Contraception Today

Abstract

Modern contraceptive methods represent more than a technical advance: they are the instrument of a true social revolution-the "first reproductive revolution" in the history of humanity, an achievement of the second part of the 20th century, when modern, effective methods became available. Today a great diversity of techniques have been made available and-thanks to them, fertility rates have decreased from 5.1 in 1950 to 3.7 in 1990. As a consequence, the growth of human population that had more than tripled, from 1.8 to more than 6 billion in just one century, is today being brought under control. At the turn of the millennium, all over the world, more than 600 million married women are using contraception, with nearly 500 million in developing countries. Among married women, contraceptive use rose in all but two developing countries surveyed more than once since 1990. Among unmarried, sexually active women, it grew in 21 of 25 countries recently surveyed. Hormonal contraception, the best known method, first made available as a daily pill, can today be administered through seven different routes: intramuscularly, intranasally, intrauterus, intravaginally, orally, subcutaneously, and transdermally. In the field of oral contraception, new strategies include further dose reduction, the synthesis of new active molecules, and new administration schedules. A new minipill (progestin-only preparation) containing desogestrel has been recently marketed in a number of countries and is capable of consistently inhibiting ovulation in most women. New contraceptive rings to be inserted in the vagina offer a novel approach by providing a sustained release of steroids and low failure rates. The transdermal route for delivering contraceptive steroids is now established via a contraceptive patch, a spray, or a gel. The intramuscular route has also seen new products with the marketing of improved monthly injectable preparations containing an estrogen and a progestin. After the first device capable of delivering progesterone directly into the uterus was withdrawn, a new system releasing locally 20 microg evonorgestrel is today marketed in a majority of countries with excellent contraceptive and therapeutic performance. Finally, several subcutaneously implanted systems have been developed: contraceptive "rods," where the polymeric matrix is mixed with the steroid and "capsules" made of a hollow polymer tube filled with free steroid crystals. New advances have also been made in nonhormonal intrauterine contraception with the development of "frameless" devices. The HIV/AIDS pandemic forced policy makers to look for ways to protect young people from sexually transmitted diseases as well as from untimely pregnancies. This led to the development of the so-called dual protection method, involving the use of a physical barrier (condom) as well as that of a second, highly effective contraceptive method. More complex is the situation with antifertility vaccines, still at a preliminary stage of development and unlikely to be in widespread use f...

Association between duration of oral contraceptive use and risk of hypertension: A meta‐analysis

“…Oral contraception is an important and widely acceptable contraceptive modality worldwide . Since their introduction in the 1960s, oral contraceptives have developed quickly and been used by an increasing number of individuals.…”

Associations between oral contraceptive use and risks of hypertension and prehypertension in a cross-sectional study of Korean women

“…OCs are an important and widely accepted contraceptive modality worldwide [8]. In Korea, most OCs contain 20–40 mg ethinyl estradiol as the estrogen component in addition to a progestin component.…”

International Union of Basic and Clinical Pharmacology. XCVII. G Protein–Coupled Estrogen Receptor and Its Pharmacologic Modulators

“…Although estrogens are recognized predominantly for their function in female mammalian reproduction and the development of secondary sex characteristics, namely uterine and mammary effects, they also play important roles in almost every physiologic system of the body (Edwards, 2005) in both women and men (Lombardi et al, 2001;Finkelstein et al, 2013). As pharmaceutical targets, estrogens and their varied antagonists have been particularly important in contraception (Benagiano et al, 2006) and breast cancer therapy (Jensen and Jordan, 2003), with an increasing appreciation of their therapeutic value in the nervous (McEwen et al, 2012), immune (Cunningham and Gilkeson, 2011), vascular (Knowlton and Lee, 2012), skeletal (Imai et al, 2013), and endocrine systems . For decades, the actions of estrogen(s) were thought to be mediated by a single estrogen receptor first identified in the 1960s (Jensen and Jacobson, 1962;Jensen and DeSombre, 1973), that is, until the discovery of a second highly homologous estrogen receptor in 1996 (Kuiper et al, 1996), whereupon the first estrogen receptor was renamed estrogen receptor a (ERa) and the new receptor ERb.…”