Infertility is defined as the inability to conceive and carry a pregnancy to completion after one year of trying. There are varying causes of infertility. One-third of the time, infertility may be attributed to a problem with the woman’s reproductive system. Another third of the time, the cause may be related to a male partner’s sperm quality. Sometimes, though, no cause can be found, or it can be attributed to a combination of factors.
In order for natural pregnancy to occur, a woman’s body must release a healthy egg from the ovary. Once out of the ovary, the egg travels to the fallopian tube, where it is fertilized by sperm. The fertilized egg then travels to the uterus, develops further, and then implants into this organ’s internal wall. Problems with any part of this process can lead to infertility.
Our fertility experts at locations including NYU Langone’s Fertility Center and NYU Langone Reproductive Specialists of New York determine the best individualized treatments for infertility in women. The length of time to wait before an infertility evaluation is determined largely by a woman’s age. Women younger than 35 are encouraged to schedule a consultation with one of our specialists after 6 to 12 months of unsuccessful pregnancy attempts. Women older than age 35 are often better served after three to six months without conception, or sooner if preliminary testing reveals a problem with the ovaries, eggs, fallopian tubes, uterus or, if a male partner is involved, the quality of his sperm. Experts can evaluate both men and women to determine the best strategies to achieve pregnancy.
Because of a worldwide trend to postpone pregnancy, age is now the leading cause of infertility in women. This is because the number and quality of a woman’s eggs decrease as she ages, most dramatically beginning at age 35. Another common contributor to infertility is anovulation, or the inability to release an egg from the ovary. Anovulation can be caused by a relatively common hormone disorder called polycystic ovary syndrome (PCOS). Other causes of anovulation include obesity, extreme thinness or anorexia, excessive exercise, hormone imbalances, or hypothalamic amenorrhea, the latter due to the lack of proper brain signaling necessary to induce ovulation. Without ovulation, no egg is released to be fertilized and implanted in the uterus.
In couples with a male partner, infertility can be caused by problems of the male reproductive system, including a reduced number of sperm in the semen, also known as low sperm concentration, decreased sperm motility, or movement, or no sperm production at all, which is known as azoospermia. The latter can be due to problems with sperm production, or it can be caused by a blockage within the reproductive tract that interferes with normal ejaculation. Infertility in men is typically assessed using a semen analysis, in which a semen sample is provided by the male partner and analyzed in a laboratory.
Other common factors contributing to infertility in women include pelvic adhesions and damaged fallopian tubes. Either one of these conditions can prevent sperm and egg from meeting within the reproductive tract or a fertilized egg from travelling to the uterus. A severely damaged fallopian tube—one that becomes fluid-filled, partially or completely blocked, and swollen—is known as a hydrosalpinx. One or both fallopian tubes can become damaged. Having a hydrosalpinx increases the risk of ectopic pregnancy, in which an embryo implants outside the uterus.
Causes of fallopian tube damage include sexually transmitted infections (STIs) such as chlamydia or gonorrhea, or pelvic diseases, such as endometriosis. In endometriosis, tissue from the uterine cavity spreads outside that organ causing tissue damage, pelvic adhesions, or ovarian cysts, known as endometriomas. All of these changes can interfere with conception.
Problems within the uterus can also impair the ability to conceive by interfering with the implantation process of an embryo. They include fibroids, which are noncancerous growths originating in the organ’s muscle, endometrial polyps, and intrauterine adhesions, also known as synechiae, a condition in which bands of scar tissue form within the endometrial cavity.
Other uterine problems include congenital malformations of the uterus and less commonly, the vagina, such as a septum, in which the uterus, the vagina, or both are partitioned; a bicornuate—or heart-shaped—uterus; a unicornuate, or half uterus; or a didelphic, or duplicated uterus. Some congenital anomalies can be surgically corrected.
Our experts specialize in surgery for such anomalies and the management of recurrent miscarriage, in which a woman does not carry a pregnancy to term.
Other factors that can lower a woman’s chances of conception include poor diet, cigarette smoking or using smokeless tobacco products, stress, and excessive alcohol consumption.
Our fertility experts help women and men explore causes of infertility and treatment options and provide support throughout the process. At the initial consultation, your doctor takes a careful medical history, asking whether you have any chronic illnesses. He or she then performs physical and pelvic ultrasound examinations and typically orders tests.
A female pelvic and ultrasound exam is commonly performed during the initial consultation. These allow our doctors to assess the uterus, fallopian tubes, and ovaries.
Our doctors evaluate the size of the uterus and look for fibroids, scarring and polyps within the endometrial lining, and any uterine anomalies. They also assess the fallopian tubes for swelling or enlargement and check the ovaries’ health and function.
To determine how the ovaries are performing relative to a woman’s age, doctors assess their size and volume. They also perform an antral follicle count, in which the number of resting follicles are assessed to estimate how many eggs a woman has in reserve.
The ovaries are also evaluated for the presence of cysts or tumors. Some ovarian cysts—such as ovarian follicles and corpus luteum—occur naturally during ovulation and don’t require treatment. Other cysts, such as those caused by endometriosis or other benign tumors, such as dermoids, may be discovered. Less commonly, cancerous masses may be diagnosed. All these conditions can have an impact on fertility.
Our doctors are experts in the surgical treatment of benign ovarian processes. If cancer is suspected, NYU Langone surgical oncologists specialize in the management of these conditions.
Measurement of follicle-stimulating hormone, also known as FSH, and anti-Mullerian hormone, also known as AMH, is often done to assess how a woman’s ovaries are functioning relative to her age. Thyroid and, sometimes, the pituitary hormone, prolactin, are tested to determine whether either of these organ systems may be interfering with reproductive function.
Our doctors also measure progesterone levels to determine whether a woman is ovulating on her own. Several other hormones may also be tested, if appropriate.
A hysterogram, also called a hysterosalpingogram, is an X-ray test that checks whether a woman’s fallopian tubes are functional and if the uterus is normally shaped and sized. A saline-infusion sonogram evaluates the uterus for fibroids, polyps, or scar tissue. In a third uterine test known as a FemVue®, the uterus and fallopian tubes are filled with air bubbles which, along with an ultrasound exam, allow the doctor to look for uterine disease or tubal blockage.
If a woman has a male sexual partner, a semen analysis is performed on a collected semen sample. If a man has previously had a vasectomy or is known to have a blockage that prevents sperm from naturally leaving the body, sperm can be extracted directly from the testes. During a semen analysis, the number of sperm present as well as their overall motility, or movement, is determined.
To help prevent the potentially harmful transmission of hereditary conditions, gene-carrier testing for diseases is recommended to identify whether a woman or couple is at risk of passing on certain illnesses.
To ensure the health of women and any resulting pregnancies, our doctors perform testing for STIs, including chlamydia, gonorrhea, hepatitis B and C, human immunodeficiency virus (HIV), human T-cell lymphocyte virus types 1 and 2, and syphilis. Immunity testing for diseases that can affect pregnancy is also performed. These diseases include measles, cytomegalovirus, German measles, varicella (chicken pox), and rubella.
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