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L L Doyle

Publications and source records attributed to L L Doyle.

15 recordsLinked to original sources
PubMed1986

Do the sisters of childbearing teenagers have increased rates of childbearing?

In 1983, 89,000 children were born to United States women aged less than or equal to 16. To reduce teenage fertility rates, public health workers will need to identify teenagers at elevated risk for childbearing. We tested the hypothesis that the sisters of childbearing teenagers may form such a group. We performed an historical cohort study of 3,767 teenagers aged 12-16 years who were enrolled in Arkansas Aid to Families with Dependent Children (AFDC), 1978-81; they had 247 pregnancies. Multivariable log-linear hazard models were used to control and study age, race, number of AFDC-eligibles per household, and county urbanization and family planning services. Teenagers whose sisters bore children had elevated rate ratios (RR) for childbearing (RR = 1.8; 95% Confidence Limits [CL] = 1.2-2.6), as did Blacks (RR = 3.1; 95% CL = 2.0-4.8), and members of households with more than nine AFDC-eligibles (RR = 1.7; 95% CL = 1.1-2.6). Because they may have elevated childbearing rates, and would be easy to contact, the sisters of pregnant teenagers could form an important target population for family planning efforts.

Adolescent↗
PubMed1975

Hormone-releasing silicone-rubber intrauterine contraceptive devices. Effect of incorporation of various compounds on intrauterine contraceptive devices in rats.

Intrauterine devices (IUD's) containing 0, 5, or 10 per cent by weight of progesterone, melengestrol acetate (MGA), norethindrone, norgestrel, medroxyprogesterone acetate, isoxsuprine, or R2323 or wound with fine copper wire were placed in one or both horns of cycling female rats. All the progestins improved retention of the silicone-rubber IUD's to some degree. The effects of these compounds on the estrous cycle, mating, ovulation, fertilization, tubal transport, and implantation varied among the compounds. Effects were local or systemic, depending upon the amount and the drug. Uterine motility studies showed clearly that 5 per cent MGA decreased uterine motility; however, no consistent results could be obtained using the other compounds in the same in vivo system.

Acetates↗
PubMed1975

Hormone-releasing silastic intrauterine devices: effect or provera-releasing intrauterine devices on two species of primates.

Silastic intrauterine contraceptive devices (IUDs) 13 mm long and 1.07 mm in diameter could be inserted easily into patas monkey uteri which, like human uteri, expelled them. Addition of 10% Provera to these devices did not reduce the expulsion rate significantly in our study. Control devices had no effect on cycle length in rhesus monkeys. After insertion, the active IUDs frequently caused a delay in onset of menstruation; however, cycles did occur with the device in situ, and normal-length cycles were resumed following removal of the device. A short period of rapid release (almost 35% of the total amount) of Provera from the device was followed by a longer period of sustained release of low levels of the hormone. Even 9 mug/day were sufficient to maintain a decidual reaction in the endometrium of the rhesus monkey. The drug could not be detected in the blood stream at 3,6, or 12 hours in patas monkeys or at 1 or 2 months in rhesus monkeys and so may never have reached the systemic circulation. Devices currently under study in baboons catain Provera or one of three other steroids to determine whether these compounds improve retention rates as well as meet the other two criteria set for the ideal IUD incorporation, for unless we meet this first criterion we can never achieve, let alone test, the others.

Animals↗