Written by Dr. Phoebe Howells, OVUM’s Co-Chief Medical Officer. Dr. Phoebe has been a doctor since 2012 with a decade of experience in Obstetrics and Gynaecology focusing on fertility. She's undertaken a clinical fellowship in Reproductive Medicine at a top London fertility clinic alongside authoring articles, sharing insights at global conferences, contributing to fertility trials for women with adenomyosis and working as the Co-Chief Medical Officer for OVUM.

Deciding to start or grow your family is a significant step, and it’s only natural to want to do everything you can to prepare. A healthy pregnancy begins with understanding your overall health and the medications you take. And it’s one of the most frequent questions in our inbox here at OVUM.

Medications work by interacting with the body at a cellular level, influencing various functions like nerve signalling or hormone production. While some medicines are known to impact fertility, others remain less understood. Learning about the medications you’re taking is a crucial part of preconception planning, as it helps you make informed choices that could reduce potential barriers to conceiving.

Why Medication Management Matters When Trying to Conceive

Infertility is more common than many people realise. In the UK, around 1 in 7 couples struggle to conceive, and globally, it’s 1 in 6, with factors such as age, health, lifestyle, and environment playing significant roles.

Medications are one factor that you can address proactively. Some drugs can disrupt ovulation or alter cervical mucus, making it harder for sperm to fertilise the egg or for the fertilised egg to implant in the uterus. Understanding how your medications work and discussing them with your healthcare provider can help you explore safer alternatives or adjustments.

Medications That May Affect Fertility

Non-Steroidal Anti-Inflammatory Drugs (NSAIDs)

NSAIDs are commonly used for pain relief, but certain types may affect fertility:

• Over-the-counter options like Naproxen and Diclofenac can interfere with ovulation and implantation.

• Prescription NSAIDs like Meloxicam, Rofecoxib, and Celecoxib may temporarily halt ovulation or reduce sperm count and motility.

Note: Ibuprofen is a non-selective COX inhibitor (drugs that inhibit the action of cyclooxygenase (COX) enzymes, which are key players in the production of prostaglandins) and is less likely to affect fertility in the same way as selective COX-2 inhibitor (which don’t block COX-1 enzymes meaning the body’s bloody clotting abilities are not impacted the same way as common NSAIDs like Ibuprofen).

Always consult your healthcare provider before taking NSAIDs when trying to conceive.

Anti-Seizure Medications

Some anti-seizure drugs can disrupt reproductive hormone levels, potentially reducing fertility. Common examples include:

• Phenobarbital

• Phenytoin

• Carbamazepine; and

• Valproic acid

Sodium valproate, in particular, has been linked to temporary male infertility. Work closely with your healthcare provider to explore safer options if you’re planning to conceive.

Antidepressants

Selective serotonin reuptake inhibitors (SSRIs) are a common type of antidepressant that can affect ovulation by raising prolactin levels. Examples include:

• Fluoxetine (brand name is ‘Prozac’)

• Sertraline (brand name is ‘Zoloft’)

SSRIs can also impact sperm count, motility, and DNA quality. However, it’s important not to stop antidepressants without medical guidance, as withdrawal symptoms and worsening mental health can have profound effects.

Mental well-being is vital to fertility, so speak to your doctor about adjusting medications safely.

Anti-Hypertensive Medications

Certain blood pressure medications, like beta blockers, may reduce blood flow to the uterus or interfere with implantation. Others, such as calcium channel blockers like Amlodipine, can affect sperm function.

If you’re taking medication for high blood pressure, discuss a personalised treatment plan with your healthcare provider before trying to conceive.

Diabetes Medications

Managing diabetes is crucial when planning a pregnancy. While many diabetes medications support overall health and fertility, some, like GLP-1 receptor agonists (e.g., Ozempic and Saxenda), are not recommended for use when trying to conceive or during pregnancy.

These medications should be stopped at least one to three months before trying to conceive, as they can affect blood sugar levels and reduce the effectiveness of some contraceptives. Speak to your healthcare provider for tailored advice.

Steroids

Corticosteroids, such as Prednisolone, may prevent a fertilised egg from implanting in the uterus. However, they are sometimes prescribed by fertility specialists to support pregnancy outcomes.

Discuss any steroid use with your doctor to understand the potential risks and benefits.

Natural Supplements

St. John’s Wort may interact with medications, and there is a lack of  evidence to confirm its safety during conception. When considering supplements, opt for those backed by science, and always consult a healthcare professional for personalised recommendations.

Supplements, Contraindications & Maximum Daily Doses

Supplements are significant in supporting fertility, addressing nutrient deficiencies, and improving overall health. However, it's essential to be aware of potential contraindications aka situations where supplements may interfere with certain medications or health conditions. Below are some key considerations:

Folic acid is crucial for women trying to conceive as it helps prevent neural tube defects. However, it may interact with certain medications. For example, folic acid can reduce the efficacy of anticonvulsants like Phenytoin and Valproic Acid. High doses of folic acid may also mask Vitamin B12 deficiency symptoms. When taking a fertility supplement, make sure it has both folate and B12. 

Vitamin D supports calcium absorption and is essential for immune function and reproductive health. However, excessive doses of Vitamin D can lead to hypercalcemia (high levels of calcium in the blood), which may cause kidney damage and interfere with certain medications such as corticosteroids and weight loss drugs. Sticking to the maximum recommended daily dose of 100mcg (4,000 IU) of Vitamin D is important.   

CoQ10 is used to support egg health and energy production. However, CoQ10 may interact with blood-thinning medications like Warfarin, increasing the risk of bleeding.

Zinc supports fertility by aiding cell division and hormone production. However, high levels of Zinc supplementation may interfere with the absorption of Copper, leading to deficiency. Additionally, Zinc may interact with certain antibiotics, such as Tetracyclines and Quinolones, reducing their effectiveness. 

Questions to Ask Your Healthcare Provider

Be proactive during preconception consultations by asking:

• Could any of my medications impact my fertility?

• Are there safer alternatives?

• What supplements should I take or avoid?

• How should I adjust my medications when I become pregnant?

Key Takeaways on Medications whilst TTC

Supplements can be valuable tools for supporting fertility, but it’s crucial to understand their role and potential contraindications [and ensure you are not accidentally overdosing on nutrients]. By understanding both the benefits and risks of medications and supplements, individuals can make informed decisions that support their fertility journey safely and effectively.