed among younger women and 26% to 28% of cases in older women. Older age at first live birth or at menopause explained a considerable portion of cases diagnosed in older, but not younger, women. Our study suggests that the changes in menstrual and reproductive patterns among women in Shanghai have contributed to the recent increase in breast cancer incidence, particularly among younger women.

Adult↗
PubMed1995

International renal-cell cancer study. V. Reproductive factors, gynecologic operations and exogenous hormones.

The relationships between reproductive factors, exogenous hormones and renal-cell cancer were examined in an international, multicenter, population-based, case-control study undertaken in 1989-1991. Data from 5 centers situated in Australia, Denmark, Germany, Sweden and the United States included for analysis 608 women with renal-cell cancer and 766 female controls. A significant trend in risk (p = 0.002) was associated with number of births, with an 80% excess risk for 6 or more births [RR = 1.8, 95% confidence interval (CI) = 1.1 to 2.9] compared with one birth. A decreasing risk was seen for increasing age at first birth, although this was confounded by body-mass index and number of births. A suggestive reduction of risk was also seen for increasing age at menarche. Age at menopause was unrelated to risk of renal-cell cancer. An increased risk was observed for women having had both a hysterectomy and an oophorectomy. Use of oral contraceptives in non-smoking women reduced the risk of renal-cell cancer (RR = 0.5, 95% CI = 0.4 to 0.8); this reduction increased with longer duration of use. No association was observed for estrogen replacement therapy. Our results indicate that certain hormonal and reproductive variables may be related to risk of renal-cell cancer and deserve further investigation, both epidemiologically and experimentally.

Adult↗
PubMed1980

Maternal behavior during breast- and bottle-feeding.

Filmed records of an entire feeding session of a population of breast-and bottle-fed human infants were made at approximately 1-month intervals. The occurence of maternal and infant behavior is related to the infant's birth weight during the first week of life only in bottle-fed infants; the greater the mother's response, the less the small infant consumes. There are clear behavioral differences between bottle- and breast-feeding which stem from inherent characteristics of the technique of feeding. Breast-feeding allows the infant to have more control during the feed, whereas in the bottle-feeding, the mother has more control. This concept of control is discussed in terms of its implications for somatic growth and the development of obesity in relation to the advice and training of health professionals.

Birth Weight↗
PubMed1991

Synaptogenesis in the rat suprachiasmatic nucleus: a light microscopic immunocytochemical survey.

MabQ155, a monoclonal antibody against synaptophysin, has been used to conduct a light microscopic survey of synaptogenesis in the suprachiasmatic nucleus of the perinatal rat. Synaptophysin is an integral component of synaptic vesicle membranes which is expressed in growth cones and growth cone filopodia as well as in mature synapses. With the light microscope, mabQ155 immunoreactivity in growth cones can be distinguished from that in presynaptic terminals on the basis of the size of immunoreactive puncta. The current study presents a qualitative and quantitative analysis of synaptogenesis from the day of birth (P0) to postnatal day 10 (P10). In our quantitative analysis we have used daily intervals during the first postnatal week, distinguished between growth cones and presynaptic terminals, and divided the suprachiasmatic nucleus into sampling regions that are related to the progress of synaptogenesis. Our data demonstrate regional differences in synaptogenesis within the suprachiasmatic nucleus (SCN), document the temporal progression from the penetration of growth cones to the appearance of mature synapses, and provide information about gradients of synaptogenesis in the nucleus during development.

Aging↗
PubMed2000

Reproduction in women reporting chronic musculoskeletal disorders.

UNLABELLED: The present population based study assessed aspects of female health as a part of a national cardiovascular screening program in 40-42 year old women in the Sor-Trondelag county. Fertility, events related to the menstrual cycle, reproduction, and the use of contraceptive methods in women reporting musculoskeletal diseases (MSD) were compared to women without these disorders (references). A higher proportion of women with MSD reported subfertility. No significant difference in mean age of menarche or menstrual cycling pattern was found, however women reporting MSD had significantly more often metrorrhagia than references. Mother's age at birth of the first and last child differed from references only in two of the patient groups, and interval between pregnancies was longer in women with MSD. Women with MSD more often chose sterilisation as a contraceptive method. CONCLUSION: Reproduction was altered in women with MSD. It remains to elucidate the interrelationship between rheumatic disorders and gynecological dysfunction.

Adult↗
PubMed2005

The use of urine LH detection kits to time intrauterine insemination with donor sperm.

BACKGROUND: The study was carried out to determine the most likely time of day for the onset of the LH surge as detected using urine LH dipsticks, and to calculate the optimum time interval from the onset of the LH surge to intrauterine insemination (IUI). METHODS: A prospective study of 1540 cycles of IUI with donor sperm at Cleveland Fertility Centre, Middlesbrough, between June 1990 and February 2004. Only 951 cycles (where a positive urine LH dipstick result was immediately preceded by a negative result) were included in our study. To determine the best time interval between the onset of the LH surge and IUI, women were divided into five subgroups according to the positive urine test-IUI time interval and the pregnancy rate and live birth rate per cycle were calculated for each group. RESULTS: The first positive test was most frequently (44.5%) found at lunch-time (11:00-15:00). The live birth per cycle achieved was 5.6% when the insemination was performed 18-23 h from the first detection of the LH surge, and 11.7% when it was performed between 24 and 42 h. The live birth rate declined to 6.5% when IUI was performed later than that. Overall, no significant differences were discovered in live birth or pregnancy rate when insemination was performed at any of the time points between 18 and 53 h. CONCLUSION: Our study suggested that lunch-time is the best time to check for the LH surge using urine dipsticks and insemination at any time between 18 and 53 h after the onset of the surge will produce optimal results.

Adult↗
PubMed2000

Interventions to prevent vertical transmission of HIV-1: effect on viral detection rate in early infant samples.

OBJECTIVE: To determine whether mode of delivery or the use of maternal or neonatal antiretroviral prophylaxis influence the age when HIV-1 can first be detected in infected infants, particularly the probability of detection at birth. METHODS: In a collaboration between four multicentre studies, data on 422 HIV-1 infected infants who were assessed by HIV-1 DNA PCR or cell culture before 14 days of age were analysed. Weibull mixture models were used to estimate the cumulative proportion of infants with detectable levels of HIV-1 according to use of maternal/neonatal antiretroviral therapy (mainly zidovudine monotherapy) and mode of delivery. RESULTS: HIV-1 was detected in 162 infants (38%) when they were first tested, at a median age of 2 days. At birth, it was estimated that 36% [95% confidence interval (CI), 31-41%] of infants have levels of virus that can be detected by DNA PCR or cell culture. This percentage was not associated with either mode of delivery (35% for vaginal delivery versus 40% for cesarean section delivery; P = 0.4) or the use of maternal or neonatal antiretroviral prophylaxis. Among infants with undetectable levels of HIV-1 at birth, the median time to viral detectability was estimated to be 14.8 days (95% CI, 12.9-16.8 days). This time was increased by 15% (95% CI, -11 to 48%; P = 0.3) among infants who were exposed to antiretroviral therapy postnatally compared with infants who were not exposed. No effect was observed for mode of delivery. CONCLUSIONS: The outcome of an early virological test for HIV-1 is thought to be related directly to the timing of transmission and cesarean section delivery primarily reduces the risk of intrapartum transmission. The absence of an association between mode of delivery and viral detectability at birth was therefore unexpected. There was no evidence that foetal or neonatal exposure to prophylactic zidovudine delays substantially the diagnosis of infection, although this cannot be inferred for combination antiretroviral therapy.

Age Factors↗
PubMed2006

Risk factors for hormone receptor-defined breast cancer in postmenopausal women.

The effect of classic breast cancer risk factors on hormone receptor-defined breast cancer is not fully clarified. We explored these associations in a Swedish population-based study. Postmenopausal women ages 50 to 74 years, diagnosed with invasive breast cancer during 1993 to 1995, were compared with 3,065 age frequency-matched controls. We identified 332 estrogen receptor (ER-) and progesterone receptor (PR-) negative, 286 ER+PR-, 71 ER-PR+, 1,165 ER+PR+, and 789 tumors with unknown receptor status. Unconditional logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals (95% CI). Women ages >or=30 years, compared with those ages 20 to 24 years at first birth, were at an increased risk of ER+PR+ tumors (OR, 1.5; 95% CI, 1.2-1.8) but not ER-PR- tumors (OR, 1.1; 95% CI, 0.8-1.6). Women who gained >or=30 kg in weight during adulthood had an approximately 3-fold increased relative risk of ER+PR+ tumors (OR, 2.7; 95% CI, 1.9-3.8), but no risk increase of ER-PR- tumors (OR, 1.0; 95% CI, 0.5-2.1), compared with women who gained <10 kg. Compared with never users, women who used menopausal estrogen-progestin therapy for at least 5 years were at increased risk of ER+PR+ tumors (OR, 3.0; 95% CI, 2.1-4.1) but not ER-PR- tumors (OR, 1.3; 95% CI, 0.7-2.5). In conclusion, other risk factors were similarly related to breast cancer regardless of receptor status, but high age at first birth, substantial weight gain in adult age, and use of menopausal estrogen-progestin therapy were more strongly related to receptor-positive breast cancer than receptor-negative breast cancer.

Aged↗
PubMed1977

Rodent brain growth stages: an analytical review.

Study of data in the literature on rat and mouse brain growth from birth to weaning reveals a stagewise growth in average brain weight. Rapid growth occurs in the intervals between days 0-6, 8-12, and 17-23 after birth. Slow growth periods then lie in the intervals 6-8, 12-17, and after 23 days. The first slow growth period is signalled by events occurring at its end: substantial acceleration of synthesis of RNA, DNA, protein, and myelin. The second slow growth period is characterized by at least a 3-day interval during which there is very little increase in average brain weight compared with what occurs just before and just after that period; the correlation among 12 studies is highly significant. Implications are discussed for cross-species' extrapolation of findings about brain development.

Age Factors↗
PubMed1985

Risk factors for benign breast disease and their relation with breast cancer risk. Pooled information from epidemiologic studies.

Information from published case-control studies on benign breast disease was pooled using standard statistical methods to obtain single, overall risk estimates. This analysis showed that higher socio-economic status (pooled relative risk, RR = 1.24, 95% confidence interval, CI = 1.13-1.37), later menopause (pooled RR = 1.87, 95%, CI = 1.67-2.11) and late age at first birth (pooled RR = 1.30, 95%, CI = 1.13-1.50) were associated with an increased risk of benign breast disease, whereas an apparent protection was given by greater body mass index (pooled RR = 0.58, 95%, CI = 0.50-0.67) and the use of oral contraceptives (pooled RR = 0.75, 95%, CI = 0.67-0.83). The role of these factors did not appear to be materially different in the various histopathologic categories considered, although available information allowed only a general distinction between breast dysplasia (fibrocystic disease) and benign tumors, chiefly fibroadenoma. In conclusion, the general evidence from published studies indicates that benign breast lumps appear to share a number of important risk factors with breast cancer.

Adolescent↗
PubMed2006

Relationship between blood pressure, cerebral electrical activity, cerebral fractional oxygen extraction, and peripheral blood flow in very low birth weight newborn infants.

There is uncertainty about the level of systemic blood pressure required to maintain adequate cerebral oxygen delivery and organ integrity. This prospective, observational study on 35 very low birth weight infants aimed to determine the mean blood pressure (MBP) below which cerebral electrical activity, peripheral blood flow (PBF), and cerebral fractional oxygen extraction (CFOE) are abnormal. Digital EEG, recorded every day on the first 4 d after birth, were analyzed a) by automatic spectral analysis, b) by manual measurement of interburst interval, and c) qualitatively. CFOE and PBF measurements were performed using near-infrared spectroscopy and venous occlusion. MBP was measured using arterial catheters. The median (range) of MBP recorded was 32 mm Hg (16-46). The EEG became abnormal at MBP levels below 23 mm Hg: a) the relative power of the delta (0.5-3.5 Hz) frequency band was decreased, b) interburst intervals were prolonged, and c) all four qualitatively abnormal EEG (low amplitude and prolonged interburst intervals) from four different patients were recorded below this MBP level. The only abnormally high CFOE was measured at MBP of 20 mm Hg. PBF decreased at MBP levels between 23 and 33 mm Hg. None of the infants in this study developed cystic periventricular leukomalacia. One infant (MBP, 22 mm Hg) developed ventricular dilatation after intraventricular hemorrhage. The EEG and CFOE remained normal at MBP levels above 23 mm Hg. It would appear that cerebral perfusion is probably maintained at MBP levels above 23 mm Hg.

Blood Pressure↗