By Jane Palmer
These days, you don’t need to wait to see your midwife or doctor to find out whether you’re pregnant. Instead, you can opt for self-testing. Home tests are urine tests that usually simply give a positive or negative result. Your midwife or doctor, on the other hand, may perform either a urine test similar to the one you can take at home or a blood test to find out whether you’re pregnant.
Suppose you notice some breast tenderness or nausea, or you miss your period by a day or two. You want to know whether you’re pregnant, but you’re not ready to go to a midwife or doctor yet. The easiest and fastest way to know is to go to your local supermarket or pharmacy and pick up a home pregnancy test (or order one online). These tests are basically simplified chemistry sets, designed to check your urine for the presence of human chorionic gonadotropin (hCG, the hormone produced by the developing placenta). While these kits are not as precise as laboratory tests that look for hCG in blood, they can provide positive results very quickly from a day or two after your period is due.
Not all home pregnancy tests are the same. Some are more sensitive than others and can detect very low levels of hCG in your urine — around 15 to 25 mIU (milli-International Units) per millilitre of urine. Sensitive tests can provide a positive result within a day of a missed period, with 90 per cent accuracy. Other home pregnancy tests detect levels of around 40 mIU of hCG, meaning you need to be a bit further along in your pregnancy so that the hCG reaches detectable levels. The accuracy claims of home pregnancy tests typically range from 97 to 99 per cent and most are generally effective a week after your period is due. So, ideally, wait at least a week after your period is due before taking a test.
The results of home pregnancy tests aren’t a sure thing. If your test comes out negative but you still think you’re pregnant, retest in another week or make an appointment with your midwife or doctor.
Even if you have a positive home pregnancy test, some midwives or doctors may want to confirm the pregnancy test before beginning the rest of your prenatal care. Your midwife or doctor may decide to simply repeat a urine pregnancy test, or may use a blood pregnancy test instead.
A blood pregnancy test checks for hCG in your blood. This type of test can provide either a simple positive or negative result or an actual measurement of the amount of hCG in your blood. At 11 days after conception, hCG can be detected by a blood test. Levels of hCG double every 24 to 72 hours, reaching a peak at around 8 to 11 weeks into your pregnancy. Knowing the level of hCG in your blood from separate blood tests done over several days can be helpful if concerns exist about your pregnancy. The test your midwife or doctor chooses depends partly on your history and your current symptoms, and partly on your caregiver’s individual preference. Blood tests can be positive even when urine tests are negative.
© John Wiley and Sons
This article is an excerpt from Pregnancy For Dummies 3rd Edition (Australian and New Zealand Edition)
Your complete guide to having a healthy, happy pregnancy. This updated and expanded third edition of Pregnancy For Dummies offers mothers-to-be practical advice and expert guidance on every stage of their pregnancy — and beyond!
Understand what’s happening with your baby and your body, and be guided through what to expect from labour, birth and becoming a new parent.
Jane Palmer is a mother, birth activist and midwife in private practice located in Sydney, Australia. With additional qualifications as a childbirth educator and lactation consultant, Jane works to improve pregnancy, birth and parenting options for families.