The Fertility Institute of Hawaii, Oahu’s premier infertility clinic in Honolulu, Maui, Hilo, and Kona, evaluates and treats patients in Hawaii and across the Pacific for all possible infertility diagnoses.
What is Infertility?
Infertility is any medical condition that impairs a couple’s ability to conceive and give birth. If you and your partner are having trouble getting pregnant, the best opportunity for evaluation and successful treatment is from a physician with a special interest in the area of infertility. A woman may initially seek treatment help from an obstetrician/gynecologist and a man from a urologist. If treatment does not result in pregnancy, they should consult a Reproductive Endocrinology and Infertility specialist.
Does infertility only happen to women?
While many people associate infertility with women, it actually occurs equally among both women and men. About one-third of all cases can be traced to factors involving women, and one-third to male factors. The remaining cases result from a combination of problems involving both partners or cannot be explained.
Understanding the human reproductive process
Conception and pregnancy depend on complicated relationships between many factors in both women and men. Disruption in any of these processes in either or both partners can affect fertility. For this reason, it is important to understand the normal reproductive functions in both partners.
The Female Reproductive System
Women are born with about 500,000 eggs stored in the ovaries. During her reproductive years, a woman usually releases a single mature egg each month as part of her menstrual cycle. In addition to producing a mature egg, the ovaries produce the female hormones estrogen and progesterone. The eggs develop and mature inside follicles, which are tiny fluid-filled sacs that exist in each ovary. At mid-cycle, one egg is released from a follicle in a process known as ovulation. After the egg travels along one of the fallopian tubes toward the uterus, it is ready for fertilization by the man’s sperm. If a sperm penetrates the egg, fertilization occurs. The fertilized egg then implants in the lining of the uterus, where it gains nourishment as it grows.
The uterus is the muscular organ where a fertilized egg, or embryo, attaches and develops. It is about the size and shape of a pear and is lined with a rich and nourishing mucous membrane called the endometrium. The vagina is the passage from the outside of the body to the cervix, the opening to the uterus.
Normal anatomy and regular menstrual cycles in the female are important factors in establishing fertility. Monthly changes in a woman’s hormone levels control the sequence of events. To better understand the process, it helps to know the menstrual cycle and the hormones involved.
The Menstrual Cycle
The menstrual cycle refers to the maturation and release of an egg and the preparation of the uterus to receive and nurture an embryo. A typical cycle lasts about 28-32 days and is divided into three distinct phases. On the first day of the cycle, when menstruation begins, the uterus sheds its lining from the previous cycle.
Follicular Phase- Day 1 to about Day 13
During the follicular phase, the body releases follicle-stimulating hormone (FSH). FSH stimulates the development of the follicle, which contains the maturing egg. The follicle also secretes estrogen, which produces midcycle changes in the cervical mucus. These changes help prepare the cervical mucus to receive and nourish sperm from the man.
Ovulatory Phase- Around Day 14
The ovulatory phase begins when a hormone called luteinizing hormone (LH) dramatically increases, or surges. LH causes the follicle to break open and release its egg into the fallopian tube. This process, known as ovulation, lasts about 24 hours. Most women do not ovulate exactly on “Day 14”. Some women ovulate earlier, some later, and some never ovulate. A woman’s ovulation pattern can also vary from month to month. A woman may also get her period even if she is not ovulating.
A woman’s fertile time is around midcycle when ovulation occurs, which is on or about the 14th day after the first day of the period. Unlike the rest of the monthly cycle, cervical mucus is receptive to sperm around the time of ovulation. When a couple has intercourse during this time, sperm swim in the cervical mucus. Gradually, sperm swim into the uterus and along the fallopian tube, where the egg and sperm unite. The egg can be fertilized for about 24 hours after it is released from the follicle.
Luteal Phase-Day 15 to about Day 28
After ovulation occurs, the luteal phase begins. During the luteal phase, the follicle that produced the egg becomes a functioning gland called the corpus luteum. The corpus luteum produces progesterone, which prepares the uterus with the rich lining needed for the fertilized egg (embryo) to implant.
The fertilized egg, or embryo, travels back through the fallopian tube toward the uterus. Once in the uterus, the embryo implants into the lining around the 20th day of the cycle. The corpus luteum senses the pregnancy and continues producing progesterone, preserving the uterine lining and pregnancy. If fertilization does not occur, the corpus luteum will cease to function on about day 26. The uterus then breaks down and sheds its lining several days later, and the next menstrual cycle begins.
How to know when ovulation occurs
Several methods can help you estimate when you ovulate. One way is to use a basal body thermometer (BBT) to take the woman’s basal temperature every morning and chart the temperature.
Another way to determine ovulation is to use an ovulation predictor urine test kit or device. This test measures hormone levels in urine and helps the woman determine when she is ovulating during her cycle. Intercourse or insemination can then be scheduled to take advantage of this window of fertility.
The Male Reproductive System
The male reproductive system is also under the influence of hormones and is responsible for producing sperm. In fact, the same hormones that regulate female reproductive functions also regulate the production of sperm in the male. FSH stimulates sperm production, and LH stimulates testosterone production. Testosterone helps maintain sperm production, sexual desire, and male characteristics such as hair growth. Sperm is produced by the testes (or testicles)- glands located in the scrotum. The scrotum protects the testes and maintains a temperature slightly lower than normal body temperature to help sperm develop properly. As sperm are produced, they pass from the testes through the coiled channels of the epididymis, which is an organ that stores and nourishes sperm as they mature.
Once sperm are completely mature (spermatozoa), they move into the vas deferens. This tube connects the epididymis to the seminal vesicles, two pouch-like glands that store mature sperm. The entire process, from sperm formation to maturation, takes about 80 days. However, this process is ongoing, and sperm are produced continuously.
When a man ejaculates (releases fluid from his penis during intercourse), the sperm from the seminal vesicles combine with a thick fluid from the prostate gland to create semen. The fluid (ejaculate) is deposited into the woman’s vagina. Sperm can live 48 –72 hours within the female reproductive tract, retaining the ability to fertilize an egg. This is why sexual intercourse around the time of ovulation is necessary for conception to occur.