Female Reproductive Structures
Many structures of the body are involved in conceiving a child. These include the ovary, fallopian tubes, and uterus in the pelvis. Also included are glands in the brain that secrete hormones.
When a woman is born, her ovaries contain between one and two million follicles. Each follicle contains a single immature egg (oocyte). These eggs are surrounded by cells that secrete female hormones (estrogen). During a woman's lifetime, the follicles break down and gradually decline in number. Only about 300,000 follicles remain by the time a woman reaches puberty.
At puberty, hormones from the brain stimulate the monthly menstrual cycle to begin. This occurs about every 28 days. Usually, with each cycle, one follicle and egg mature. After about 14 days, ovulation occurs. The mature egg is released from the ovary and enters the nearby fallopian tube. If a woman has sex at this time without using birth control, a sperm may enter the egg. If the egg becomes fertilized by the sperm, it creates an embryo. The embryo passes through the fallopian tube into the uterus (womb).
Memorial Sloan-Kettering Cancer Center fertility specialist Joanne Frankel Kelvin discusses the impact that cancer treatment can have on a woman’s fertility, and how patients can plan a family after treatment.
While the follicles mature, hormones from the ovary cause the lining of the uterus to thicken. This prepares the lining so the embryo can implant or stick to the wall. It also prepares the uterus to support the embryo as it grows. Once implanted, the cells continue to divide, and the embryo becomes a fetus. During the nine months of pregnancy, the uterus expands to hold the growing fetus.
If fertilization does not take place, or if an embryo does not implant in the wall of the uterus, hormone levels from the ovary drop. This causes the lining of the uterus to shed. This bloody discharge is seen each month with menstruation (menstrual period). The cycle then begins again.
Effects of Cancer Treatment on Fertility
Cancer treatment can cause problems in a number of different ways.
- Surgery may require removal of one or more of the parts of the body needed to get pregnant or maintain a pregnancy.
- Radiation therapy to the pelvis and some chemotherapy drugs destroy follicles in the ovary. This may have several effects including:
- Reduction in the number of healthy eggs, making it more difficult to become pregnant
- Temporary cessation of monthly menstrual periods
- Premature (early) menopause with permanent cessation of monthly menstrual periods. With menopause, women also stop ovulating and are not able to become pregnant. Women at risk of premature menopause may not remain fertile for as long as they might have expected.
- Radiation therapy to the pelvis can cause changes in the uterus. As a result, an embryo may not be able to implant in the uterus. Or the uterus may not be able to expand to hold a growing fetus. This can result in complications during pregnancy. Examples are miscarriage, preterm (early) birth, or low-birth-weight babies.
- Surgery or radiation therapy to the brain may affect the body's ability to produce the hormones that stimulate the ovaries each month. As a result, ovulation will not occur.
Not all cancer treatments cause problems with fertility. It depends on:
- Your age
- The number and quality of eggs you have before treatment
- The type of surgery you have
- The type and dose of chemotherapy you receive (Some drugs are more likely to affect ovarian function and fertility than others)
- The dose of radiation you receive and the area of the body that is irradiated (Radiation treatment fields that include reproductive structures may affect fertility)
Because of the many factors involved, it is impossible to predict how your fertility will be affected by your treatment.
Fertile Hope is a national, nonprofit organization dedicated to providing reproductive information, support and hope to cancer patients and survivors whose medical treatments present the risk of infertility. Learn more about your risk for infertility by using Fertile Hope's Risk Calculator.
Although we can not always prevent problems with fertility, there are a number of options available for women who want to parent a child using their own eggs in the future. This is called fertility preservation. To preserve your fertility, you can have your eggs collected before you begin treatment. This procedure is performed by a reproductive endocrinologist. These eggs may be fertilized to create embryos. The embryos or eggs are then frozen and stored. This will increase your chance of being able to conceive a child with your own eggs in the future. Collecting eggs can take anywhere from two to six weeks. The amount of time depends on where you are in your menstrual cycle when you first see the reproductive endocrinologist. This may delay your cancer treatment longer than is safe for you. Speak with your cancer doctor before making a decision about collecting eggs. We hope that the questions and answers below will help you decide if pursuing fertility preservation before your treatment is the right choice for you.
Frequently Asked Questions
The reproductive endocrinologist will review your medical history and perform a physical examination. He or she will perform a transvaginal ultrasound to count the follicles in your ovaries. You will also have some blood tests done. These tests will help determine if you have enough healthy eggs to proceed. The doctor will then discuss your options with you and the likelihood that collecting eggs will be successful. This is based on your age, prior treatment, and medical health. The reproductive endocrinologist will also want to consult with your cancer doctor to make sure it is safe for you to proceed with egg collection.
A financial specialist at the fertility center will review your insurance coverage. He or she will discuss the costs of the medications and treatment. Some centers have a social worker or psychologist who may meet with you. He or she can help you decide if egg collection is right for you. You may also meet with a nurse to teach you more about what is involved.
If you decide to proceed with egg collection, you will be asked to sign some forms. One will ask you to indicate who “owns” the frozen eggs or embryos. You will also be asked about what you plan to do with any that are not used. If you have embryos fertilized with sperm from your partner and you separate, who would “own” the embryos? If you were to die unexpectedly, what would you want to do with your eggs or embryos? Would you want to appoint someone as “owner,” or would you want them to be discarded? These are difficult decisions. It will be helpful to consider them before the visit.
You can find a reproductive endocrinologist through Fertile Hope. Under GEOGRAPHY select state, and under SERVICE select Assisted Reproductive Technology (ART) Clinic.
There are several steps involved in collecting eggs.
- On or around the second day of your period you will start giving yourself daily hormone injections. This medicine stimulates your ovaries to mature more eggs than usual. You will continue this for one to two weeks. Sometimes medicine is given so you do not have to wait for the beginning of your menstrual period to start the injections.
- During the time that you are giving yourself daily injections, you will see your doctor for every day or every other day blood tests and transvaginal ultrasounds. The results will let your doctor know how your body is responding to the injections. Day-to-day changes in the dose of your injection are made based on the results of these tests.
- Once you have enough mature eggs, you will give yourself a different injection to stimulate ovulation. You will be scheduled to have your egg retrieval (collection) about 36 hours after this injection.
- The egg retrieval is an outpatient procedure. It is done using anesthesia so you will be asleep. No surgical incision is needed. The eggs are collected using a very thin needle that is passed through your vagina.
While you are on the hormones, you may feel bloated and nauseated. These symptoms will go away when your hormone levels return to normal. This usually happens within two weeks after your eggs are collected. During this time, you can continue most of your usual activities. However, do not perform any vigorous exercise (for example, jogging). If you are sexually active with a male partner, you must use a barrier contraceptive so you do not get pregnant while you are taking the injections.
The more healthy eggs you collect, the better your chances are of using one of them to have a child. However, each collection requires you to go through a menstrual cycle. If you collect for more than one cycle, you may be delaying your cancer treatment longer than is safe for you. Most patients only collect one cycle before their cancer treatment. Speak with your cancer doctor before deciding to collect a second time.
Collecting eggs can be very expensive. The cost includes many different services and procedures, such as:
- An initial consultation with the reproductive endocrinologist
- Blood tests
- Transvaginal ultrasounds
- Collection of the eggs
- Analysis of the eggs
- Fertilization of the eggs
- Freezing of the embryos or eggs
- Storage of the embryos or eggs
Each fertility center charges different amounts for their services. The total cost of egg collection depends on the center. The cost in the New York area is generally about $9,000 to $10,000. In addition to this are the costs of the medicines you need to inject before egg collection. This is generally $2,500 to $5,000. There is also an annual cost to store the embryos or eggs, and when you are ready to thaw the embryos or eggs and use them there is a cost for this as well.
Lastly, there are other indirect costs to keep in mind. If collecting eggs delays your treatment at all, you may need new blood tests or scans before you start your cancer treatment. Your insurance company may not pay for these extra tests.
Many insurance companies do not cover any or all of the costs associated with collecting eggs. Call your insurance company to find out about your coverage. Explain that your doctor has suggested collection of your eggs because of a cancer diagnosis. Having what is called a letter of medical necessity from your doctor may also help.
You may be able to get financial assistance to help with these costs. The organization Fertile Hope has a program called Sharing Hope that may be able to help.
If you are creating embryos, the collected eggs will be mixed with sperm in a laboratory. This is called in vitro fertilization. One method is to mix the eggs with thousands of sperm, allowing the sperm to enter the eggs on their own. Another method is to inject a single sperm into each egg. This is called intracytoplasmic sperm injection (ICSI). It is done when the sperm count is low or when the sperm are not able to move well or to penetrate the egg. Sperm used to fertilize the eggs are obtained either from your male partner or from a sperm donor. After the eggs are fertilized, they are monitored in the laboratory for three to five days. The embryos are then frozen. This is called embryo cryopreservation. When you are ready to use the embryos, one or two are thawed and transferred into your uterus. Thousands of babies have been born using this technique over the past 25 years.
An alternative to embryo cryopreservation is egg (oocyte) cryopreservation. This involves freezing eggs that have not been fertilized. When you are ready to use them, the eggs are thawed and fertilized with sperm. This newer technology is still considered experimental. This option may be preferred by women who do not have a male partner or donor at this time. It also may be preferred by women who do not want to freeze embryos. Over 900 babies have been born using this technique over the past 10 years.
Whether you decide to freeze embryos or eggs, they will be stored until you are ready to use them. Some embryos and eggs are damaged during the freezing and thawing process. However, no known damage occurs while they are frozen. As far as we know, embryos and eggs can be frozen and stored for as long as you would like.
You may first need hormone injections to prepare your uterus for implantation. If you froze embryos, one or two of these will be thawed. If you froze eggs, some of these will be thawed and fertilized. Eggs may be fertilized using sperm from your male partner or from a sperm donor.
Once your uterus is ready for implantation, you will be scheduled for the embryo transfer. This is an outpatient procedure. Anesthesia or sedation is usually not needed. A very thin, soft catheter is placed through the opening of your uterus. One or two embryos are transferred through this catheter into your uterus.
You will be scheduled to return to the reproductive endocrinologist about one week later for blood tests. If you have a positive pregnancy test, an ultrasound is scheduled several weeks later. It will verify that the embryo has implanted and is growing correctly. If you are pregnant, you will then see an obstetrician.
Your reproductive endocrinologist will discuss your personal chances of success with you. However, the success rates of these procedures vary based on a number of factors, including the following:
- Your age (success rates are higher in women under 35 years of age)
- The health of your partner or donor's sperm
- The experience of the fertility team you are working with
For information on the experience of different fertility centers go to the Society for Assisted Reproductive Technologies and click on “IVF Success Rate Reports.” These statistics are not specific to patients with cancer. However, they can give you some idea of the overall experience of a particular fertility center. Success rates for fresh and frozen embryos are reported separately as a percentage. Both the percentage of pregnancies and live births are also reported since some pregnancies will miscarry. The percentages are based on either of the following:
- The number of cycles of ovarian stimulation used to retrieve eggs
- The number of embryos transferred into the uterus
Two other experimental procedures are available for women who are not able to collect eggs. Both require surgery done under anesthesia. Pieces of the ovary or the entire ovary are removed. The tissue is frozen and stored until you are ready to use it. At that time, the tissue can be re-implanted in your body. As of 2009, very few babies have been born using these techniques. New technologies in the future may allow us to use this tissue more effectively. If you would like to learn more, ask your doctor or nurse to refer you to a reproductive endocrinologist who performs this procedure.
When the pelvis is irradiated, the ovaries may be in the field of treatment. As a result, they will be exposed to radiation. Based on the dose, the radiation can damage some or all of the follicles. Ovarian transposition is an outpatient surgical procedure to move the ovaries outside the field of treatment. It is done using anesthesia so you will be asleep. The surgery is done laparoscopically through several small incisions in your abdominal wall. Even when the ovaries are moved outside of the field of treatment, they may still be exposed to some radiation, and follicles may be damaged. If you will also be getting chemotherapy, this can increase the likelihood that follicles will be destroyed. Because of this risk, you may also want to collect eggs before your treatment in addition to having an ovarian transposition. Doing both will give you the best chance of being able to have a biologic child.
For patients with early-stage gynecologic cancers it may be possible to do limited surgery. This means your doctor may be able to leave one or both of your ovaries and uterus intact. For example, some patients who have early cervical cancer can have their cervix removed while leaving the uterus in place. This would make it possible for you to get pregnant and carry a fetus. This procedure is called a radical trachelectomy. Not all patients are eligible for these limited surgeries. It depends on the location and size of your tumor. Ask your gynecologic surgeon if you are a candidate for one of these limited surgeries.