When a Choice Mom-in-the-making posted several questions on the discussion board about FSH, I asked Los Angeles-based Dr. Arthur Wisot for his input. The woman wondered, since FSH numbers can vary from month to month, how successful they actually are at predicting an ability to conceive — and to deliver a healthy baby — and whether there are things under our control to improve that number.
About reliability as a measurement, Dr. Wisot reported: The FSH is a powerful predictor of successful healthy live birth. As with any test, there are individuals who fall out of the norm. It’s a matter of probability. For example, a high FSH might predict a 5% chance of a live birth. It is just that. It means five out of a hundred women will achieve a healthy pregnancy as opposed to a much higher percentage of women who have a normal FSH at a particular age. In an individual it will be 100% or 0%, but the group relationship applies to her probability.
Q: When FSH numbers change, does it reflect changes in your fertility, or measurement error?
Dr. Wisot: It probably reflects dynamics in the balance between the pituitary and ovaries going on in one’s body. The prognosis, however, is thought to be based on the highest FSH. So a cycle with a lower FSH probably does not indicate a better chance as the FSH is a response to the last cycle, but it may indicate a better chance of getting a better stimulation.
Q: Are there other measures of fertility (e.g., antral follicle count, inhibin B) that do a better job of predicting individual pregnancy rate? Can these measures be combined to produce an accurate prediction for an individual’s chance of pregnancy?
Dr. Wisot: Any prediction is general. We do not know which individuals will be in the small percentage who succeed. The inhibin B and FSH tell you roughly the same information: the quality of the eggs. The antral follicle count and Anti-Mullerian Hormone (AMH) are more measures of the number of follicles in the ovaries capable of producing eggs when stimulated with fertility drugs.
There is a book on this issue, Inconceivable by Julia Indichova. When I wrote Conceptions & Misconceptions we were interviewed on the same program together on our book tours. She had a very high FSH and was successful and attributed it to a regimen which she outlines in the book. There is no scientific evidence that her regimen works and she may just be the one who succeeded. But she is very sincere and the book is inspirational to those struggling with this issue.