Putting off having babies may be the key cause of the increase in the incidence of endometriosis, a common cause of infertility among women in their late 20s and 30s.

“Two or three generations ago women had babies earlier in life and also had more babies which they mainly breastfed. While pregnant and breast feeding their menstruation cycles were temporarily put on hold and they had no periods. This meant there was less opportunity for a back flow of menstrual blood to cause endometriosis. Today many women put off babies until their 30s so they may have 15 or 20 years with an uninterrupted menstrual cycle which increases their exposure to the risk of a back flow of menstrual blood and developing endometriosis,” says Dr Kelly Loi, of the Health and Fertility Centre for Women at Paragon Medical Centre.

Endometriosis mainly affects women during their reproductive years. It is a condition where cells from the endometrium (the lining the womb) are found outside the womb in the pelvis and around the ovaries and fallopian tubes where they can cause fertility issues as the growths can block the passage of both sperm and eggs. Endometriosis can also take hold almost anywhere on, behind or around the womb: in the peritoneum (the tissue that lines the abdominal wall and surrounds most of the organs in the abdomen), on the bowel and the bladder. It can also develop deep within the muscle wall of the uterus where it is called adenomyosis.

Elaborates Dr Loi, “Endometriosis is neither a contagious infection nor a cancer but the exact cause or causes is not certain. The most likely explanation is that during menstruation some of the blood containing cells from the endometrium flows backwards into the pelvic area via the fallopian tubes. Once in the pelvic area, the cells attach themselves to other organs and begin to grow. With each period more cells from the endometrium enter the pelvic area while those already present are stimulated to grow by the hormonal fluctuations of the menstrual cycle.”

She adds, “Although the cause of endometriosis is not known it often runs in families. Numerous biochemical and immunological changes have been identified in association with endometriosis, but it is unclear which may contribute to endometriosis and which simply result from it.”

Impact of endometriosis on a woman’s fertility

When asked about the impact of endometriosis on a woman’s fertility, Dr Loi says, “Endometriosis can develop on the ovaries where it can form cysts (known as chocolate cysts) as well as in or on the fallopian tubes causing fertility issues as the growths can block the passage of both sperm and eggs. Surgery to diagnose and remove endometriosis ovarian cysts can improve fertility, but repeat surgery is generally not beneficial, and may cause harm by reducing the ovarian reserve.”

Doctors suspect endometriosis if the patient is experiencing painful periods, pelvic pain and/or discomfort and pain during sexual intercourse. Although pelvic pain and painful periods are common with endometriosis, they are not always present and don’t necessarily relate to the severity of the condition. It is the location of cysts and lesions rather than their size which causes pain.

Says Dr Loi, “To check for endometriosis the doctor’s first step will usually be a pelvic exam. During a pelvic exam, the doctor palpates (manually feels) areas in your pelvis for abnormalities, such as cysts on your reproductive organs or adhesions (scar tissue) behind your uterus. However it is often not possible to feel small areas of endometriosis unless they’ve caused a cyst to form. So the doctor’s second step is an ultrasound scan, which is the same sort of scan used to see babies in the womb.”

“Ultrasound scans use high-frequency sound waves to create images of the inside of your body. To capture the images, a device called a transducer is either pressed against the abdomen or inserted into the vagina (transvaginal ultrasound). Both types of ultrasound may be done to get the best view of your reproductive organs. Ultrasound imaging won’t definitively tell the doctor whether endometriosis is present, but it can identify ovarian cysts (endometriomas) and large growths in other areas.”

“To be certain the patient may need to undergo a surgical procedure called a laparoscopy to look inside the abdomen for signs of endometriosis. A laparoscopy requires general anaesthesia. While the patient is under anaesthesia, a tiny incision is made near the navel and a slender viewing instrument, the laparoscope, is inserted to look for endometrial tissue outside the uterus. Samples of suspected endometriosis tissue may be taken for biopsy. Laparoscopy can provide information about the location, extent and size of the endometrial growths to help determine the best treatment options.”

Endometriosis treatments

There are four types of treatment options: contraceptives, gonadotropin-releasing hormone (GnRH) agonists, hormone therapy and surgery.

Combination oral contraceptives and continuous cycle regimen hormonal contraceptives like the progestin-only intrauterine devices Mirena and Jaydess and contraceptive implants are sometimes prescribed for mild to moderate endometriosis. They may reduce or eliminate the pain of endometriosis by helping to control the hormones responsible for the build-up of endometrial tissue each month thus making periods shorter and lighter.

Gonadotropin-releasing hormone (GnRH) agonists stop the production of certain hormones to prevent ovulation, menstruation, and the growth of endometriosis. However this treatment sends the body into a “menopausal” state which causes side effects similar to menopause including hot flashes, tiredness, insomnia, headache, depression, joint and muscle stiffness, bone loss, and vaginal dryness. GnRH agonists, which are injected either monthly or every three months, are usually prescribed for short periods, about six months at a time, with several months between treatments if they are repeated because there is increased risk of heart complications and bone loss when taking them for longer periods. As with all hormonal treatments, endometriosis symptoms return after women stop taking GnRH agonists.

Another hormone therapy, Visanne, an oral progestin medication, also reduces the production of certain hormones associated with menstruation. Most women find they stop menstruating after taking it for a few months so it is effective at reducing period and pelvic pain but as it does not cause the menopausal state associated with GnHR agonists, it can be taken for much longer periods. Over time Visanne not only prevents the spread and growth of lesions and cysts but can actually cause them to shrink. As normal fertility returns within a month or two after one ceases taking Visanne, it is a good option for women who need to control their endometriosis but also hope to get pregnant in the future. Visanne is also often prescribed after women have had surgery to remove endometriosis to ensure it does not return.

Surgery is another option. For women who hope to get pregnant, conservative surgery to remove as much endometriosis as possible while preserving the uterus and ovaries may be required to increase their chances of success. If the endometriosis is causing severe pain surgery may also help to relieve it; however, the endometriosis and the pain may well return unless a hormone treatment such as Visanne is used to control it.

These days surgery is usually done laparoscopically but traditional abdominal surgery may be required for very severe and extensive cases. In laparoscopic surgery, the surgeon makes two small incisions near the navel. A slender viewing instrument (laparoscope) is inserted through one and tiny remotely operated instruments inserted through the other to remove the endometrial tissue.

If pregnancy is the woman’s primary concern assisted reproductive technologies, such as in vitro fertilisation, might be needed aside from conservative surgery. Once the woman has had a baby she can continue to undergo hormonal treatments such as Visanne to manage the endometriosis

A total hysterectomy and bilateral salphingo-oophorectomy (THBSO) may be required in severe cases of endometriosis. A THBSO removes the uterus and cervix as well as both ovaries. A hysterectomy alone is not effective as the oestrogen produced by the ovaries could stimulate any remaining endometriosis and cause pain to persist. As one can’t get pregnant after a hysterectomy it is typically considered a last resort for women in their reproductive years.

If women are experiencing period and or pelvic pain or having difficulty conceiving they should consult their gynaecologist. Early diagnosis and treatment of endometriosis and other causes of pain and infertility is the best way to increase the chances of a successful outcome.

Dr Kelly Loi

Dr Kelly Loi

Dr Kelly Loi graduated from the University of Oxford in the United Kingdom and is a member of the Royal College of Obstetricians and Gynaecologists and fellow of the Academy of Medicine Singapore. Based in Health and Fertility Centre for Women at Paragon Medical Centre, Dr Loi is a fertility specialist who has been caring for obstetrics and gynaecology patients for over 15 years.

Opening photo by Shutterstock

Profile photo of Dr Kelly Loi by Health and Fertility Centre for Women, Singapore