How does it work, and after how long to do it?
The HCG Blood test is the most important tool for determining pregnancy. Sold in pairs, pregnancy home tests use urine and, only in specific cases, blood. They are highly reliable.
A fundamental moment in a couple’s life is finding out if they are pregnant by using a home exam. Dr Elisabetta Colonese is a Milan specialist in gynaecology and obstetrics and a consultant for the Mustela portal. She explains that the reliability of kits sold in pharmacies is around 95.99%, making them all very reliable. But how does it work, and above all, how long do you have to wait before taking the exam?
When should you do it to be effective?
“The basis of samples, both on urine and blood, is the detection of beta HCG, a hormone produced by the trophoblast, the first cells of pregnancy. Generally, this hormone begins to be present around 7-10 days after conception.” The expert clarifies, “In this case ‘conception’ means the union between the spermatozoon and the oocyte. Only then does the trophoblast begin to produce HCG.”
The first signs of conception are in urine. Furthermore, given the timing, it is necessary to wait until the first day of the canonical 28-day cycle to take the test: «It is always a good idea to wait until there are at least one or better two days of delay to do it. In a normal 28-day cycle, the sample is from the 29th day, but if it is always 35-40 days, wait between the 36th and 41st day before taking the exam.”
What changes between exam methods?
However, not all finger prick kits are the same. The one done on blood is faster. In this case, it is done between seven and ten days after conception. These kits use venous blood samples or finger prick samples.
The peculiarity of this exam is that, in addition to being qualitatively relevant, it also has the possibility of a quantitative value, making it a very reliable evaluation.
Depression issues
Not all women have to do it, “In fact, those who have to take a blood sample are mostly patients who have had problems in the past. These problems may include spontaneous abortions, biochemical, multiple miscarriages, or extrauterine pregnancies like salpingectomy (a surgical operation which consists of the removal of the salpinx or the uterine tubes). When the patient takes the urine sample, I ask for the quantitative value of beta HCG to understand better how it is going. The beta HCG value must have more than doubled after 48 hours.”
Instructions for use
Generally, they are sold in pairs. Once the first one is positive, another one will be used. Sometimes, the first one fails or is used incorrectly. For first-time patients, the hand can tremble, causing the urination strip not to be centred. I recommend inserting the sample directly into a sterile urine jar to be safe.
Is there a more suitable time of day? “Generally, you go crazy with the first urine because it is the most concentrated. Pregnancy blood tests are so reliable and done at any time of the day.”
When can the results be unreliable? “It happens when kits have expired, stored poorly, or done poorly, thus creating a false positive.”