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PubMed2001

Serological, colostral and milk responses of cows vaccinated with a single dose of a combined vaccine against rotavirus, coronavirus and Escherichia coli F5 (K99).

Twenty-five Ayrshire/Friesian cows were vaccinated once with a new combined vaccine against rotavirus, coronavirus and Escherichia coli F5 (K99) or given a saline placebo 31 days before the first expected calving date. Blood samples were taken from the cows at intervals from vaccination until seven days after calving and from their calves up to 28 days after birth, and colostrum and milk samples were collected from the cows at intervals for 28 days after calving. There was a significant increase in the mean specific antibody titre against all three antigens in the serum of the vaccinated animals (even in the presence of pre-existing antibody) which was accompanied by increased levels of protective antibodies to rotavirus, coronavirus and E coli F5 (K99) in their colostrum and milk for at least 28 days.

Animals↗
PubMed1994

Human alpha-lactalbumin and bovine beta-lactoglobulin absorption in premature infants.

The absorption of alpha-lactalbumin (ALA) and bovine beta-lactoglobulin (BLG) was investigated in 23 healthy preterm infants with gestational ages of 32 to 36 wk. The concentrations of ALA and BLG in serum after a milk feeding were measured at intervals during the first 8 mo of life. We used a time-resolved fluoroimmunoassay to measure the proteins. Measurable amounts of ALA were found on d 7 after birth, and at 1, 2, 3, 5, and 8 mo in 23 of 23, 13 of 18, 13 of 18, six of 17, eight of 16, and five of 13, respectively, of the infants tested; median serum levels of ALA at the respective ages were 120 (range, 19-2598), 16 (range, 0-177), 5 (range, 0-40), 0 (range 0-3), 0.8 (range 0-38), and 0 (range, 0-22) micrograms/L serum/g ALA given/kg body wt, respectively. The rate of decline in ALA absorption was comparable among the infants. Tests for BLG were begun after the introduction of cow's milk. At 2, 3, 5, and 8 mo of age BLG was detected in two of 7, two of 9, eight of 10, and two of 12, respectively, of the infants tested, where median levels in positive cases were 13, 17, 15, and 3 micrograms/L serum/g BLG given/kg, respectively. The amounts of absorbed ALA and BLG were 10(-5) to 10(-3) of the oral dose. Serum levels of ALA or BLG did not depend on the gestational age of the infant. Few of the infants had any detectable absorption of either protein shortly after weaning.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗
PubMed1992

Management considerations in heifer development and puberty.

Management of replacement beef heifers should focus on factors that enhance physiological processes that promote puberty. Age at puberty is important as a production trait when heifers are bred to calve as 2-yr-olds and in systems that impose restricted breeding periods. Calving by 24 mo of age is necessary to obtain maximum lifetime productivity. Because the reproductive system is the last major organ system to mature, factors that influence puberty are critical. The influence of environment on the sequence of events leading to puberty in the heifer is dictated largely by the nutritional status of the animal and related effects on growth rate and development. Management strategies have been designed to ensure that heifers reach a prebreeding target weight that supports optimum reproductive performance, and consequences of inadequate or excessive development have been evaluated. Those strategies are based on evidence linking postweaning nutritional development with key reproductive events that include age at puberty and first breeding, conception, pregnancy loss, incidence and severity of dystocia, and postpartum interval to estrus. Management alternatives that ultimately affect lifetime productivity and reproductive performance of heifers begin at birth and include decisions that involve growth-promoting implants, creep-feeding, breed type and(or) species, birth date and weaning weight, social interaction, sire selection, and exogenous hormonal treatments to synchronize or induce estrus. Basic and applied future research efforts should converge to match in a realistic manner the production potential of the animal with available resources. Strategies that incorporate consideration of nutrition, genetics, and emerging management techniques will need to be tested to enable producers to make decisions that result in profit. This review evaluates the current status of knowledge relating to management of the replacement beef heifer and serves to stimulate research needed to enhance management techniques to ensure puberty at an optimal age.

Animal Feed↗
PubMed2001

Population-based, case-control study of blood C-peptide level and breast cancer risk.

Insulin resistance has been suggested to be associated with an increased risk of breast cancer. Insulin sensitivity can be measured using blood C-peptide, a marker of insulin secretion. It is thus conceivable that blood C-peptide levels may be associated with breast cancer risk. To evaluate this hypothesis, we analyzed data from a subset (143 case-control pairs matched by age and status of menopause) of women who participated in the Shanghai Breast Cancer Study, a population-based, case-control study conducted in Shanghai during 1996-1998. Fasting blood samples were collected from study subjects to measure C-peptide levels. For cancer patients, the samples were collected before any cancer therapy. Conditional logistic regression was used to estimate adjusted odds ratios and 95% confidence intervals related to C-peptide levels. Breast cancer risk was increased with increasing levels of C-peptide (trend test, P = 0.01), with an odds ratio of 2.7 (95% confidence interval = 1.2-5.9) observed for the highest compared with the lowest tertile of C-peptide concentration after adjusting for body mass index and age at the first live birth. The risk was not altered after fully adjusting for other traditional risk factors for breast cancer. This positive association was observed in both pre and postmenopausal women and regardless of the levels of waist-to-hip ratio or body mass index. The results from this study were consistent with the insulin-resistance hypothesis for breast cancer and suggest that increased levels of C-peptide may contribute to the development of breast cancer.

Adult↗
PubMed1982

[Determination of serum concentrations of aminoglycosides in the monitoring of therapy in neonates. I. Gentamycin].

We studied the serum concentrations of gentamicin by radio-immuno-assay in 22 sick prematures (birth weight 1713 +/- 469 g, prenatal age 33 +/- 3 weeks, postnatal age 12 +/- 9 days) receiving 2.5 mg/kg bid. Bactericidal concentrations were present in 91% but only 50% had normal serum concentrations and gentamicin half-lives. Gentamicin half-life decreased significantly (p less than 0.01) with postnatal age but there was no statistically significant correlation between gentamicin serum concentration and gestational age or birth weight. We therefore recommend 1. gentamicin serum concentrations to be monitored routinely in therapy of prematures especially in the first week of life, 2. to expand the dosage interval up to 18 hours (which is about the threefold half-life) in prematures during the first week of life.

Gentamicins↗
PubMedDate not supplied

Secondary infertility following induced abortion. World Health Organization Task Force on Sequelae of Abortion, special programme of research, development and research training in human reproduction.

Two university centers in Debrecen, Hungary and Seoul, Republic of Korea collaborated in a prospective study of fertility following induced abortion. Conception rates were compared for 30 months among two groups of women whose last pregnancy outcome was either an induced abortion or a live birth. The cumulative life-table pregnancy rates at each six-month interval for the 30 months of the study were similar in the two groups, although the pregnancy rate was higher in Debrecen than in Seoul for both groups, probably reflecting age differences between the two groups. In the first six months of the study, 4 of the 229 pregnancies in the induced abortion group were ectopic, whereas none of the 292 pregnancies in the live birth group were ectopic. Although on the basis of the two populations studied there is no evidence of a reduced ability to conceive following induced abortion, the occurrence of four ectopic pregnancies in the induced abortion group warrants further investigation.

Abortion, Induced↗
PubMed2002

Adverse childhood experiences and risk of paternity in teen pregnancy.

OBJECTIVE: Few studies have investigated risk factors that predispose males to be involved in teen pregnancies. To provide new information on such factors, we examined the relationships of eight common adverse childhood experiences to a male's risk of impregnating a teenager. METHODS: We conducted a retrospective cohort study using questionnaire responses from 7399 men who visited a primary care clinic of a large health maintenance organization in California. Data included age of the youngest female ever impregnated; the man's own age at the time; his history of childhood emotional, physical, or sexual abuse; having a battered mother; parental separation or divorce; and having household members who were substance abusers, mentally ill, or criminals. Odds ratios (ORs) for the risk of involvement in a teen pregnancy were adjusted for age, race, and education. RESULTS: At least one adverse childhood experience was reported by 63% of participants, and 34% had at least two adverse childhood experiences; 19% of men had been involved in a teen pregnancy. Each adverse childhood experience was positively associated with impregnating a teenager, with ORs ranging from 1.2 (sexual abuse) to 1.8 (criminal in home). We found strong graded relationships (P <.001) between the number of adverse childhood experiences and the risk of involvement in a teen pregnancy for each of four birth cohorts during the last century. Compared with males with no adverse childhood experiences, a male with at least five adverse childhood experiences had an OR of 2.6 (95% confidence interval [CI] 2.0, 3.4) for impregnating a teenager. The magnitude of the ORs for the adverse childhood experiences was reduced 64-100% by adjustment for potential intermediate variables (age at first intercourse, number of sexual partners, having a sexually transmitted disease, and alcohol or drug abuse) that also exhibited a strong graded relationship to adverse childhood experiences. CONCLUSION: Adverse childhood experiences have an important relationship to male involvement in teen pregnancy. This relationship has persisted throughout four successive birth cohorts dating back to 1900-1929, suggesting that the effects of adverse childhood experiences transcend changing sexual mores and contraceptive methods. Efforts to prevent teen pregnancy will likely benefit from preventing adverse childhood experiences and their associated effects on male behaviors that might mediate the increased risk of teen pregnancy.

Adolescent↗
PubMed1991

Adverse infant outcomes associated with first-trimester vaginal bleeding.

We assessed the association between first-trimester vaginal bleeding and singleton infant outcomes in a hospital-based population of 11,444 nondiabetic women. Low birth weight (LBW), shortened gestation, LBW at term, and neonatal death occurred more often in women reporting first-trimester bleeding than in those who never bled. These relationships remained statistically significant after adjusting for confounding factors. Women who experienced vaginal bleeding limited to the first trimester (N = 1174) had double the risk of delivering a preterm infant compared with those experiencing no bleeding (adjusted risk ratio = 2.0; 95% confidence interval 1.6-2.5). Bleeding limited to the first trimester was associated with a 1.6-fold risk of delivery of a term LBW infant (95% confidence interval 1.3-2.0). These results suggest that first-trimester vaginal bleeding is an important correlate of adverse infant outcomes.

Adult↗
PubMed2004

Fetal arrhythmias: the Saint-Justine hospital experience.

We intend to review our experience with the investigation and management of foetal arrhythmia on the basis of superior vena cava/ascending aorta (SVC/AA) Doppler flow velocity recordings. Irregular rhythms n = 307. Premature atrial and ventricular contractions were easily identified and generally self-limited in time. Sustained bradycardia n = 19. Four had sinus bradycardia, six presented with blocked atrial bigeminism, three showed 2:1, and five had a complete atrio-ventricular (AV) block. Another foetus that presented with first-degree AV block developed a Luciani-Wenckebach phenomenon 1 week later. These different types of bradycardia were all identified on SVC/AA Doppler recordings. Tachyarrhythmia n = 30. Five types of tachyarrhythmia were observed: Type I: Short ventriculo-atrial (VA) tachycardia (VA < AV), n = 11. Ten foetuses of this group presented a distinctive Doppler flow velocity pattern characterised by 1:1 AV conduction and a tall atrial wave ('a' wave) superimposed on the aortic ejection wave. They were considered to have re-entrant tachycardia through a fast-conducting AV accessory pathway; all 10 responded to digoxin therapy. The eleventh foetus with short VA tachycardia had atrial ectopic tachycardia with AV node dysfunction; he was treated successfully with sotalol. Type II: Long VA tachycardia (VA > AV): n = 8. In seven cases, an 'a' wave of normal amplitude with normal AV time interval could be clearly identified in front of the aortic ejection wave: one foetus in this group was considered to be in sinus tachycardia based on the variability of its heart rate; in another, sudden onset of tachycardia triggered by extrasystoles led to the possibility of permanent junctional reciprocating tachycardia (PJRT). The five other foetuses had atrial ectopic tachycardia. The last foetus presented with AV and VA intervals of the same duration and a heart rate of 210 beats/min; he did not respond either to digoxin or to sotalol, and was found after birth to have PJRT. The drug of first choice in this group was sotalol. Type III: Simultaneous onset of atrial and ventricular contractions: n = 3. These foetuses were classified as junctional ectopic tachycardia. Two responded to amiodarone. The other foetus converted spontaneously to sinus rhythm. Type IV: Flutter: n = 7. All presented with 2:1 AV relationship except one who had a variable block. Digoxin was prescribed as a first choice associated with sotalol in three cases. Conversion to sinus rhythm was documented in all; however, one hydropic foetus with advanced cardiomyopathy died one day after birth. Type V: Ventricular tachycardia: n = 1. This 30-week foetus presented alternance of AV dissociation (atrial rate: 130, ventricular rate: 170 beats/min) and atrial capture (ventricular rate of 138 beats/min). The arrhythmia responded well to propanol, and no recurrence was recorded after birth. Precise prenatal identification of arrhythmia type can be achieved with the SVC/AA Doppler approach. Such information allows for a better management and a rational choice of appropriate anti-arrhythmic drug.

Arrhythmias, Cardiac↗
PubMed1989

Gestational vaginal bleeding and pregnancy outcome.

The relation between vaginal bleeding and pregnancy outcome was examined in a prospective study of 3,531 women seeking prenatal care in New York City from 1975 through 1985. Women were interviewed in the second trimester or later and were followed up at delivery. The frequency of vaginal bleeding during pregnancy was 22%. Few maternal characteristics or exposures were predictive of bleeding, and those that were associated with an increased risk of bleeding were only marginally so. Risk factors included advanced maternal age, previous spontaneous or induced abortion, working during pregnancy, and certain gynecologic conditions (fibroids, cervical inflammation, and ovarian cysts). Severity of bleeding was examined in relation to birth weight and length of gestation at delivery. Light bleeding during pregnancy was not associated with decreased birth weight or with shortened gestation at delivery. Heavy bleeding was associated with a decrease in mean birth weight of about 100 g (p less than 0.05) but was not significantly associated with the risk of low birth weight (odds ratio (OR) = 1.7, 95% confidence interval (CI) 0.9-3.3). Heavy bleeding was associated with preterm delivery among private patients (OR = 6.4, 95% Cl 1.7-23.5) but not public patients (OR = 0.3, 95% Cl 0.1-1.4). First trimester bleeding of any severity was marginally associated with congenital malformations in the offspring (OR = 1.7, 95% Cl 1.0-2.9); the effect was the same for major and minor abnormalities. There was no association between first trimester bleeding and placental complications of pregnancy or the delivery of a stillborn infant.

Adult↗
PubMed1986

On a probability distribution to study the open birth interval and its application.

"A probability distribution for describing the variation in the length of open birth interval regardless of parity has been derived assuming that fecundability varies from female to female and the births are of two types, one which results [in] infant death and the other [which does] not. To get the estimates of the parameters, expressions for the first two moments have been derived. The model has been applied to the data taken from the survey 'Rural Development and Population Growth--A Sample Survey 1978,' conducted under the auspices of the Demographic Research Centre, Banaras Hindu University [India]."

Asia↗
PubMed2002

Effect of exclusive breast-feeding and early solid food avoidance on the incidence of atopic dermatitis in high-risk infants at 1 year of age.

The aim of this study was to assess the preventive effect of exclusive breast-feeding and early solid food avoidance on atopic dermatitis (AD) in infancy. This study is part of a dietary clinical trial in a prospective cohort of healthy term newborns at risk of atopy. It was recommended to breast-feed for at least 4 months and to avoid solid food in the same time-period. Eight hundred and sixty-five infants exclusively breast-fed, and 256 infants partially or exclusively formula-fed, were followed-up until the end of the first year following birth. AD and sensitization to milk and egg were considered as study end-points. The 1-year incidence of AD was compared between the two study groups. Adjusted odds ratios (OR) with 95% confidence intervals (CI) were calculated by multiple logistic regression. The incidence of AD was calculated in relation to age at introduction of solid food and amount of food given. In the breast-fed group, the adjusted OR for AD was 0.47 (95% CI 0.30-0.74). The strongest risk factor was the occurrence of AD in the subject's core family. The risk of infants with AD to be sensitized to milk was four times higher, and to egg eight times higher, than in infants without AD. Age at first introduction of solid food and diversity of solid food showed no effect on AD incidence. We conclude that in infants at atopic risk, exclusive breast-feeding for at least 4 months is effective in preventing AD in the first year of life.

Breast Feeding↗
PubMed2004

The impact of route of delivery and presentation on twin neonatal and infant mortality: a population-based study in the USA, 1995-97.

OBJECTIVE: We examined whether the route of delivery for near-term (> or = 34 weeks' gestation) twins, as candidates for vaginal delivery, affected neonatal and infant mortality rates. We further evaluated whether these mortality rates were modified by fetal presentation. METHODS: A population-based retrospective cohort study based on the matched multiple births data in the USA (1995-97) was performed. Analyses were restricted to non-malformed liveborn twins delivered at (> or = 34 weeks' gestation. Twins with breech-breech and breech-vertex presentations were excluded, since they are not candidates for vaginal delivery. Neonatal mortality rates (death within the first 27 days) and post-neonatal mortality rates (death between 28 and 365 days) per 1000 twin live births, by route of delivery and fetal presentation, were derived. The associations between neonatal mortality, post-neonatal mortality and the route of delivery for vertex-breech versus vertex-vertex presentations were expressed based on relative risks (RR) and 95% confidence intervals (CI) derived from logistic regression models based on the method of generalized estimating equations. RESULTS: Of the 177,622 twins analyzed, 87% (n = 154,531) presented as vertex-vertex. Fifty-five per cent (n = 97,692) of twins were both delivered vaginally, 41% (n = 72,825) were both delivered by Cesarean section and, of the remaining 4% (n = 7,105), the first twin was delivered vaginally and the second by Cesarean section. Twins with vertex-breech presentations delivered by Cesarean-cesarean sections, as well as those with vertex-vertex presentations delivered vaginally, had the lowest neonatal mortality rate (1.6 per 1000 live births). The highest neonatal mortality rate in the vertex-breech pairs occurred with vaginal-Cesarean deliveries (2.7 per 1000 live births). Among twins with vertex-vertex presentations, twins delivered via the vaginal-Cesarean route experienced the highest neonatal mortality (3.8 per 1000 live births). The RR for neonatal mortality in this group was 2.24 (95% CI 1.35, 3.72) compared with twins both delivered vaginally. CONCLUSION: Route of delivery and fetal presentation both confer an impact on twin infant mortality rates. Strategies to reduce discordant routes in complicated vaginal deliveries may lead to improved neonatal survival.

Cohort Studies↗
PubMed2000

Life history and demography of wild moor macaques (Macaca maurus): summary of ten years of observations.

Data on the life history and demography of individual species are indispensable when we discuss social behavior from an evolutionary perspective, and when we attempt to make adequate conservation plans. This is the first report on the life history and demography of moor macaques in their natural habitat. Moor macaques (Macaca maurus) in the Karaenta Nature Reserve, South Sulawesi, Indonesia, have been observed since 1981. Individual identification of group members began in 1988. The size of the study group increased continuously, from 20 to 43, over this 10-year period of observation (1988-1998). The average population growth rate was 8.0%, and 45 births were confirmed during this period. They were categorized as moderately seasonal breeders. Mortality rate within one year after birth was 17.1%. Average inter-birth interval following surviving infants was 24.1 months, while that following early infant death was 15.0 months. As is the case in other species of macaques, males moved between groups while females stayed in their natal groups. Females seemed to exhibit their first perineal swelling at 4-6 years of age, and to have their first infant at 6-7 years. Males left their natal group at 7-9 years. Solitary males were seldom observed around the study group. The late dispersal of males from their natal groups and their infrequent movement between groups contrast with patterns in well-known macaque species such as Japanese macaques. Recently, differences in social characteristics among macaque species have attracted the attention of researchers. Our findings would be useful to further understanding of such social differences.

Animals↗
PubMed1994

Natural interpregnancy intervals of fertile couples: a longitudinal survey of grand grand multiparous women.

OBJECTIVE: To characterize the natural fecundity of grand grand multiparous women (> or = 10 deliveries) in relation to age, number of pregnancies, body mass index, and chronic diseases. DESIGN: A retrospective longitudinal analysis of interpregnancy intervals of married couples who had never used any kind of contraception. PATIENTS, PARTICIPANTS: The interpregnancy intervals (months from delivery or spontaneous abortion to the next conception) of 96 grand grand multiparous women with a total of 1,327 pregnancies were evaluated from the first to the latest pregnancy (14 +/- 1.7; mean +/- SD). Because of the lack of reliable data on conception times, 109 pregnancies had to be excluded. The number of interpregnancy intervals remaining for evaluation was thus 1,218. RESULTS: The mean interpregnancy intervals in the material of 1,218 pregnancies was 8.5 +/- 4.9 months, being significantly shorter after an abortion (5.3 +/- 4.8 months) or stillbirth (6.0 +/- 4.7 months) than after a delivery (8.9 +/- 5.6 months). The interpregnancy interval was significantly longer in women over 30 years of age than in the younger women, approximately 7 months in the latter and exceeding 10 months around the age of 40 years. Body mass index and chronic medical illness did not influence the interpregnancy intervals. The incidence of spontaneous abortions increased after the age of 30 years. It was 6% until 30 years, 10% between 31 and 35 years, and 25% after 40 years. CONCLUSIONS: In this retrospective longitudinal review, the reproductive capacity of fertile couples remains rather sound until premenopausal age. The data suggest that a woman's delivery capacity could be 25 births between 16 and 45 years of age.

Abortion, Induced↗
PubMed1996

Prevalence study of domestic violence victims in an emergency department.

STUDY OBJECTIVE: In 1992, a study of the prevalence and predictors of domestic violence victims among individuals who presented to a major public hospital emergency department was conducted to replicate a study conducted by the authors in the same setting 12 months previously. The second study aimed to investigate more accurately the presentation of current victims of domestic violence to the ED. METHODS: In a retrospective, cross-sectional study, a screening questionnaire was administered to participants to establish the prevalence of a history and current presentation of domestic violence problems among patients who presented to the ED of a major public hospital. The study group comprised a representative sample of 670 male and 553 female adults (older than 16 years) who presented to all sections of a public hospital ED during 53 randomly selected 8-hour nursing shifts over an 8-week period in 1992. RESULTS: The results of the second prevalence study confirmed those of the first study. Of the 1,223 respondents in the study, 15.5% disclosed a history of adult domestic violence (8.5% of men, 23.9% of women). Women were at greater risk than men for abuse as adults (raw relative risk [RR], 3.27; 95% confidence interval [CI], 2.23 to 4.79; RR adjusted for age, history of child abuse, and country of birth, 4.13; CI, 2.86 to 5.95). Women were at greater risk than men for being doubly abused (as a child and as an adult)(raw RR, 2.17; CI, 1.33 to 3.53). The second prevalence study confirmed what had been indicated in the first study: that 2.0% of women who presented to the ED (11.6% of all women with a history of adult domestic violence) were current victims of domestic violence and that these women presented mainly between the hours of 5 pm and 8 am, when no social work services were available for referral of victims. CONCLUSION: These Australian studies support the findings of prevalence studies of domestic violence victims in ED in the United States. The prevalence and risk factors indicate the need for training of physicians and nurses in the ED about domestic violence and for provision of appropriate backup referral services such as after-hours social work services.

Adolescent↗
PubMed2003

Reference values for change in body mass index from birth to 18 years of age.

UNLABELLED: Body mass index (BMI) has become the measure of choice for determination of nutritional status during the paediatric years, as in adults. Recently, several cross-sectional BMI childhood reference values standards have been published. In order precisely to evaluate childhood nutritional interventions, reference values allowing for the evaluation of changes in BMI values are also needed. For the first time, such reference values can be presented based on 3650 longitudinally followed healthy Swedish children born full term. The reference values for the change in BMI are given as the change in BMI standard deviation scores. The reference values are given as means of mathematical functions adjusting for gender, age of the child and the length of the interval between two measurements for interval lengths of 0.25 to 1.0 y before 2 y of age and of 1 to 5 y between birth and 18 y. The usefulness of the reference values is proved by a graph that forms a part of a clinical computer program; the -2 to +2 standard deviation range of the predicted change in BMI can be computed for an individual child and drawn in the graph as an extended support for clinical decision-making. CONCLUSION: For the first time this communication gives access to BMI growth rate values that can be used both in research and in the clinic to evaluate various interventions, be they nutritional, surgical or therapeutic.

Adult↗
PubMed1973

Influence of pregnancy spacing on outcome of pregnancy.

To assess the significance of the length of time between two pregnancies on the outcome of the second we used information collected by the British Perinatal Mortality Survey of 1958. From questionnaires on the 16,994 singleton births in the first week of March 1958 and the 7,117 singleton stillbirths and neonatal deaths in March, April, and May 1958 we abstracted information on the date and outcome of any preceding pregnancy. The interpregnancy interval was taken as the length of time between this preceding pregnancy and the last menstrual period before the index pregnancy. The most important factors influencing pregnancy spacing were outcome of the preceding delivery, social class, and maternal age. When these variables had been taken into account we found that the length of interpregnancy interval had little effect on stillbirth rates. High neonatal death rates, however, occurred when interpregnancy intervals were less than six months (P <0.005), though longer intervals had no significant effects.

Adolescent↗