***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Abstract Objective : To estimate the association between maternal age and fetal death ( spontaneous abortion , ectopic pregnancy , stillbirth ) , taking into account a woman 's reproductive history . Design : Prospect i ve register linkage study . Subjects : All women with a reproductive outcome ( live birth , stillbirth , spontaneous abortion leading to admission to hospital , induced abortion , ectopic pregnancy , or hydatidiform mole ) in Denmark from 1978 to 1992 ; a total of 634 272 women and 1 221 546 pregnancy outcomes . Main outcome measures : Age related risk of fetal loss , ectopic pregnancy , and stillbirth , and age related risk of spontaneous abortion stratified according to parity and previous spontaneous abortions . Results : Overall , 13.5 % of the pregnancies intended to be carried to term ended with fetal loss . At age 42 years , more than half of such pregnancies result ed in fetal loss . The risk of a spontaneous abortion was 8.9 % in women aged 20–24 years and 74.7 % in those aged 45 years or more . High maternal age was a significant risk factor for spontaneous abortion irrespective of the number of previous miscarriages , parity , or calendar period . The risk of an ectopic pregnancy and stillbirth also increased with increasing maternal age . Conclusions : Fetal loss is high in women in their late 30s or older , irrespective of reproductive history . This should be taken into consideration in pregnancy planning and counselling Some fraction of any cohort of fetuses alive at a given gestational age will ultimately die before birth . The residual prospect i ve risk of stillbirth as a function of gestational age was calculated from records of the New York City Department of Health covering 370,051 reported births between 1987–1989 , including 2454 stillbirths . In the general population , the prospect i ve risk of stillbirth at 26 weeks was one in 150 and , because the time distributions of live births and stillbirths were not proportionate , the risk changed with gestational age . By 40 weeks ' gestation , it was one in 475 , rising progressively thereafter to one in 375 at 43 weeks . The prospect i ve risk of stillbirth was elevated in certain ethnic groups and increased significantly with advanced maternal age , multiple gestation , and lack of prenatal care . The prospect i ve risk of stillbirth is an important consideration in decisions regarding timing of delivery Recent evidence suggests that conditional cash transfer programs for schooling are effective in raising school enrollment and attendance . However , there is also reason to believe that such programs can affect other outcomes , such as the sexual behavior of their young beneficiaries .  Zomba Cash Transfer Program is a r and omized , ongoing conditional cash transfer intervention targeting young women in Malawi that provides incentives ( in the form of school fees and cash transfers ) to current schoolgirls and recent dropouts to stay in or return to school . An average offer of US$ 10/month conditional on satisfactory school attendance – plus direct payment of secondary school fees – led to significant declines in early marriage , teenage pregnancy , and self-reported sexual activity among program beneficiaries after just one year of program implementation . For program beneficiaries who were out of school at baseline , the probability of getting married and becoming pregnant declined by more than 40 percent and 30 percent , respectively . In addition , the incidence of the onset of sexual activity was 38 percent lower among all program beneficiaries than the control group . Overall , these results suggest that conditional cash transfer programs not only serve as useful tools for improving school attendance , but may also reduce sexual activity , teen pregnancy , and early marriage To test the effectiveness of a special health care program for adolescent mothers ( 17 years old or younger ) and their infants , 243 mother-infant pairs were r and omly assigned to one of two groups . All of the mothers were unwed , on Medicaid , and black . The control group received routine well-baby care . The experimental group received routine care and services that included rigorous follow-up , discussion s with the mother about her plans for return to school and use of family planning methods , and extra health teaching . The dropout rate in the experimental group ( 60 % ) was significantly less after 18 months than the control group ( 82 % ) . In spite of the high dropout rate , 91 % of the mothers were located for the 18 month follow-up interview . The repeat pregnancy rate in the experimental group was 12 % after 18 months , and 28 % in the control group . There was no significant difference in the percentage returning to school . After 12 months , the infants in the experimental group were more likely to be fully immunized ( 33 % ) than the infants in the control group ( 18 % ) . Mothers in the special care program who continued to attend clinic used the emergency room less than the mothers who continued to attend in the control group . These results suggest that a comprehensive health care program is one way to bring about better outcomes for both adolescent mothers and their infants OBJECTIVES This study assessed the effects of the Safe Date s program on the primary and secondary prevention of  adolescent dating violence .  METHODS Fourteen schools were r and omly allocated to treatment conditions .  Eighty percent ( n=1886 ) of the eighth and ninth grade rs in a rural county completed baseline question naires , and 1700 ( 90 % ) completed follow-up question naires . RESULTS Treatment and control groups were comparable at baseline . In the full sample at follow-up , less psychological abuse , sexual violence , and violence perpetrated against the current dating partner were reported in treatment than in control schools . In a sub sample of adolescents reporting no dating violence at baseline ( a primary prevention sub sample ) , there was less initiation of psychological abuse in treatment than in control schools . In a sub sample of adolescents reporting dating violence at baseline ( a secondary prevention sub sample ) , there was less psychological abuse and sexual violence perpetration reported at follow-up in treatment than in control schools . Most program effects were explained by changes in dating violence norms , gender stereotyping , and awareness of services . CONCLUSIONS The Safe Date s program shows promise for preventing dating violence among adolescents Abstract Objective : To determine whether a theoretically based sex education programme for adolescents ( SHARE ) delivered by teachers reduced unsafe sexual intercourse compared with current practice . Design : Cluster r and omised trial with follow up two years after baseline ( six months after intervention ) . A process evaluation investigated the delivery of sex education and broader features of each school . Setting : Twenty five secondary schools in east Scotl and . Participants : 8430 pupils aged 13 - 15 years ; 7616 completed the baseline question naire and 5854 completed the two year follow up question naire . Intervention : SHARE programme ( intervention group ) versus existing sex education ( control programme ) . Main outcome measures : Self reported exposure to sexually transmitted disease , use of condoms and contraceptives at first and most recent sexual intercourse , and unwanted pregnancies . Results : When the intervention group was compared with the conventional sex education group in an intention to treat analysis there were no differences in sexual activity or sexual risk taking by the age of 16 years . However , those in the intervention group reported less regret of first sexual intercourse with most recent partner ( young men 9.9 % difference , 95 % confidence interval −18.7 to −1.0 ; young women 7.7 % difference , −16.6 to 1.2 ) . Pupils evaluated the intervention programme more positively , and their knowledge of sexual health improved . Lack of behavioural effect could not be linked to differential quality of delivery of intervention . Conclusions : Compared with conventional sex education this specially design ed intervention did not reduce sexual risk taking in adolescents OBJECTIVE To determine whether the addition of a parental monitoring intervention ( Informed Parents and Children Together [ ImPACT ] ) alone or with " boosters " could enhance ( either broaden or sustain or both ) the effect of a small group , face-to-face adolescent risk reduction intervention Focus on Kids ( FOK ) . METHODS A longitudinal , r and omized , community-based cohort study was conducted of 35 low-income , community-based , in-town setting s. A total of 817 black youths aged 12 to 16 years at baseline were studied . After completion of baseline measures , youths were r and omized to receive a face-to-face intervention alone ( FOK only ) , a face-to-face intervention and a parental monitoring intervention ( FOK plus ImPACT ) , or both of the above plus boosters ( FOK plus ImPACT plus boosters ) .  Risk and protective behaviors were assessed at 6 and 12 months after intervention . RESULTS At 6 months ' follow-up , youths in families that were assigned to FOK plus ImPACT reported significantly lower rates of sexual intercourse , sex without a condom , alcohol use , and cigarette use and marginally lower rates of " risky sexual behavior " compared with youths in families that were assigned to FOK only . At 12 months after intervention , rates of alcohol and marijuana use were significantly lower and cigarette use and overall risk intention were marginally lower among FOK plus ImPACT youths compared with FOK only youths . With regard to the boosters delivered at 7 and 10 months , 2 risk behaviors -- use of crack/cocaine and drug selling -- were significantly lower among the youths who were assigned to receive the additional boosters compared with youths without the boosters . The rates of the other risk behaviors and intentions did not differ significantly . CONCLUSIONS The results of this r and omized , controlled trial indicate that the inclusion of a parental monitoring intervention affords additional protection from involvement in adolescent risk behaviors 6 and 12 months later compared with the provision of an intervention that targets adolescents only . At the same time , the results of the present study do not provide sufficient evidence that booster sessions further improve targeted behaviors enough to include them in a combined parent and youth intervention BACKGROUND Maternal obesity and diabetes are both associated with increased risk of congenital central nervous system ( CNS ) malformations in the offspring and may share a common underlying mechanism . Our objective was to evaluate whether gestational diabetes influenced the association of prepregnancy maternal obesity and risks for CNS birth defects . METHODS This Texas population -based case-control study evaluated births occurring January 1997 through June 2001 . Data came from structured telephone interviews .  Cases ( n=477 ) were mothers of offspring with anencephaly ( n=120 ) , spina bifida ( n=184 ) , holoprosencephaly ( n=49 ) , or isolated hydrocephaly ( n=124 ) . Controls ( n=497 ) were mothers of live infants without abnormalities r and omly selected from the same hospitals as cases . Response rates were approximately 60 % for both cases and controls . We evaluated maternal obesity ( body mass index > or = 30.0 kg/m ) and risks for CNS birth defects , as well as whether gestational diabetes influenced the risks . RESULTS After adjusting for maternal ethnicity , age , education , smoking , alcohol use , and periconceptional vitamin use , obese women had substantially increased risks of delivering offspring with anencephaly ( odds ratio=2.3 ; 95 % confidence interval=1.2 - 4.3 ) , spina bifida ( 2.8 ; 1.7 - 4.5 ) , or isolated hydrocephaly ( 2.7 ; 1.5 - 5.0 ) , but not holoprosencephaly ( 1.4 ; 0.5 - 3.8 ) . Odds ratios were higher for the joint effects of maternal obesity and gestational diabetes , with evidence for interaction on a multiplicative scale . CONCLUSIONS Maternal obesity and gestational diabetes may increase the risk of CNS birth defects through shared causal mechanisms Since 1975 the Rome Microcythaemia Centre has carried out every year , under the auspices of the health authorities of the Latium region , a screening of thalassaemics among intermediate schoolchildren of Latium . From these campaigns , knowledge about thalassaemias among the young adult population has grown which , in its turn , has result ed in screening of these young adults . Through screening in schools between 1975 and 1982 , of 289 763 students examined , 6838 thalassaemics were identified , 6045 of whom were beta- or delta beta-thalassaemics . The total number of young thalassaemics who are identified at present in the Centre through screenings of schoolchildren and young adults is about 3300 per year . Furthermore , from January 1980 to April 1983 , 110 prospect i ve couples of child-bearing age at risk ( 94 of whom originated from Latium ) were identified at the Centre , and five homozygous fetuses ( three of which originated from Latium ) were diagnosed . These data derive from an area in which the frequency of thalassaemia is only 2.4 % , and they show that the programme in Latium for the prevention of Mediterranean anaemia has been successful OBJECTIVE : The aim of this study was to investigate the influence of maternal age on perinatal and obstetric outcome in women aged 40–44 years and those 45 years or older and to estimate whether adverse outcome was related to intercurrent illness and pregnancy complications . METHODS : National prospect i ve ,  population  -based ,  cohort study in women aged 40–44 years and those 45 years or older and in a control group of women aged 20–29 years who delivered during the period 1987–2001 .  Adjusted odds ratios ( OR ) were calculated after adjustments for significant malformations , maternal pre-existing diseases , and smoking . Main outcome measures were perinatal mortality , intrauterine fetal 
    Output:
    
Results Comprehensive interventions can prevent first pregnancy in adolescence by 15 % and repeat adolescent pregnancy by 37 % .
Appropriate birth spacing ( 18 - 24 months from birth to next pregnancy compared to short intervals < 6 months ) can significantly lower maternal mortality , preterm births , stillbirths , low birth weight and early neonatal deaths .