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LH Level

Posted: Tue Apr 02, 2019 10:42 pm
by kristinc
Hi Doctor,

I am a 35 year old woman with a history of PCOS. My Day 3 LH:FSH ratio has always been high and I suffered from very long (35+ day) or absent cycles. I conceived my daughter in 2015 through cycle monitoring with Letrozole and a shot of Ovidrel. We are currently trying to conceive baby #2. I did my Day 3 bloodwork which was 5.3 IU/L for my LH and 5.5 for my FSH. I was very happy about this result as I have never had a 1:1 ratio before. Today is now Day 6 and I went to get my LH checked as I am using the ovulation predictor kits and they are becoming increasingly difficult to read and my LH is now 11.5 IU/L! The lab range cut offs are 2-12 IU/L for the follicular phase and 8 -90 IU/L for the ovulatory phase. I looked online and some graphs that show that LH is only supposed to rise close to ovulation. With my LH being this high (and having risen so much in just 3 days) is this likely to pose a problem if we try to conceive naturally or with meds? I have not yet gotten a positive LH surge reading on the at home ovulation tests but am fearful that I will without actually ovulating since I am so early in my cycle. Please advise.

Re: LH Level

Posted: Fri Apr 05, 2019 10:31 am
by Dr. Rosen
The use of LH and FSH ratios to diagnose and treat PCO is very, very old fashion and is not part of current medical management of PCO but it sounds like it helped you before so let me do what we can to help you.

As you noted below, LH: FSH ratios used to be the hallmark of diagnosing PCO but no longer. Patients with PCO AT times but not consistently have higher levels of LH than normal ovulating women but at other times they do. A lot of women with classic PCO (having irregular cycles, elevated levels of serum androgens and having PCO-like ovaries on ultrasound) have normal levels of LH and normal LH:FSH ratios. Another comment is that all of the initial testing and diagnosis of PCO that used LH:FSH ratios was done looking at women in the early part of their menstrual cycle, i.e., days 3-5, and NOT later in the cycle. There is no data that I am aware of that looks at LH and FSH later on in the cycle.

With regard to your case, you said that you have “very long cycles”. If you are ovulating, remember that your urine ovulation predictor will turn positive only 1-2 days before ovulation. Please note that the time from ovulation to menstruation is usually about 14 days for your urine ovulation predictor should predict ovulation about 15-16 days before ovulation or on about day 16, if your cycle is 32 days long; on day 18, if your cycle is 34 days long; or on day 20, if your cycle is 36 days long, etc.

With regard to your conceiving, if you have PCO, you might not be ovulating and I would suggest that you have an ultrasound or two and a blood test for progesterone to confirm that you are ovulating.

Dr. Rosen

Gregory Rosen, MD
Reproductive Partners Medical Group, Inc.