Wednesday, 24 August 2011
Below is part of the report from an expert group convened recently by the Universal Health Care Study Group of the University of the Philippines Manila:
On Monday, 8 August 2011, 21 experts from diverse scientific fields including biochemistry, physiology, pharmacology, obstetrics and gynecology, reproductive endocrinology and infertility, internal medicine, demography, and public health gathered to examine raging questions on pregnancy and contraception applying scientific and evidence-based analysis.
These are our conclusions:
1. Conception is not an exact scientific term. For some it means implantation; for others it is an event that occurs at some time after fertilization. No one at the meeting equates conception with fertilization.
2. Fertilization encompasses the process of penetration of the egg cell by the sperm cell and the combination of their genetic material to form the fertilized egg or the zygote. The process is estimated to take about 24 hours. At present, there is no accepted laboratory or clinical method of determining if and exactly when natural fertilization has taken place, but we accept that it has occurred after a pregnancy has been detected.
Natural losses occur all the time; 33%-50% of all fertilized eggs never implant without the woman doing or taking anything.
3. All contraceptives, including hormonal contraceptives and IUDs, have been demonstrated by laboratory and clinical studies, to act primarily prior to fertilization. Hormonal contraceptives prevent ovulation and make cervical mucus impenetrable to sperm. Medicated IUDs act like hormonal contraceptives. Copper T IUDs incapacitate sperm and prevent fertilization.
4. The thickening or thinning of the endometrium (inner lining of the uterus) associated with the use of hormonal contraceptives has not been demonstrated to exert contraceptive action, i.e. if ovulation happens and there is fertilization, the developing fertilized egg (blastocyst) will implant and result in a pregnancy (contraceptive failure). In fact, blastocysts have been shown to implant in inhospitable sites without an endometrium, such as in Fallopian tubes.
5. Pregnancy can be detected and established using currently available laboratory and clinical tests – e.g. blood and urine levels of HCG (Human Chorionic Gonadotrophin) and ultrasound – only after implantation of the blastocyst. While there are efforts to study chemical factors associated with fertilization, currently there is no test establishing if and when it occurs.
6. Abortion is the termination of an established pregnancy before fetal viability (the fetus' ability to exist independently of the mother). Aside from the 50% of zygotes that are naturally unable to implant, an additional wastage of about 20% of all fertilized eggs occurs due to spontaneous abortions (miscarriages).
7. Abortifacient drugs have different chemical properties and actions from contraceptives. Abortifacients terminate an established pregnancy, while contraceptives prevent pregnancy by preventing fertilization.
8. Like all medical products and interventions, contraceptives must first be approved for safety and effectiveness by drug regulatory agencies. Like all approved drugs, contraceptives have “side effects” and adverse reactions, which warrant their use based on risk-benefit balance and the principles of Rational Drug Use. Risk-benefit balance also applies when doing nothing or not providing medicines, which can result in greater morbidities and death.
In the case of contraceptives, which are 50-year-old medicines, the Medical Eligibility Criteria (MEC) developed by the WHO is the comprehensive clinicians’ reference guiding the advisability of contraceptives for particular medical conditions.
9. The benefits of the rational use of contraceptives far outweigh the risks. The risk of dying from pregnancy and childbirth complications is high (1 to 2 per 1000 live births, repeated with every pregnancy). Compared to women nonsmokers aged below 35 who use contraceptives, the risk of dying from pregnancy and delivery complications is about 2,700 times higher.
10. The risk of cardiovascular complications from the appropriate use of hormonal contraceptives is low. While the risk for venous thrombo-embolism (blood clotting in the veins) among oral contraceptive users is increased, the risk of dying is low, 900 times lower than the risk of dying from pregnancy and childbirth complications. Heart attack and stroke are also rare in women of reproductive age and occur in women using hormonal contraceptives only in the presence of risk factors –like smoking, hypertension, and diabetes. The MEC will guide providers in handling patients with cardiovascular conditions.
11. The risk of breast cancer from the use of combined hormonal pills (exogenous estrogen or estrogen from external sources) is lower than the risk from prolonged exposure to endogenous estrogens (hormones naturally present in the body). Current users of oral contraceptives have a risk of 1.2 compared to 1.9 among women who had early menarche (first menstruation) and late menopause, and 3.0 among women who had their first child after age 35. The risk of breast cancer from oral contraceptive use also completely disappears after 10 years of discontinuing use.
12. Combined hormonal pills are known to have protective effects against ovarian, endometrial and colorectal cancer.
13. The safety and efficacy of contraceptives which passed the scientific scrutiny of the most stringent drug regulatory agencies, including the US FDA, warranted their inclusion in the WHO's "core list" of Essential Medicines since 1977. The core list enumerates "minimum medicine needs for a basic health care system listing the most efficacious, safe and cost-effective medicines for priority conditions."
14. Contraceptives are included in the Universal Health package of the Department of Health.
15. The use of contraceptives in family planning programs is known to reduce maternal mortality by 35% through the elimination of unintended pregnancy and unsafe induced abortions.