On November 12, 2015, 113 women from 28 U.S. states who became unintentionally pregnant after taking the wrongly packaged birth control pills joined together to take pharmaceutical companies to court with huge claims, including the cost of childbirth, support and education. Some state laws require that child support payments include the cost of college. The U.S. is an extremely human rights-based society and they are against abortion, which is probably why they conceive a child and have to give birth. The pharmaceutical company is producing packaging that sells placebo pills with no hormone content 180 degrees upside down from pills with contraceptive effects, so that causes such a large number of unwanted pregnancies. This would be unbelievable if it were in China. Zhang Biyun of the Women’s Department at Guangdong Family Planning Hospital talks about unintended pregnancies, but first we need to understand a concept: the Bill Index, which is the number of unwanted pregnancies that occur per 100 women using a contraceptive method for one year. If the index is 1, it means that if 100 women use a contraceptive method for one year, 1 will have an unwanted pregnancy. The smaller the Bill index, the more effective the method is. The current contraceptive methods include the safety period, condom barrier method, subcutaneous implantation, intrauterine device and sterilization. IUD, sterilization, subcutaneous implantation and COC have a Birr index <1, so they are highly effective contraceptive methods, while safe period contraception, with a Birr index of 14-40, is not advocated because it is unsafe. Here, we talk about oral contraceptives two or three things: 1, oral contraceptives development history of oral contraceptives (combined oral contraceptives, COC) is one of the world's widely used contraceptive methods, by low doses of estrogen and progestin composition of the compound steroid hormone preparations. The current WHO recommendation is for COCs containing ≤35ug of ethinyl estradiol, which has been in development for more than 50 years since the first COC, Enovid, was approved for marketing by the U.S. Food and Drug Administration in 1960. (1) The dose of estrogen was reduced from 150ug in Enovid to 30-35ug or even 20ug. (2) Different types of progestins with more natural progestational properties were discovered and applied: the first generation of progestins with strong androgenic properties are no longer used in clinical practice. The second generation, with higher contraceptive efficacy; the third generation, with stronger ovulation inhibition and almost no androgenic effects compared to the second generation. The new progesterone is similar to the physiological activity of natural progesterone, and has anti-androgenic effects, and even has anti-altocorticoid effects. Therefore, "the shortcomings of the third generation of oral contraceptives have been perfectly overcome because the progestins contained in the previous oral contraceptives have androgen-like side effects and can cause water and sodium retention, and therefore the body may gain weight and fat after long-term use of these oral contraceptives". (3) The COC dosing regimen, from 28 days of natural menstruation to the modern 21 days, is followed by a 7-day hormone-free interval (HFI), which triggers endometrial shedding for withdrawal bleeding through the perceived estrogen-progestin decline in the body. Today, the COC (Eusebio, 24/4 regimen) with a much shorter HFI, containing just 20ug of ethinyl estradiol per tablet, can better inhibit ovulatory disease by reducing fluctuations in hormone levels, thereby reducing the incidence and severity of hormonal withdrawal-related symptoms.2. The types of oral contraceptives currently available, the timing of administration and the response to missed doses commonly used are dexprogesterone (momfoolone), ethinyl estradiol cyproterone acetate (Daing-35), and ethinyl estradiol drospirenone (Ursine and Ursine). Most COCs are administered by starting one tablet daily on days 1-5 of the menstrual cycle and stopping for 4-7 days with vaginal withdrawal bleeding. Contraceptive efficiency can be more than 99%. The main reason for contraceptive failure is irregular dosing or missed doses. The likelihood of pregnancy is greatest when 3 or more pills are missed in a cycle. How to remedy a missed dose? In principle, if you miss more than 12 hours or miss more than 2 pills, you can continue to take the pill routinely and use a barrier contraceptive such as a condom for at least 7 days, or take an emergency contraceptive method to prevent unwanted pregnancy; if there are less than 7 pills left, you can start the next cycle of pills immediately after taking the current cycle routinely. Generally, the pill is taken on the 2nd to 5th day of menstruation and can be added to other contraceptive measures for the first 7 days. Taking the pill on the first day of menstruation will produce the best contraceptive effect.3. There are seven major categories of contraindications to the use of oral contraceptives for COC, including: (1) breastfeeding less than 6 weeks after delivery, non-breastfeeding less than 21 days after delivery, women at risk of combined venous thrombosis, smokers, and those aged >35 years. (2) Cardiovascular disease: coronary artery disease, hypertension, heart valve disease, such as pulmonary hypertension, etc. (3) Rheumatic diseases: positive antiphospholipid antibodies, or unexplained SLE.(4) Neurological diseases: persistent migraine without aura. (5) Inflammatory diseases of the reproductive system: acute chronic pelvic inflammatory disease. (6) Endocrine disease: diabetes mellitus combined with renal or retinal disease or neuropathy, diabetes mellitus combined with other vascular disease, or a history of diabetes mellitus of more than 20 years. (7) Gastrointestinal conditions: viral hepatitis, severe cirrhosis or hepatocellular carcinoma, etc. New short-acting COCs are still the main form of contraception, and in addition to contraceptive use, COCs have a wide range of non-contraceptive uses in the field of gynecological diseases, which are not repeated here. This article is published with permission from Dr. Biyun Zhang.