***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: BACKGROUND To assess the effects of HIV-1 and other sexually transmitted infections on pregnancy , we undertook cross-sectional and prospect i ve studies of a rural population in Rakai district , Ug and a. METHODS 4813 sexually active women aged 15 - 49 years were surveyed to find out the prevalence of pregnancy by interview and selective urinary human chorionic gonadotropin tests . The incidence of recognised conception and frequency of pregnancy loss were assessed by follow-up . Sample s were taken to test for HIV-1 infection , syphilis , and other sexually transmitted diseases . FINDINGS At time of survey 757 ( 21.4 % ) of 3544 women without HIV-1 infection or syphilis were pregnant , compared with 46 ( 14.6 % ) of 316 HIV-1-negative women with active syphilis , 117 ( 14.2 % ) of 823 HIV-1-positive women with no concurrent syphilis , and 11 ( 8.5 % ) of 130 women with both syphilis and HIV-1 infection . The multivariate adjusted odds ratio of pregnancy in HIV-1-infected women was 0.45 ( 95 % CI 0.35 - 0.57 ) ; the odds of pregnancy were low both in HIV-1-infected women without symptoms ( 0.49 [ 0.39 - 0.62 ] ) and in women with symptoms of HIV-1-associated disease ( 0.23 [ 0.11 - 0.48 ] ) . In women with concurrent HIV-1 infection and syphilis the odds ratio was 0.28 ( 0.14 - 0.55 ) . The incidence rate of recognised pregnancy during the prospect i ve follow-up study was lower in HIV-1-positive than in HIV-1-negative women ( 23.5 vs 30.1 per 100 woman-years ; adjusted risk ratio 0.73 [ 0.57 - 0.93 ] ) . Rates of pregnancy loss were higher among HIV-1-infected than uninfected women ( 18.5 vs 12.2 % ; odds ratio 1.50 [ 1.01 - 2.27 ] ) . The prevalence of HIV-1 infection was significantly lower in pregnant than in non-pregnant women ( 13.9 vs 21.3 % ) . INTERPRETATION Pregnancy prevalence is greatly reduced in HIV-1-infected women , owing to lower rates of conception and increased rates of pregnancy loss . HIV-1 surveillance confined to pregnant women underestimates the magnitude of the HIV-1 epidemic in the general population The haematological and clinical effects of medroxyprogesterone acetate in homozygous sickle-cell ( SS ) disease were assessed in a 2-year controlled crossover trial completed by 23 patients .  Haematological indices remained steady during the placebo phase , but during the medroxyprogesterone-acetate phase fetal haemoglobin , total haemoglobin , red-cell mass , and red-cell survival rose significantly , and reticulocytes , irreversibly-sickled-cell counts , and total bilirubin fell significantly . Painful crises were significantly less frequent during the medroxyprogesterone-acetate than the placebo phase . These results are compatible with an inhibition of in-vivo sickling in patients with SS disease  during medroxyprogesterone-acetate treatment . The mechanisms of such an effect require further study Megestrol acetate given orally has been assessed in its effect on sickling in vitro . Per cent sickling rates were reduced by the drug compared to placebo . The results indicate the need for further assessing the clinical advantage of oral progestins in patients with sickle cell disease which may also be relevant to their use as contraceptives Forty-three homozygous ( SS ) female sickle cell anemic patients with a history of at least one painful crisis per month and desiring a reversible contraceptive were administered DMPA/3 months or Microgynon monthly . A third group of 16 surgically sterilized patients served as control . Patients were followed for 1 year to assess possible effects of the contraceptives on the patients ' painful crises . No changes were observed in any of the groups in the hematological parameters . At the end of the study , 70 % of the patients receiving DMPA were pain-free and only 16 % of those still reporting painful crises rated them as intense . Patients receiving Microgynon also had an amelioration of the painful crises , although at a lower rate ; after 12 months , 45.5 % still experienced some crises . Although less marked than in the other groups , 50.5 % of the control patients also reported an improvement of their painful crisis , which may be a result of closer medical care 16 male and 28 female patients experiencing moderately severe pain during episodes of sickle-cell disease at least once in 3 months with little or no fever or exacerbations of jaundice were selected for a cross-over trial of low doses of steriods against saline solution . The patients each completed 4 - 6 months of treatment . All patients were on regular folates and had high or normal serum-iron values . Weights ranged from 24 - 134 pounds and ages from 2 - 35 years . Male patients were r and omly assigned to either testosterone in oil ( 10 mg in 1 ml ) or physiological sodium chloride solution ( 1 ml ) . Females were r and omly assigned to progesterone in oil ( 10 mg in 1 ml ) or physiological saline solution . A score was computed each month reflecting the severity , duration , and frequency of episodes of pain . About 80 % of the individuals on steriods had good responses and about the same proportion of the sodium chloride group had very poor responses . 22 of the original 31 patients stopped taking saline injections after the 1st 2 weeks . The packed-cell volumes in the steroid group rose during the period of steroid injections , while there was no appreciable change in the sodium chloride group . There were no sex differences in the pattern of response and no deleterious side effects were noted 
    Output:
    
The limited available data suggest that DMPA is a safe contraceptive option for women in SS disease .
In addition to providing effective contraception , DMPA may reduce sickle pain crises