From hormones and sexually transmitted diseases to the lining of the uterus, we cover everything you need to know when you're trying to conceive in this A to Z guide on fertility.
This refers to when a woman doesn't ovulate and, therefore, is unable to get pregnant. One of the most common causes of anovulation is Polycystic Ovarian Syndrome; see P. Note: Chronic anovulation is a well-known cause of infertility.
Basal body temperature
Charting your basal body temperature over your menstrual cycle lets you know when you are ovulating so that you can time sex sessions when you're trying for a baby.
Dr Ann Tan, gynaecologist and obstetrician at the Women Fertility & Fetal Centre, explains: "In a fertile woman, there will be low temperature in the first half of the cycle and then the temperature rises and stays elevated in the second half of the cycle."
Cysts on your ovaries
These may affect fertility and your chances of getting pregnant. There are many types of ovarian cysts, each with different causes, and no one knows why they occur, says Dr Christopher Chong, obstetrician and gynaecologist at Gleneagles Hospital.
"In general, doctors will discuss removal of the cyst if the size is above 4cm as these are less likely to resolve," says Dr Chong. "If no surgery is done, the cyst needs to be monitored. Cysts can grow and can burst or twist - both of which can cause severe pain and become an emergency. If the cyst continues to grow, it will occupy more and more of the ovary, and affect fertility."
Donor sperm or egg
If you are undergoing in-vitro fertilisation (IVF), and there are issues with your egg or your hubby's sperm, you might have to look at getting donors involved.
In Singapore, sperm banks are available at some hospitals and clinics. However, there is very limited access to donor eggs and most clinics will ask you to find your own donor, such as a friend or family member. The Ministry of Health also has a list of overseas sperm banks you are allowed to access.
Note: Singapore law states that egg donors cannot be paid for their contribution, although you are allowed to pay for the cost of expenses incurred during this process. And both donors of sperm and eggs have no legal claim to the child if one is born as a result. The couple undergoing fertility treatments is listed as the parents.
This common condition affects about 10 per cent of women and happens when the endometrium is found outside of the womb. Symptoms include painful periods, chronic pelvic pain, pain during sex, heavy or irregular periods, and bowel-related symptoms during your period. However, it's often undiagnosed as many women dismiss severe menstrual pain as just an inconvenience they have to put up with every month.
"When endometriosis affects the ovaries and grows cysts within them, it could reduce a woman's fertility by destroying ovarian tissue, hence eggs,' says Dr Tan. "It can also diminish fertility by causing the fallopian tubes to become kinked or blocked, again reducing the chance of conception."
The fallopian tubes are where your eggs pass through to get from your ovaries to your uterus, so fertilisation may occur. Some women have only one tube; they're either born with it or lost the other one through surgery. If there are no other complications, they are still able to get pregnant.
The issue of infertility pops up when your tubes are blocked. Dr Tan explains: "Any condition that leads to blockage of the fallopian tubes will lead to infertility. For example, endometriosis, pelvic inflammatory disease, tuberculosis, previous appendicitis or other pelvic surgeries."
Some women can't conceive or can't carry a baby to term. In such cases, a gestational carrier - known as a surrogate - may be used.
Note: In Singapore, there are no explicit laws that prohibit surrogacy, but the Ministry of Health's guidelines don't allow fertility clinics to carry out surrogacy arrangements.
"The ovulation hormones are follicle stimulating hormones (FSH), which stimulate egg production, and luteinising hormones (LH), which release the egg," says Dr Chong. "Other common hormones include thyroid hormones and prolactin hormone. High prolactin leads to breast milk production in a non-pregnant woman. If abnormal, it can cause a woman not to ovulate."
In-Vitro Fertilisation (IVF)
IVF is a procedure where the fertilisation process between egg and sperm takes place in a laboratory. The resulting embryos are put back into the woman's uterus, so conception can occur.
Intrauterine insemination (IUI) is another fertility treatment, where sperm is placed inside a woman's uterus, so fertilisation can take place. If sperm issues are the only fertility problem identified, it's usually the process doctors recommend first, before IVF.
While undergoing an IVF cycle, a woman has to inject herself with hormones, sometimes a few times a day.
Ovulation predictor kits, available in pharmacies, help you to identify when you're going to ovulate, and therefore, when you need to have sex in order to get pregnant. This can be done through either urine or saliva tests, and are especially helpful for women with irregular periods.
Lining of your uterus
"The embryo implants itself in the lining of the womb or endometrium," says Dr Tan. "Hence, the lining has to be thick and spongy. It should also have a healthy blood supply to be able to nourish and protect the embryo as it develops into a foetus."
Male factor infertility
Infertility in a couple can be on the part of the woman or the man. For men, the causes of infertility are quite straightforward.
"Male factor infertility is due to poor sperm quality, such as poor motility, too many abnormal sperm or low volume of sperm," says Dr Chong. "It can also be due to erectile problems, sexual problems, and in some, no sperm at all because of blocked ducts or trauma to the testes."
Natural Killer Cells
These are part of your immune system and their job is to attack infections or foreign bodies. However, some women have high levels of these cells, which then 'attack' an embryo when it tries to implant itself or after it has implanted. This results in the absence of a pregnancy - either naturally or via IVF - or a miscarriage in the first trimester.
Women who can't seem to get pregnant or have repeated miscarriages can test for this through a simple blood test. There are treatments available, but there is no guarantee that you'll subsequently get pregnant and carry a baby to full term.
The process of ovulation is when a mature egg is released from the ovary, then moves down to the fallopian tube, where it's ready to be fertilised. When you're trying to get pregnant, you need to have sex during the 'fertile window' of your menstrual cycle, which is generally five days before ovulation and on the day itself. Problems with fertility arise when a woman doesn't ovulate regularly.
Polycystic Ovarian Syndrome (PCOS)
PCOS is a common fertility problem that has no known cause, although doctors believe that genetics could play a role. It affects a woman's fertility because it causes a hormone imbalance. The ovaries of women with PCOS make a higher level of androgens than normal; androgens are male hormones that are also present in females. High levels of androgens affect the process of ovulation and, thus, a woman's fertility.
Quantity & Quality
Both the quantity and quality of a woman's eggs play a big part in her fertility. Women are born with a certain number of eggs and this number starts to decline in our early 30s. There are tests that determine a woman's ovarian reserve. They will show whether or not she has an average, better than average or lower than average number of eggs for her age.
Quality, however, is harder to determine, and age is the best detector of this, as the chances of chromosomal abnormalities in eggs increase significantly with age.
Recurrent Pregnancy Loss
For some women, getting pregnant isn't the problem - but keeping the pregnancy is. Recurrent pregnancy loss is a condition when a woman has two or more miscarriages before the pregnancies reach 20 weeks. It also has to be a clinically recognised pregnancy, which means it has to have been seen on an ultrasound or that pregnancy tissue was identified after the miscarriage.
This is the test that men go through to determine if there are any problems with their sperm when a couple is having problems conceiving. It looks at three main things - the number (count) of sperm, the shape (morphology) of the sperm, and the movement (motility) of the sperm.
The thought of whether or not you may have fertility problems usually only crops up after a specific period of time. For women under 35, this is after one year of trying to conceive, which refers to having regular, unprotected sex. If you're above 35, you should see a doctor after six months of trying to conceive.
Sometimes, there really is no explanation as to why a couple is unable to conceive.
"Unexplained infertility means that the majority of possible problems are not present. Yet the couple cannot succeed in having a live baby," says Dr Tan.
Sexually transmitted infections such as chlamydia and gonorrhoea can result in infertility if left untreated. Conditions that can develop as a result include fallopian tube infections and pelvic inflammatory disease (PID), which could cause permanent damage to the fallopian tubes and uterus.
Dr Chong lists some issues with a woman's womb that could affect her fertility:
If the fallopian tubes are blocked (due to infection or damage through trauma, and so on)
If there are growths in the womb, such as large fibroids, polyps and, in some cases, cancer
Abnormal anatomy of the womb such as undeveloped womb, double womb, septum (wall) in the middle of the womb or heart-shaped womb (bi-cornuate womb)
Damaged lining of the womb through bad scarring from such actions as multiple scraping of the lining as in multiple previous abortions.
A hysterosalpingogram (HSG) is an X-ray of your uterus and fallopian tubes, and is one of the tests done to diagnose possible fertility problems. A dye is injected through the cervix and it travels to the uterus and fallopian tubes. The doctor or radiologist is then able to see if there are any blockages that are affecting your chances of getting pregnant.
Age plays a big part in a woman's fertility. "The quality of a woman's eggs starts to worsen from the age of 25," Dr Chong explains. "This drop is slight and gradual. It is steeper from age 35 and very steep from age 40."
"In addition, the older the woman is, the more likely she is to have medical problems such as high blood pressure and diabetes, which lead to fertility issues. The risks of foetal abnormalities increases with age and the embryo may not be formed at all because of this abnormal egg."
Dr Chong also adds that the risk for a woman having a baby with Down Syndrome is 1 in 330 at age 35, 1 in 100 at age 40 and 1 in 50 at age 45. What's more, the chance of IVF success for women under 35 is about 40 per cent. At 40, it's about 10 per cent and at 45, it's 5 per cent.
Zygote Intra-Fallopian Transfer (ZIFT)
This is a procedure in which a fertilised embryo is transferred directly into the fallopian tube instead of the uterus, which is what is done during IVF.
Dr Chong explains: "ZIFT is an assisted reproductive procedure during which eggs and sperm are combined outside the body to form a zygote, which then progresses to become an embryo that is implanted in the womb for IVF.
"In a normal pregnancy, the egg meets the sperm in the fallopian tube. ZIFT tries to mimic this. When an embryo is implanted and an IVF cycle fails, it may be hard to determine whether it was due to the embryo or the womb.
"In some centres, ZIFT is considered after failed IVF. This can be done in Singapore but is not common as it's a more complicated procedure. Success rates are similar to IVF."
Simply Her is now available in both print and digital formats. Log on to www.simplyher.com.sg to subscribe!