One of the common questions that women have is “am I pregnant?” The obvious answer is to do a pregnancy test. It can, however, take up to 2 weeks for a pregnancy test to become positive after unprotected intercourse. This can be a long time for someone to wait to find out the answer.
Pregnancy tests look for the presence of a hormone called HCG. All pregnancy tests rely on the same technology and the big difference is how the test communicates the results. The less expensive tests have one line or two lines; the more expensive tests may say “pregnant” or “not pregnant.” There may also be differences in how the urine is placed in the device. The less expensive tests tend to be just as accurate as the more expensive tests.
If a women does not want to be pregnant and has unprotected intercourse the so called “morning after pill” can be used. This is packaged as “plan B” in the US. The Plan B works by stopping the ovary from ovulating and making it harder for the sperm to travel up the fallopian tubes. It does not cause abortion. The closer to the time of unprotected intercourse this is used, the better the chance that it will work. In the US, a prescription is not required. Plan B only has about an 80% success rate, there is a reason it is called Plan B and not Plan A. This is not a reliable form of birth control and is really for rare contraceptive failures. If Plan B is taken the women should seek medical care to be sure it was effective and to discuss more reliable birth control.
If a pregnancy test is negative, nausea, breast tenderness, bloating, or other typical early pregnancy symptoms are not a true indicator of pregnancy. These symptoms are all caused by the change in hormones that occur in early pregnancy. A negative pregnancy test tells us that the hormones have not yet changed enough to cause these symptoms.
My advice to patients that are exposed to pregnancy but are too early to have a positive pregnancy test, is to live life as if they are pregnant. Take a prenatal vitamin daily, refrain from alcohol, cigarettes, or drugs. Also continue to use birth control until pregnancy is confirmed.