Positive and negative ovulation tests

How to effectively use Ovulation tests

Elize Kruger

Most people fall pregnant without giving it a second thought. But what do you do when it’s just not happening for you quick enough? That’s where Ovulation Predictor Kits (OPK’s) come in.

OPK’s are a very popular method for predicting ovulation. It can help you determine your most fertile window. It’s a quick, easy and accurate way to predict ovulation in advance.

How does OPK’s work?
Lets look at how ovulation happens: Firstly the Follicle Stimulating Hormone (FSH) starts the follicles growing, as the follicles grow oestrogen is produced to thicken your endometrium which is where the possible embryo may implant, then when everything is right another hormone, Luteinizing hormone, surges to trigger the release of the egg which happens within around 36 hours.

Luteinizing hormone is what the OPK picks up. As soon as your OPK shows a strong positive (bear in mind that a weak 2nd line is considered a negative), you will ovulate within 36 hours. This is your most fertile time. Sperm can survive for up to 5 days with an average of 48 hours, so intercourse before this time can yield conception as well.

Sometimes it happens that you use your OPK’s as prescribed and you still get a negative, then you can look at making a few changes, for example:

• Never use first-morning urine (FMU). Although this will give you a definite positive, it is possible that the LH concentrates in your urine overnight.
• Always use your second-morning urine.
• Test 4 hours after you last emptied your bladder. So avoid using the bathroom for 4 hours before your test. But if you are bursting then test as soon as you empty your bladder.
• Limit your water intake: We don’t want you to become dehydrated, but if you’re consuming large amounts of liquid in the hours before testing, your urine may become diluted, and you will have a negative and miss your LH surge.
• Test more than once a day. Generally, your LH spike lasts briefly, and you might miss the surge altogether and maybe miss out on conception that month.

The test line as has to be the same shade or darker than the control line: The reason for this is because as women we always have a small amount of LH in our systems, and we will ovulate only when the LH surge happens, and this is what the OPK’s pick up.

You may want to chart your basal temperatures while using your OPK’s. By looking at previous charts, you can quickly determine when to start using your ovulation tests.

It is best to test at the same time each day.

If you do not see a surge within the five days recommended by the manufacturers, test until you see a surge or until your temperatures have risen and stayed elevated for three days on your BBT Chart.