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R T Ravenholt

Publications and source records attributed to R T Ravenholt.

At least 19 recordsLinked to original sources
PubMed1987

Smoking and radon.

Explore the source record for details and available documents.

Air Pollutants↗
PubMed1978

The role of family planning in recent rapid fertility declines in developing countries.

World Fertility Survey data for ten developing countries are used to examine the respective roles of development and family planning in influencing the regulation of fertility. The findings show that high proportions of women at all socioeconomic levels in the countries studied wanted no more children, including large proportions among rural, poor, and uneducated women with few children. The data also show that despite the limitations of underdevelopment, in countries with strong family planning programs knowledge and use of contraception was high. These findings confirm that there is a large unmet demand for family planning and point to the importance of continued allocation of funds to support service programs.

Adolescent↗
PubMed1976

Endometrial control: a comparative study of three oral contraceptives.

Shortly after completing an OC cycle the relative hormonal deficit caused by discontinuing the hormones results in withdrawal bleeding. Similarly, if one or more oral contraceptive tablets are missed during a cycle, the resulting deficiency may cause breakthrough bleeding. A lower incidence of breakthrough bleeding on the day after one oral contraceptive tablet is missed and later onset of withdrawal bleeding indicate that a particular OC provides better endometrial control. These two measurements are used as indices to compare the endometrial control provided by Ovral, Norinyl 1/50, and Nortestrin 1 in a study of 480 women at the Planned Parenthood Clinic in Seattle during 1974 and 1975. An analysis of the data shows that the normal chance of breakthrough bleeding on a particular day when one oral contraceptive tablet is not missed on the previous day is 0.017, 0.022, and 0.022 for Ovral, Norinyl, Norlestrin users, but the chance on the day after a contraceptive tablet is missed increased by 13 to 16 times for each of the three OCs. Ovral provides more sustained endometrial control than Norinyl and Norlestrin, however, as indicated by its lower probability of breakthrough bleeding on the day a contraceptive tablet is missed and by its later onset of withdrawal bleeding.

Adult↗