Hypothyroidism is common in women trying to conceive, and many take levothyroxine (Synthroid, Euthyrox and generics) every morning. Add a prenatal and a fertility formula, and the question becomes practical: can you take them together, and when? Here’s a simple timing plan to review with your doctor or pharmacist.
This is educational, not medical advice. For the bigger picture, see our guide to fertility supplements to get pregnant.
1. Why timing matters with thyroid medication
Levothyroxine is absorbed best on an empty stomach, and some common supplement ingredients — especially calcium and iron, both found in most prenatals — can reduce how much is absorbed if taken too close together. The prescribing information advises separating levothyroxine from calcium and iron products by at least 4 hours. Your pharmacist can confirm the right gap for your exact medicines.
2. A sample daily schedule
| Time | What | Why |
|---|---|---|
| On waking | Thyroid medication with water | Empty stomach, consistent time |
| Breakfast (30–60 min later) | Food and coffee | Follow your doctor’s wait time |
| Lunch or dinner | Prenatal (iron + calcium) and fertility formula | At least 4 hours after thyroid medication |
The key is consistency: same routine every day so your thyroid levels stay predictable. More on food, time of day and missed doses in how to take fertility supplements.
3. Tell your doctor about biotin before thyroid labs
Biotin, often found in hair-skin-nail and some multivitamin products, can interfere with certain lab tests, including thyroid tests, and the FDA has warned about this. If you take anything with biotin, tell your doctor before blood work — they may ask you to pause it beforehand. Don’t stack multiple products without checking: see what’s redundant in a TTC stack.
4. Where an AGO formula fits
Thyroid care stays with your doctor. Alongside it, many women choose one TTC formula to support overall reproductive wellness:
| Your situation | Often considered |
|---|---|
| Hypothyroid, TTC, regular cycles | AGO Mom + prenatal |
| Hypothyroid + irregular cycles | AGO Mom + AGO Eva |
| Hypothyroid + PCOS | See PCOS + hypothyroidism combo |
| Partner’s side | AGO Dad |
Bring the AGO label to your appointment so your doctor can review it with your medication list. More background: hypothyroidism and TTC and thyroid health and conception.
5. When you get a positive test
Call your doctor promptly: thyroid medication doses are often adjusted in pregnancy, and they’ll guide which supplements to keep. Our guide on what to do with fertility supplements after a positive test covers the rest. Results vary and no supplement guarantees pregnancy. Get a free personalized plan.
FAQ
Can I take fertility supplements with levothyroxine?
Many women do, with spacing. Calcium and iron, common in prenatals, can reduce levothyroxine absorption, so the prescribing information advises separating them by at least 4 hours. Confirm the timing with your pharmacist.
What time should I take my prenatal if I take thyroid medication in the morning?
Many people take thyroid medication on waking and move the prenatal and fertility formula to lunch or dinner, at least 4 hours later. Keep the same routine daily.
Does biotin affect thyroid tests?
Biotin can interfere with some lab tests, including thyroid tests. Tell your doctor about any biotin product before blood work.
Is AGO Mom safe with thyroid medication?
AGO Mom is a dietary supplement designed to support reproductive wellness. Bring the label to your doctor or pharmacist so they can check it against your medication list and timing.
Should I stop fertility supplements when I get pregnant?
Call your doctor promptly. Thyroid doses are often adjusted in pregnancy, and your doctor will tell you which supplements to continue.
Do you ship to the US and Canada?
Yes. AGO ships to the US and Canada; the care team can confirm delivery times for your area.