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    Questions on LH surges and ovulation
    lisax4156 posted:

    So I have a question. My question is.. When you are using OPKs and they become positive, how soon after ovulation do they go negative again? Mine have been positive for 2 days noleftist sure if I've ovulated yet or not.

    Anyone know? Thanks:)
    Me (34) BF (32) DD (20) DS1 (16) DS2 (born 7-14-10 @ 36 wks, 5 lbs 14 ozs). TTC No.4... Thinking PINK for 2012!!
    David K Walmer, MD, PhD responded:
    Very interesting question & I don't actually have the answer but I can provide some insights. The LH surge can be identified in the blood stream or the urine. Because the pituitary releases LH directly into the blood stream, that is where is shows up first. The kidneys filter the blood and molecules that are small enough to pass through the filter also show up in the urine. Molecules that are too big stay in the blood stream. LH does pass through the filter. The urine LH surge always occurs after the surge in the blood stream and it lasts longer than the surge in the blood stream because of the transit time needed to make urine and then waiting until the bladder gets full enough to give you the urge to go. No one actually knows how long it takes for the eggs to be released from the ovaries after the LH surge in the blood stream. We know from our experience with IVF that you can find eggs in the ovaries 39 hours after the blood LH surge. Once we get eggs in the lab, they only appear to be receptive to sperm for the 1st 12-18 hours. After that, fertilization rarely results in a baby. A good rule of thumb is that sperm need to wait for eggs rather than trying to time intercourse. The cervix is a reservoir for sperm and holds and releases them slowly for days after intercourse. There is a 3-5 day window leading up to the positive OPK that there is enough water in the cervical mucous to let the sperm into the cervix "storage tank". A man should ejaculate once during the 5 day interval before the fertile window to move old sperm out of the way and then have intercourse at least once during the fertile 3-5 day window. The day that the OPK turns positive may be your last fertile day because of the delay that occurs before the LH shows up in the urine. If you haven't had intercourse within 3-5 days when the OPK turns positive for the first time, I would say that is a good day to procreate. After that you may be in recreation only window. I hope this helps. Good luck!
    Kangrrl replied to David K Walmer, MD, PhD's response:
    "The day that the OPK turns positive may be your last fertile day because of the delay that occurs before the LH shows up in the urine."

    Dear Dr. Walmer,

    I'm confused by your statement above, because in the instructions for my LH OPK strips (Wondfo), it says the best timing of intercourse is AFTER 24 hours, but no later than 48 hours, of your OPK . The timing seems to be critical, but there is so much conflicting advice out there.

    Can you determine an accurate answer?
    despmom replied to Kangrrl's response:
    I have been using clear blue opk since my first pregnancy. Clear blue shows a happy face referring to two peak days (first peak day morning and night, second peak day morning and night)..the third day it shows a blank face from morning itself, but if you have intercourse on the first peak day morning or night and second peak day morning until max afternoon, you have chances of getting pregnant, but later than 2nd day afternoon the chances aare almost nil though it shows a happy face on the second peak night. The reason it shows happy face on the 2nd peak night is though the egg is dropped, the surge will not go away that faster. This is my observation for years.
    Roxy0521 replied to David K Walmer, MD, PhD's response:
    Hi Dr. Walter,

    I am 25 years old and was on birth control pills for heavy periods since I was 15 years old. About 4 years ago I stopped having periods ( I did have one spontaneous period this January). A year ago my gynecologist attributed my lack of menses to the length of time on birth control pills and my low weight (100 pounds and am 5'2"). I started gaining weight and now weigh 110 lbs. and have been at this weight for about a year. She said i should start having periods again after about a year after stopping the pills. Still no period and it has been a year and a half. I am trying to get pregnant now and am having ovulation problems. I had a complete fertility workup and everything came back normal. I took progesterone pills to start my period and did, and have been through one cycle of chlomid and 2 cycles of femara. The gynecologist did an ultrasound during the last femara cycle and she could see the eggs getting ready to come out and said I was responding well to the femara. She told me to come in for a blood test and I did on Day 11 after my positive opk. The blood test was negative and she said she was "shocked". She had me come in for another test a week later and then another the next week and they were both negative. She then had the nurse call me and tell me they were referring me to a fertility clinic. I feel very discouraged and my question to you it possible that I did ovulate and was blood tested too late? And what might the next steps be at the fertility center? And are my chances to get pregnant better with all my tests being normal? I checked with good sources and it was a thorough work up. Thank you so much for your time.

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