What are “baseline labs”? Ask Dr. Doyle

QUESTION: I recently read an article that mentioned “baseline labs”. I realize it has something to do with infertility and testing, but I couldn’t fully understand the article. Can you explain what a “baseline lab” is?

Dr. Doyle: Many hormonal steps must fall into place for a woman to ovulate, and natural fluctuations of these hormones are needed to enable eggs to develop and ovulate. But if these natural cycles are disrupted by hormones that are either too high or too low, then infertility can result. The best time to check these levels is at the beginning of the menstrual cycle (day 2 or 3) because they are at their natural baseline. When hormonal imbalances are found they are usually easily corrected.