Nutrition before conception and the outcome of pregnancy.

Close birth spacing increases the risk of miscarriage, congenital malformation and perinatal death because it does not give a mother time to recover from the nutritional depletion caused by the first pregnancy or time to recover a normal hormonal profile before the beginning of the next pregnancy. The placental vitamin pump causes maternal vitamin depletion. Nutritional deficits do more damage to reproduction around the time of conception than later during pregnancy. Vitamin and mineral deficiencies can cause not only direct damage to embryonic development but damage to both male and female germ cells resulting in new mutations before a conception. New mutations can cause pregnancy failure or maldevelopment of the embryo. The realisation that nutritional deficits can be mutagenic opened a new chapter in nutritional science. Some nutrients are antimutagenic and already act as such within the digestive tract, but foods contain many other antimutagenic substances. The juices of many fresh vegetables in particular are antimutagenic.