Fertility Blood Analysis

Posted by Kassidy Finch



You may wonder why your hormone blood work analysis is taken on different days of your menstrual cycle. Hormone testing is an important tool used in assessing and diagnosing reproductive disorders.

In particular, testing for hormone levels on specific days of the menstrual cycle can provide valuable information about the functioning of the ovaries and reproductive system.

By measuring hormone levels on specific days of the menstrual cycle, healthcare providers can diagnose and treat a variety of reproductive disorders, such as polycystic ovary syndrome, endometriosis, and infertility.

If you are struggling with fertility or other reproductive issues, it is important to talk to your healthcare provider about whether hormone testing may provide insight to your difficulties.

Day 2/3 Vs. Day 21 Blood Tests

Follicular Phase Bloodwork

Day 2 or 3 testing, also known as follicular phase testing, is typically done on the second or third day of the menstrual cycle. During this phase, the levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), and estradiol are measured. These hormones play important roles in stimulating the growth and development of follicles, which house the eggs in the ovaries. Elevated levels of FSH and LH, and low levels of estradiol, can indicate ovarian dysfunction or premature ovarian failure.

Luteal Phase Bloodwork

Day 21 testing, also known as luteal phase testing, is typically done 7 days after ovulation has occurred. During this phase, the levels of progesterone are measured. Progesterone is a hormone that is released by the corpus luteum, a structure that forms after ovulation. Elevated levels of progesterone indicate that ovulation has occurred and that the corpus luteum is functioning properly. Low levels of progesterone can indicate a luteal phase defect or anovulation.

Contact us to find out more ways we can support you on your fertility journey.

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