REPRODUCTIVE HEALTH AND THE WORKPLACE

What You Should Know About the Female Reproductive System

To understand how reproductive hazards can affect your reproductive health and ability to have healthy children, it is helpful to understand how the female reproductive system works. Reproductive hazards in the workplace act on the tissues, eggs, and hormones that comprise the intricate female reproductive system.

By knowing how the reproductive system works, you can better protect yourself and your family against hazards, better understand your doctor, what you read, and media reports about reproductive hazards.

The female reproductive tissues

The main reproductive tissues in women are the ovaries, uterus, and fallopian tubes. These tissues are primarily controlled by hormones produced by the brain, the pituitary gland and the ovaries. These hormones also control:

• Menstrual cycles
• Pregnancy
• Breast milk production

Why hormones are important

Female sex hormones called estrogen and progesterone are produced by the ovaries. These hormones are responsible for sexual development and for preparing the uterine wall every month to hold and nourish a fertilized egg during pregnancy. These hormones also contribute to the health of the heart, bones, liver, brain and many other tissues. So, a reproductive hazard that alters your estrogen and progesterone production can also reduce your general health.

About the menstrual cycle

• As girls go through puberty, they begin to have periods (menstruation) and menstrual cycles.
• Each menstrual cycle begins with a few days of menstrual flow. When each new cycle begins, a few new eggs begin to grow in the ovaries.
• After about 2 to 3 weeks, one egg - occasionally more - matures to be released from the ovary (ovulation) into the fallopian tubes, where it might be fertilized by one of the many sperm that may surround it.
• If the egg is not fertilized, it will die and leave the body about 2 weeks later in the woman’s menstrual flow. Then the process begins again with a new menstrual cycle, a new period, and a new crop of growing eggs.
• Women are born with all of the eggs they will ever have. Eggs that are damaged or destroyed cannot be replaced.

What happens when an egg is fertilized

• If the egg is fertilized, the complex process of reproduction continues. The fertilized egg travels for about a week down the fallopian tube to reach the uterus, where it attaches to the uterine wall (endometrium).
• A specialized tissue called the placenta forms between the uterus and the newly developing baby. The placenta transfers oxygen and nutrients from the mother to her baby.
• During the first 3 months of pregnancy (first trimester), the baby's major organs are formed.
• During the remainder of the pregnancy, these organs mature and the baby grows rapidly.