You are here:

Infertility/Fertility/follicle size vs LH surge


I had femara 5mg day 3-7 on CD7 I had an Ultrasound, which showed healthy looking ovaries and 3 follicles sizes 15mm, 14mm, and the last one was 17mm!! My Doc said to start having intercourse every other day starting that day. He also mention to start testing for LH surge starting the next day CD8 because he though I would probable ovualte in the following couple of days, but I didn't get my 1st day of LH surge until CD13. I'm confused did I not ovulated until after CD13 or did indeed ovulated before that based on my follicles size?

Hello Jennifer from the U.S. (Minnesota),

The LH surge is a natural hormonal rise that occurs prior to ovulation.  Without the surge ovulation does not occur unless you take HCG injection.  So if you were following an OPK to detect the LH surge and it did not occur until CD#13, that means that ovulation would not have occurred until after than date.  That would indicate that the 17 mm see on CD#7 was probably an incorrect measurement.

Good Luck,

Dr. Edward J. Ramirez, M.D., FACOG
Executive Medical Director
The Fertility and Gynecology Center
Monterey Bay IVF Program

Monterey, California, U.S.A.

for additional information check out my blog at check me out on twitter with me at @montereybayivf and facebook @montereybayivf.  Skype and internet comprehensive consultations now available via my website for those who want a more extensive evaluation that this site can accommodate


All Answers

Answers by Expert:

Ask Experts


Edward Joseph Ramirez, MD, FACOG


I am a specialist in infertility and advanced gynecological care. I can answer questions about infertility, gynecology related ills, menopause...virtually anything that affects women's health. PLEASE tell me where you are writing from as I am always interested.


I have been practicing as an Ob/Gyn and Infertility Specialist for over 23 years. Gynecology, advanced laparoscopic surgery, basic infertility, IUI's, IVF, reproductive surgery, and ovulation induction are all areas of my expertise. I am Board Certified. I have been doing In Vitro Fertilization in my clinic for 19 years.

American College of OB/GYN, American Board of Obstetrics and Gynecology, American Society of Reproductive Medicine, California Medical Association, American Association of Gynecologic Laparoscopists, Fellow of The American College of Obstetricians & Gynecologists

American Journal of Obstetrics and Gynecology, Wall Street Journal, Monterey Herald, SERMO, Women's Health and Fertility Blog

Medical Degree from Stanford University, Residency at Tripler Army Medical Center, Reproductive Training at Pacific Fertility Center, San Francisco

©2017 All rights reserved.