Ask Dr. Michael D. Fox about nutrition, low carb and fertility


Are you having problems with your menstrual cycle? Perhaps you’ve been diagnosed with PCOS or perhaps you suspect you have it? Are you interested in how low carb diets can help and how to maximize the benefits? If so, then go ahead and ask your questions to our expert on the subject, Dr. Fox.

Ask Dr. Fox about nutrition, low carb and fertility – for members (free trial is available.)

Below are some questions answered by Dr. Fox:

Questions and answers

Hi Dr Fox,
I’m a 31 y/o with BMI 25.
I have experimented with lchf over the last couple of months and have found it to be very beneficial. In the last couple of weeks I have been back on starchy carbs & sugar but have just found out I am about 6 weeks pregnant with my second child (had a heavy week long period so did not at all suspect pregnancy). I’m now highly motivated to get back to eating a lchf diet, is it safe to commence the change in diet whilst pregnant?
Many thanks in advance,

As you found the dramatic benefits of the diet in the non-pregnant state, converting back now will benefit the pregnancy far beyond any possible adverse effects of such a conversion. As long as you prevent hypoglycemia, there should be absolutely no adverse consequences. Sadly, all women on the usual carb diet, experience repetitive hypoglycemia, a process that likely has a very severe negative effect on the pregnancy! So just take in calories every 2-3 hours over the first 6 weeks or so and you will be fine. Best of luck and remember, there is nothing that even remotely approaches the benefit of LCHF for your child in regards to it’s long term health and success.
Thanks for a great question.

Dr. Fox

Dear Dr Fox,
Thank you very much for the interviews you made, it has been very helpful,
I will have an embryo transfer in January and I began the keto diet 7 weeks ago in order to lose weight and to increase success of pregnancy (my BMI was 33 before the diet). So far I lost 15 pounds and I feel great. I was thinking to stop the keto diet 3 weeks before the embryo transfer but after seeing your videos and some feedbacks from “keto mom” I think I must continue the diet.
Have you some insights regarding embryo transfer and keto diet? Our difficulties to conceive are from my husband that has a low sperm account.
Thank you very much for your help

Don’t Stop!! You are absolutely correct in reading Keto Mom. It is hard to get the idea across to patients that even if you are “normal” in terms of metabolic function, carbohydrates and insulin elevation still create an abnormal hormonal environment, drain on your health and definitely less than optimal reproduction. My guess is that the cave man probably achieved pregnancy nearly every month of trying. look at the early 20th century where women had 12 and 15 children. You can’t do that if it takes a year or two to achieve pregnancy. The only differences really lie in nutrition.

So for example, if insulin increases testosterone production in the ovary (and uterus) and your embryo is trying to implant in the endometrial lining, the testosterone will tend to create and unfavorable endometrial environment and make implantation harder. Not impossible just harder. This might result in extra IVF cycles needed. Further, I would suggest that your best pregnancy outcome will result from a ketogenic diet. More focus has recently centered on the “signals” from mother to child that may turn on the insulin resistance / metabolic syndrome genetics. So to summarize, I would recommend the LCHF for life for everyone and all systems including reproduction and pregnancy will improve. It is not just for the metabolically impaired or PCOS patient. Best of luck to you in your journey.

Dr. Fox

Dear Dr.Fox,
I’m a 24 year old female, 5’7″, 220 lbs, and I’ve been on a Strict LCHF diet for roughly 6 months now and have I lost roughly 35 lbs. So around the age of 11 I was highly active playing basketball and softball, mostly fit, energetic, all around healthy. Well towards the end of my 6th grade year I started my period and with it came a lot of problems. My periods were irregular and heavy and I started to feel tired all the time and If I remember correctly my 7th or 8th grade year I had an iron deficiency which I can only assume was caused my heavy periods. Once I started to take the iron pills I felt somewhat better but as soon I was off of them I didn’t feel sick any more but I still felt really tired.

Some time went by and when I entered 8th grade I felt I gained weight, though I’m not sure how much i weighed by i remembered having thicker thighs, my upper arm area seemed thicker and I had kind of a pot belly. In 10th grade I stopped playing sports and gained even more weight still having heavy periods, irregular periods, and fatigued almost all the time. This continued until I entered college where I lost a good amount of weight going from 230 lbs down to ~180 lbs during my freshman year but then I noticed that I had irregular bleeding in between my already irregular periods. For a while I didn’t think much of it but it became more noticeable my junior year of college and that’s when I found out that I had a Dermoid cyst on my right ovary (it was 8 cm big).

So now leading up to my senior year and post college years I’ve found that I feel none of my symptoms have resolved (irregular periods, heavy bleeding, etc) and now I’m starting to have trouble staying focused and remembering things; I’ll even have moments where I think of something and almost immediately forget what i was thinking or doing. I’ve been told by a gynecologist that I have a hormonal imbalance but I think her way to initially handle it was birth control, I don’t believe she told me anything other than, “you have a hormone imbalance, take birth control”.

Ok now to the questions, so I said in the beginning that I’ve been on LCHF for 6 months now and I’ve measured my ketones using dipsticks which result from trace amounts of ketones to large. Also the dipsticks i have also measure glucose and that part has resulted in no glucose. So If I do have a hormone imbalance at my age what would you prescribe to return hormones to normal and what other information should i look for or ask?


Kathleen, your story is all too familiar. What you describe sounds like PCOS with the typical pubertal onset of metabolic dysfunction. As your insulin resistance and dysfunction has worsened over time, your symptoms have increased. Obviously, there is no way to make a definitive diagnosis over the internet and you will need to find someone who really specializes and understands PCOS. Hopefully that person would also understand LCHF nutrition as well but we are hard to find. Even without the nutrition coming from the doctor, you can do that part on your own. The nutrition is probably 80+% of the treatment, but medications to help you cycle correctly such as birth control, and drugs to help with skin changes are important. We advocate using metformin as well to aid the function of insulin and hopefully reduce your insulin levels. Of course there are other reasons for worsening cycles and people with PCOS are at increased risk of polyps and endometrial abnormalities so you should definitely get that evaluated. If your doctor will, I would suggest a 3 hour glucose tolerance test with insulin levels at each time point to look at your insulin curve.

The memory issues are a little more confusing to explain. We now see that maybe more than 50% of women on birth control actually suffer from low estrogen. Even though there is estrogen in the pills, (or ring) patients are not absorbing enough and have many symptoms of low estrogen: low libido, memory and concentration problems, mood changes, migraine headaches, anxiety, depression, night sweats, vaginal dryness, bladder frequency and urgency etc. etc. Does this sound familiar? If you can get some supplemental estrogen from your doctor this will resolve. It’s just hard to convince most doctors because we were all taught that you were getting 3-5X the amount of estrogen you need in the pill. Unfortunately now with low dose pills that just isn’t so and so many women don’t absorb oral estrogen well. Again these are all just thoughts and you need a thorough evaluation.

As to the energy drain, all our patients with insulin resistance and metabolic syndrome are severely fatigued. That is part of the energy metabolism problem and should resolve over time. If you are fatigued on LCHF, you could be restricting calories or suffer from sleep apnea.

Hope this helps.
Dr. Fox

More Questions and Answers

Read all earlier questions and answers – and ask your own! – here:

Ask Dr. Fox about nutrition, low carb and fertility – for members (free trial is available.)

More with Dr. Fox

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Stressing Less to Get Pregnant – Dr. Michael Fox
Is Coffee Bad for You? – Dr. Michael Fox
The Cure for Morning Sickness
Women, Hormones and Nutrition – Presentation by Dr. Michael Fox
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