Dr. Natalie Crawford: How Women Can Improve Their Fertility & Hormone Health

Why does it matter? Because a $79 blood test your doctor is forbidden to offer you could change every major decision you make in your reproductive life.

Dr. Natalie Crawford — double board-certified reproductive endocrinologist and fertility surgeon — dismantles the assumptions most women carry into their peak reproductive years. The system is structured around failure: you must prove you cannot conceive before anyone will test why. Crawford explains exactly what women can know, test, and change right now — before that failure window ever opens.

• A $79 AMH blood test measures your ovarian reserve and is actively withheld from healthy women by official ACOG guidelines — order it yourself if your doctor refuses • Egg freezing does not deplete your reserve; it rescues eggs already scheduled to die that month regardless • Male cannabis use cuts fertilization rates by 28% and raises miscarriage rates — it is both partners' problem, not just the woman's • Biotin over 300 micrograms falsifies readings for estradiol, progesterone, hCG, TSH, and testosterone — stop it 7 days before any hormone panel

The medical system requires women to fail before it will test them — and that failure window destroys options

Crawford's bitterest clinical frustration: by definition, infertility means trying to conceive for 12 months without success. Only after hitting that failure threshold will a physician check ovarian reserve, run a semen analysis, or investigate fallopian tube anatomy. Yet 72% of couples who will conceive do so in the first six months of trying. The remaining 13% conceive in months seven through twelve — which means the patients who genuinely need investigation are waiting an entire year to learn something that could have been caught on day one.

Crawford has sat across from couples who tried for years, were dismissed as young and healthy, and eventually discovered blocked tubes, uterine birth defects, or zero sperm. "We should test things," she says flatly, "and if it's all normal, maybe you do just go try your six or 12 months." The current model inverts that logic entirely.

For women over 35, the evaluation window shortens to six months of trying — but Crawford argues even that is too conservative given what a basic panel costs versus what a delayed diagnosis costs emotionally and financially. The data point that should reframe how everyone thinks about timing: fecundability (probability of pregnancy per month) drops from 20% at age 30 to 11–12% at 35–36, to 5% at 38, and to 3% at 40 and beyond. None of those numbers are zero — but each one represents a compressing window where withheld information becomes actively harmful.

The AMH test costs $79 — and your doctor is officially advised not to give it to you

Antimüllerian hormone is made by the granulosa cells surrounding each ovarian follicle. More eggs in the vault, more come out each cycle, more AMH circulates. It's an imperfect but meaningful proxy for ovarian reserve — not egg quality, Crawford is careful to note, but egg count. Two 30-year-olds with the same partner exposure have the same monthly conception odds whether one has 20 eggs outside the vault or five. But the woman with five will run out faster, respond less robustly to stimulation, and go into menopause earlier.

The American College of OB-GYN explicitly states women should not have AMH checked unless they already meet the infertility diagnosis. Crawford's reaction: "This is wild to me."

The deeper reason to test isn't just timeline planning. About 50% of the time Crawford finds a low AMH, she also finds a treatable cause: Hashimoto's thyroiditis, insulin resistance, endometriosis, or another autoimmune condition actively accelerating egg loss. Treating Hashimoto's slows the inflammatory damage to ovarian tissue. "I can't reverse the clock, but I can slow down the rate of inflammation."

The $79 test is available at any LabCorp through a self-pay request, through Function Health, or by simply asking your doctor and, if refused, ordering it yourself. Crawford's protocol is categorical: if you ever want children, get this test now. File the result under one of four categories — normal, above average, below average, critically low — and act accordingly.

Egg freezing doesn't touch your reserve — it rescues eggs already dying that month

The number-one reason women delay or skip egg freezing is the fear that stimulating multiple follicles will accelerate ovarian decline. Crawford calls this fear biologically unfounded and says it "really does need to be busted."

The mechanism: every month a cohort of eggs exits the vault whether you ovulate, are pregnant, breastfeeding, or on birth control. In a natural cycle, one egg is selected, ovulated, and everything else in that cohort dies. IVF stimulation uses FSH — the same hormone the brain produces — to push every egg in that month's cohort to maturity instead of letting them die. The vault itself is untouched. "Doing IVF or egg freezing is not going to decrease your ovarian reserve. It is simply going to influence one month in time trying to not have all those eggs die."

This reframes the cost-benefit entirely. Freezing at 28 means three times as many eggs per retrieval compared to freezing at 37. Earlier freezing is not a fertility risk — it is leverage on eggs that are already on the way out. The practical corollary Crawford draws for couples who've had a first child and are planning a second: prior pregnancy raises monthly fecundability to 18–20% all the way through age 37, at which point it drops sharply. Secondary infertility is real, sperm counts change with age, and endometriosis is a tincture-of-time disease. Six months of trying past 35 without a pregnancy warrants evaluation, not patience.

Male cannabis use programs embryo failure — embryologists can identify it retroactively at day three

Cannabis use has become the most actionable and most underappreciated fertility variable Crawford sees in clinical practice. The data, now robust because legalization has enabled research, are striking: cannabis use in the prior year cuts eggs retrieved at IVF by 25%, drops fertilization rates by 28%, and raises miscarriage rates enough to meaningfully reduce live birth rates. These are numbers that generate excitement in fertility research when an intervention shifts outcomes by a few percentage points.

The male side is where most couples are blindsided. THC damages sperm DNA fragmentation inside the sperm head. When an embryo arrests at the male developmental checkpoint — day three, before the paternal genome even activates — Crawford's lab goes back to the history. "Nine out of ten times he is using cannabis that he previously denied." Female partners who conceive from a male cannabis user face substantially higher miscarriage rates than those whose partners don't use.

THC crosses the placenta directly. Edibles typically deliver the highest THC loads. The placental dysfunction that follows impairs nutrient delivery, is associated with earlier birth, and shapes developmental outcomes in ways that extend beyond the conception event itself.

Sperm renews every 90 days. Both partners should eliminate cannabis at minimum 90 days before attempting conception. The argument that someone "got their partner pregnant while using cannabis" misses the point: the question isn't whether conception occurred, it's whether the resulting embryo, placenta, and child reached their biological potential.

Ibuprofen mid-cycle blocks ovulation entirely — even when every hormonal signal proceeds normally

Acute inflammation is not the enemy. It is required for conception. When a follicle ruptures to release an egg, that rupture is an inflammatory event — and NSAIDs suppress the prostaglandin cascade that makes it happen.

Crawford's clinical directive: ibuprofen, Advil, naproxen (Aleve) taken around the time of ovulation will prevent the follicle from rupturing. Hormones surge normally, the LH spike occurs, all the signaling looks right — but the egg does not release. "They will go through the hormonal changes of ovulation, but the egg will not be released."

The protocol is specific: NSAIDs are acceptable only during the menstrual period itself, when cramping is the target and ovulation is days away. For the rest of the cycle — any headache, any joint pain, any inflammation — switch to acetaminophen. Most women trying to conceive have no idea their over-the-counter pain reliever is eliminating their chances that month. Most physicians don't flag it.

Cold plunges earn a similar caution from Crawford. They're a potent suppressor of the acute inflammatory response that ovulation requires. She doesn't consider them as reliably disruptive as NSAIDs, but recommends against them during the conception window. The sauna, notably, gets no such restriction.

A regular 34-day cycle can be hiding stage-one ovulation disorder — you need to track ovulation, not just bleeding

Crawford lays out a precise sequence: ovulation disorders progress through a predictable pattern, and the first stage produces no cycle irregularity whatsoever. The initial signal is a shortened luteal phase — the interval between ovulation and the next period. Under 11 days is abnormal. But because the follicular phase compensates, cycles appear regular.

The implication for the standard "are your periods regular?" screening question: it misses stage one entirely. A woman with a 34-day cycle, ovulating on day 23, has a luteal phase of only 11 days. Her cycles look textbook. Her progesterone production is compromised. Her brain and ovary are miscommunicating. And none of that is visible unless someone is tracking when she actually ovulates.

Ovulation predictor kits and cycle wearables give this data. Time from the LH surge to period onset — that's the luteal phase. Under 11 days warrants testing for prolactin, thyroid function, AMH, and PCOS even in the presence of regular cycles. The second stage of ovulation disorder is a prolonged follicular phase; the third is true cycle irregularity; the fourth is amenorrhea. Stages one and two are the intervention window. "Tracking ovulation is going to allow us to know how long is your luteal phase... ovulation disorders progress through a very predictable pattern."

GLP-1 agonists at low dose are improving IVF embryo outcomes in inflammatory disease — independent of weight loss

The most frontier-facing clinical observation Crawford shares is about GLP-1 receptor agonists — semaglutide-class drugs — used at low dose for three months before an IVF stimulation cycle in patients with endometriosis or suspected chronic inflammatory disease.

Endometriosis can only be confirmed surgically, which means roughly 50% of unexplained infertility patients are walking around with undiagnosed endo driving their poor IVF outcomes. When Crawford puts these patients on a low-dose GLP-1 for three months, stops it, then cycles them through retrieval, she sees more embryos in the lab. Colleagues across the country are reporting the same pattern.

Critically, some of these patients carry little adipose tissue — meaning the benefit is not mediated by fat loss. Crawford and her colleagues believe GLP-1s are acting directly on the inflammatory cascade, possibly at the hypothalamic and ovarian level, suppressing the chronic immune activation that interferes with follicle development and embryo quality. "GLP-1s can be very anti-inflammatory," she says, "and the way to kind of target that... what appears to be that inflammatory burden."

The protocol she uses — low dose, three months, stop before stimulation — is explicitly distinct from weight-loss dosing. Women with unexplained IVF failures, repeated poor embryo outcomes, or known endometriosis should ask a reproductive endocrinologist comfortable working at this frontier about whether a short GLP-1 course makes sense before their next cycle.

Biotin over 300 micrograms makes your hormone labs meaningless — and hair supplements contain 10–30 times that amount

One of Crawford's most practically urgent warnings concerns something millions of women take daily without suspecting it can invalidate every hormone test their doctor orders.

Biotin at 300 micrograms or above, taken for seven or more consecutive days, binds to the steroid assay used by clinical labs. The result: false readings for estradiol, progesterone, hCG, TSH, and testosterone. Not slightly off — untrustworthy. During an IVF monitoring cycle, where estradiol levels guide medication adjustments in real time, this produces dangerous clinical decisions.

The exposure level that triggers the problem is trivially easy to hit. Popular hair, skin, and nail supplements routinely contain 2,500 to 10,000 micrograms of biotin — 10 to 30 times the threshold. Many labels list it as "vitamin B7" without flagging the amount. Patients going through IVF often start these supplements for hair loss related to stress or hormonal changes — precisely when accurate lab monitoring matters most.

The fix is straightforward: stop all biotin-containing supplements at least 7 days before any hormone blood draw. Check every supplement label, not just dedicated biotin products. If testing is urgent and biotin cannot be stopped, tell the lab — some assay formats are less susceptible than others, and the result should at minimum be flagged as potentially unreliable.

Fertility medicine is moving toward intervention before failure — and that shift has implications beyond conception

Every insight Crawford shares points toward the same structural change: reproductive health should be proactive, not reactive. The AMH test, ovulation tracking, pre-conception toxin reduction, partner cannabis elimination — none of these require a diagnosis. They require only information given early enough to act on it.

The emerging GLP-1 data suggests that unexplained infertility may increasingly be understood as untreated inflammation — which means reproductive medicine is converging with metabolic medicine in ways that benefit women far beyond conception windows.

The single most reframing takeaway: fertility status is a leading indicator of systemic health, not just a reproductive metric. Know your AMH. Track when you ovulate, not just when you bleed. The biology doesn't wait for you to fail first.

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Topics: fertility, female reproductive health, egg quality, AMH testing, ovarian reserve, IVF, egg freezing, hormones, endometriosis, PCOS, cannabis and fertility, NSAIDs and ovulation, melatonin, CoQ10, GLP-1, inflammation, menopause, hormone replacement therapy, birth control, ovulation tracking