When you’re going through fertility treatments, getting to the stage when it’s time to take a pregnancy test can be really exciting but it can also create a lot of anxiety. It’s a critical step in a long process, so it’s important to understand what the test indicates. We explain everything you need to know about your pregnancy test.
When To Have a Pregnancy Test
Your physician will order a serum (blood) pregnancy test 14-16 days after treatment. Patients find this two-week wait to be very challenging but it’s important not to test any earlier since the injection used to trigger ovulation is synthetic bHCG (pregnancy hormone) which could result in a false positive.
The blood test your doctor orders measures human chorionic gonadotropin hormone (hCG). HCG is secreted by the developing placenta shortly after a fertilized egg has implanted in the uterine lining. The appearance of hCG soon after conception—and its subsequent rise in concentration during early gestational growth—make it an excellent marker for early detection of pregnancy. A blood serum measurement of hCG is more accurate than a urine pregnancy test because it measures the quantitative level of hCG.
Depending on the facility, bHCG measuring between 2 to 5mIU/ml is considered positive. If the test is positive, the physician will order a repeat test 48 hours later to ensure the levels are rising appropriately. Generally, a 66% rise in the bHCG is sufficient. Levels peak a week or two before the end of the first trimester of pregnancy (12 weeks) and decline in the second trimester. In addition to measuring bHCG levels, the physician will order a transvaginal or abdominal ultrasound to measure growth milestones such as fetal heartbeat. One can expect to hear the heartbeat around six weeks of pregnancy.
Melissa Bell is a nurse manager at Reproductive Medicine Associates of New York. After graduating from Our Lady of the Lake College nursing school in Baton Rouge, Louisiana, she moved to New York and fell in love with the field of reproductive medicine. Melissa is passionate about helping individuals and families meet their family planning goals. She is currently working on research for the American Society of Reproductive Medicine and strives to be an influential leader for her nurses and an advocate for her patients.