Changes in the way research ethics was visualised in the wake of the Nuremberg Trials (1946), led to an atmosphere of protectionism of groups deemed to be vulnerable that was often legislated or regulated. This resulted in the relative underrepresentation of women in clinical trials. The position of women in research was further compromised in 1977, when in response to the tragedies resulting from thalidomide and diethylstilbestrol (DES), the United States Food and Drug Administration (FDA) prohibited women of child-bearing years from participation in early stage clinical trials. In practice this ban was often applied very widely to exclude all women. Women, at least those in the child-bearing years, were also deemed unsuitable research subjects due to their fluctuating hormonal levels during the menstrual cycle. However, research has demonstrated significant biological differences between the sexes in rates of susceptibility, symptoms and response to treatment in many major areas of health, including heart disease and some cancers. These exclusions pose a threat to the application of evidence-based medicine to women, and compromise to care offered to both women and men.
Three related targets of MDG5 were adolescent birth rate, contraceptive prevalence and unmet need for family planning (where prevalence+unmet need = total need), which were monitored by the Population Division of the UN Department of Economic and Social Affairs. Contraceptive use was part of Goal 5B (universal access to reproductive health), as Indicator 5.3. The evaluation of MDG5 in 2015 showed that amongst couples usage had increased worldwide from 55% to 64%. with one of the largest increases in Subsaharan Africa (13 to 28%). The corollary, unmet need, declined slightly worldwide (15 to 12%). In 2015 these targets became part of SDG5 (gender equality and empowerment) under Target 5.6: Ensure universal access to sexual and reproductive health and reproductive rights, where Indicator 5.6.1 is the proportion of women aged 15–49 years who make their own informed decisions regarding sexual relations, contraceptive use and reproductive health care (p. 31).
Family planning and birth spacing can influence the nutrition of adolescent girls, women of reproductive age, and women with young children by reducing the number of adverse outcomes associated with pregnancy and abortion. For adolescent girls, in particular, pregnancy is associated with increased risk of birth complications, anemia, hindered linear growth, and loss of educational attainment (8, 107). Delaying early child marriages and providing access to family planning, particularly for young wives, allow girls to achieve their maximum growth potential (8, 142). However, for women with young children, there was scarce evidence from observational studies to suggest that greater birth spacing had any impact on anthropometric status (BMI, weight), micronutrient status (anemia, as well as serum zinc, copper, magnesium, and folate), and maternal mortality outcomes (13, 107, 143–147). Findings were mixed, which was attributed to sample size and other confounding factors such as maternal age, breastfeeding status, and supplementation status (146, 147). The strongest evidence of the impact of birth spacing on women's nutrition was related to increased risk of preterm delivery and maternal anemia in interpregnancy intervals <6 mo (14, 146, 147) and increased risk of pre-eclampsia in intervals >5 y (107).
Consult your health care professional. Women of childbearing age may want to consider taking folic acid supplements to reduce the risk of having a pregnancy affected with neural tube defects. Many women and teenage girls don't get enough calcium or vitamin D, both of which are critical to healthy bones and avoiding osteoporosis. Some people with diabetes appear to benefit from chromium. Vegetarians, especially vegans, may want to consider supplements to obtain nutrients they aren't getting from animal products.