Recognising the early signs can help you find out about a pregnancy sooner, which will benefit you in the long run.
When women aren't expecting to become pregnant they often don't realise, or put off confirming, they are until well into the first trimester or even later. This means they risk missing out on important antenatal care and if they decide not to continue with the pregnancy, it can limit their termination options.
Testing for pregnancy
During early pregnancy, a woman's human chorionic gonadotrophin (hCG) levels rise rapidly. A pregnancy can be confirmed if this hormone is detected in either her blood or her urine.
Blood tests involve a doctor or nurse taking a blood sample and sending it to a laboratory for screening. It can take several days for results to come back.
Home pregnancy tests look for hCG in a woman's urine. These take only minutes to show results and can be purchased at most pharmacies and supermarkets. Some can detect traces of hCG as early as 11 days after ovulation (about five days before a missed period), however often hCG levels are not high enough to show up by this stage. For accurate results, blood or urine tests should be performed after the first day of a missed period.
Why it is important to test early
Technically, a pregnancy begins on the first day of a woman's last period, not at the moment when an egg is fertilised. This means that by the time most women miss a period and perform a positive pregnancy test, they are already more than four weeks pregnant.
Finding out about pregnancy early has many benefits. It means woman can start receiving important antenatal care to protect themselves and the developing baby, and if they choose not to continue with the pregnancy, it means they have more options for termination.
Why women might not know they are pregnant
One of the telltale signs of pregnancy is a missed period. However, many women are not alarmed, or may not even notice, if they miss one. A woman's menstrual cycle is affected by diet, weight loss or gain, changes to exercise schedules, stress, illness, hormonal imbalances, uterine abnormalities, breastfeeding and some medications. If a woman normally experiences irregular periods for any of these reasons, she may overlook a missed period caused by pregnancy.
Some women experience spotting or light bleeding in the early stages of pregnancy. This is called 'implantation bleeding'. It generally occurs between six and 12 days after ovulation, when the fertilised egg attaches itself to the lining of the uterus. If a woman mistakes this for a period, she may not suspect she is pregnant until she misses her next expected period.
Similarly, it may take weeks, or even months, for a woman to realise she is pregnant if she conceives while tricycling the pill (running several packets together and omitting the hormone-free pills to avoid menstruating). Women on the pill risk ovulating if they miss some of their active doses, or don't properly absorb them (due to vomiting, diarrhoea, or the use of some antibiotics (see our Antiobiotics and the Pill article ). If this leads to pregnancy, a woman may not suspect she is pregnant until she next takes the hormone-free pills and doesn't experience a regular 'withdrawal bleed' (the normal, period-like bleeding that occurs between cycles of active doses).
Early signs of pregnancy
The dramatic hormonal changes that occur in a pregnant woman's body can trigger a variety of symptoms. About seven days after the fertilised egg is implanted in the uterus, a hormone known as hCG is produced. This hormone stimulates a surge in oestrogen and progesterone production. As a result, many women experience some or all of the following symptoms:
A woman's blood production, heart rate and breathing increase during early pregnancy, while her blood sugar levels and blood pressure drop. At the same time, high progesterone levels slow the metabolism. Combined, these changes can trigger feelings of overwhelming fatigue as early as one week after fertilisation.
Most women's breasts undergo rapid changes during early pregnancy. From about week three, the breasts can become swollen and tender and the veins in the breasts may appear more obvious. By the end of the first trimester, the areolas (skin around the nipples) usually become larger and darker in colour. Some women also notice the appearance of Montgomery's tubercules (small, white, goose-bump-like spots) on their areolas.
Despite its name, morning sickness can occur at any time of the day or night. The symptoms, which include nausea, vomiting and loss of appetite, generally begin about two weeks after fertilisation and subside about 12 weeks into pregnancy, although in some cases they can continue into the second trimester or throughout the entire pregnancy.
Pregnancy causes an increase in body fluid and in blood flow to the kidneys. In turn, the kidneys produce larger amounts of urine. It is common for pregnant women to experience an increased need to urinate after about four-to-six weeks of pregnancy.
Food cravings and aversions
It is not unusual for pregnant women to crave particular foods or to experience a sudden distaste for foods they previously enjoyed. Some women also develop an urge to eat non-food items such as soil, chalk or paper. This phenomenon is known as 'pica'.
Sensitivity to smell
Pregnancy can alter a woman's sense of smell. During the first trimester, some women find scents and odours they'd previously not noticed to be much stronger. Often they have trouble tolerating particular smells or experience nausea upon encountering them.
Soon after implantation, a woman's uterus begins to enlarge to accommodate the pregnancy. As this happens, many women experience cramps that feel similar to menstrual cramps. Other women feel as though their uterus is 'full' or 'heavy', likening this to the sensation they experience prior to menstruation.
Other pregnancy symptoms
The hormonal changes that occur during early pregnancy can affect a woman's mood. Feelings of irritability or tearfulness are common. From about six weeks, increased blood flow and high progesterone levels can cause nose bleeds, swollen or bleeding gums, and acne break-outs. Some women also experience headaches, dizziness, leg cramps and nasal congestion.
Continuing a pregnancy
As soon as a woman confirms she is pregnant, she should make an appointment to see a doctor or midwife to start receiving antenatal care. There are several antenatal tests available and some need to be performed at specific times during a pregnancy. Finding out about pregnancy sooner gives women the opportunity to book and prepare for these appointments and tests in advance. This is particularly important for women who need to travel to get to their doctor or midwife.
When a woman finds out that she is pregnant, her doctor or midwife will undertake a full blood analysis and examine her medical history. Any chronic health conditions she has (e.g., diabetes) need to be monitored during pregnancy and any prescription medications she is taking (e.g., antidepressants) need to be discussed. Doses may have to be altered because pregnancy causes metabolic changes, and medications that could harm the developing embryo may have to be stopped.
Diet and nutrition are important during pregnancy. Doctors and midwives may recommend antenatal vitamins and folic acid supplements, which assist with the healthy development of the baby and help prevent neural tube defects. They often recommend that certain foods be avoided (e.g. soft cheeses and raw fish could be contaminated with harmful bacteria that can lead to an infection that can increase the risk of miscarriage, stillbirth and premature labour) - see our Listeria and Pregnancy article. Women should avoid drinking and smoking, discontinue using hormonal birth control methods and limit their exposure to harmful chemicals and x-rays. For more information, see our Preconception and Pregnancy Health fact sheet.
Between week nine and the end of week 13, a first-trimester screening test is offered to identify whether the pregnancy has an increased risk of producing a baby with chromosome abnormalities (such as Down syndrome). For most women, week nine occurs just after the date of the second missed period, so finding out about the pregnancy early will make it easier to book and prepare for this test. It is an optional screening test that combines the results of a blood test (performed between weeks nine and 12) with the results of an ultrasound (performed during weeks 12 or 13) that allows the thickness of the fluid at the nape of the baby's neck (the nuchal translucency) to be measured. If this test is missed, there is the possibility for a second trimester screening test, but many women prefer to find out about potential problems early in their pregnancy so they can plan for their baby's needs or think about termination.
The location, availability and cost of terminating a pregnancy change as the time progresses. In Australia, most abortions are performed in the first 14 weeks of pregnancy. Abortion is a procedure that involves the removal of the foetus or embryo from the uterus, often involving surgery. Non-surgical, or medical, abortion is a cheaper, less-invasive alternative to surgical abortion, however it can only be performed on women who are less than nine weeks pregnant and in good health.
A medical abortion involves the woman taking mifepristone (also known as 'RU486' or the 'abortion pill') to block the action of progesterone. Since high levels of progesterone are needed to sustain a pregnancy, this results in miscarriage. The procedure doesn't require anaesthesia or a surgeon. Although mifepristone (or RU486) is now listed on the Pharmaceutical Benefits Scheme (PBS), it is still limited in availability. For further information on termination options, please visit Children by Choice.
Last updated: 9 March 2016
© Women's Health Queensland Wide Inc. This article was written by Joanna Egan and reviewed by the Women's Health Queensland Wide editorial committee. It was published in Health Journey Issue 2 2012.